Method for CSI measurement and reporting in layer 1 and / or layer 2 triggered mobility

Abstract

In accordance with example embodiments of the invention there is at least a method and apparatus to perform communicating communications between a source candidate cell, and a target candidate cell of a communication network, comprising a transmission configuration activation command for a target candidate cell, wherein the transmission configuration activation command for the target candidate cell is for performing, based on completion of at least one condition, channel state information measurements for a triggered mobility operation for user equipment from the source cell to the target candidate cell; based on a channel state information acquisition configuration communicating in the communications from the source cell, performing at least one channel state information measurement acquisition on the target candidate cell; and reporting to the target candidate cell, information comprising measurements of channel state information resources on the target candidate cell for performing the triggered mobility operation.

Description

METHOD FOR CSI MEASUREMENT AND REPORTING IN LAYER 1 AND / ORLAYER 2 TRIGGERED MOBILITYTECHNICAL FIELD:

[0001] The teachings in accordance with the exemplary embodiments of this invention relate generally to a new method and apparatus for reducing the delay for the target cell to obtain the CSI measurements, and, more specifically, relate to a new method and apparatus for reducing the delay for the target cell to obtain the CSI measurements including for a Radio Resource Measurement (RRM) decision such as scheduling.BACKGROUND:

[0002] This section is intended to provide a background or context to the invention that is recited in the claims. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived or pursued. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.

[0003] Certain abbreviations that may be found in the description and / or in the Figures are herewith defined as follows:BWP Bandwidth PartCQI Channel Quality IndicatorCSI Chanel State InformationCSLRS Channel State Information Reference SignalCU Centralized UnitCG Configured GrantDCI Downlink Control IndicationDG Dynamic GrantDU Distributed UnitLI Layer 1L2 Layer 2LTM Ll / 2-triggered Mobility or Lower Layer Triggered MobilityRI Rank IndicatorRRM Radio Resource ManagementRS Reference SignalRSRP Reference Signal Received PowerPMI Precoding Matrix IndicatorPDCCH Physical Downlink Control ChannelPDSCH Physical Downlink Shared ChannelPUCCH Physical Uplink Control ChannelPUSCH Physical Uplink Shared ChannelQCL Quasi Co-locationSINR Signal to Interference and Noise RatioSSB Synchronization Block

[0004] LTM is a cell switch procedure, where UE’s serving cell (PCell or PSCell) is switched by the network by sending an LTM cell switch command. An LTM switch command is currently assumed delivered by MAC signaling using a MAC CE. Hence, not using RRC signaling as a L3 based handover which is one of the current methods for changing between cells. LTM cell switch decision is based on LI measurements that are performed and reported using LI measurement reports by the UE. Measurements and reporting are based on 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 UE’s current serving cells (e.g. SCells).

[0005] In Release-18, LTM measurements on a neighboring candidate cell are performed using SSBs transmitted by the candidate cell for which the SSB configuration is provided to the UE.

[0006] Example embodiments of the invention work to improve at least these operations.SUMMARY:

[0007] This section contains examples of possible implementations and is not meant to be limiting.

[0008] In another example aspect of the invention, there is an apparatus, such as a network side apparatus, comprising: at least one processor; and at least one non-transitory memory storing instructions, that when executed by the at least one processor, cause the apparatus at least to: receive communications from a source cell of a communication network, comprising a transmission configuration activation command for a target candidate cell, wherein the transmission configuration activation command for the target candidate cell is for performing, based on completion of at least one condition, channel state information measurements for a triggered mobility operation for user equipment from the source cell to the target candidate cell; based on a channel state information acquisition configuration received in the communications from the source cell, perform at least one channel state information measurement acquisition on the target candidate cell; and report to the target candidate cell, information comprising measurements of channel state information resources on the target candidate cell for performing the triggered mobility operation.

[0009] In still another example aspect of the invention, there is a method, comprising: receiving communications from a source cell of a communication network, comprising a transmission configuration activation command for a target candidate cell, wherein the transmission configuration activation command for the target candidate cell is for performing, based on completion of at least one condition, channel state information measurements for a triggered mobility operation for user equipment from the source cell to the target candidate cell; based on a channel state information acquisition configuration received in the communications from the source cell, performing at least one channel state information measurement acquisition on the target candidate cell; and report to the target candidate cell, information comprising measurements of channel state information resources on the target candidate cell for performing the triggered mobility operation.

[0010] A further example embodiment is an apparatus and a method comprising the apparatus and the method of the previous paragraphs, wherein the transmission configurationactivation command is received at least one of: prior to the cell switch command that switches the UE to the target candidate cell; or the transmission configuration activation command is received in the cell switch command, the transmission configuration activation command indicating a target transmission configuration indicator state for the target candidate cell.

[0011] A further example embodiment wherein the triggered mobility operation is a lower layer triggered mobility operation that is triggered after the receiving downlink control information from the target candidate cell, and wherein the reporting is performed one of upon or after the cell switch to the target candidate cell, wherein the at least one condition is based on at least one of: the at least one transmission configuration indicator state for the target cell is activated after receiving a physical downlink control channel ordered random access, or a physical downlink control channel ordered random access for the target candidate cell, or a physical downlink control channel ordered random access for the target candidate cell for which the transmission configuration activation command has activated at least one transmission configuration indicator state for the target candidate cell, or the at least one transmission configuration indicator state for the target cell is indicated in the cell switch command, or the at least on transmission configuration activation command has activated at least one transmission configuration indicator state for the target candidate cell

[0012] A further example embodiment wherein the transmission configuration activation command is received at least one of: prior to the cell switch command that switches the UE to the target candidate cell; or the transmission configuration activation command is received in the cell switch command, the transmission configuration activation command indicating a target transmission configuration indicator state for the target candidate cell.

[0013] A further example embodiment the transmission configuration indicator state comprises at least one of quasi co-location source for at least one channel state information reference signal associated with a synchronization signal block or a channel state information reference signal used for a timing advance acquisition, wherein there is selecting one of quasi co-location source reference signal for the at least one channel state referencesignal, or channel state information reference signals for performing the at least one channel state information measurement acquisition.

[0014] In a further example embodiment the quasi co-location source for the at least one channel state information reference signal is determined based on at least one of: at least one reference signal included in the activated transmission configuration indicator state for the target candidate cell, at least one reference signal included in the indicated transmission configuration indicator state in the cell switch command for the target candidate cell is, a target at least one reference signal of the physical downlink control channel order for the target candidate cell, a target at least one reference signal of the physical downlink control channel order for the target candidate cell for which the transmission configuration activation command has activated at least one transmission configuration indicator state for the target candidate cell.

[0015] In a further example embodiment the reporting the information comprising measurements of channel state information resources on the target candidate cell is sent with a channel state information acquisition flag to the target candidate cell, wherein there is receiving from the target candidate cell a physical downlink control channel downlink configuration indicator indicating channel state information acquisition and an uplink grant.

[0016] In a further example embodiment reporting the information comprising measurements of channel state information resources on the target candidate cell is using the uplink grant.

[0017] A further example embodiment there is determining at least one of the channel state information resource or a quasi co-location source reference signal used for performing the at least one channel state information measurement acquisition comprising at least one of: the channel state information resources in the target candidate cell or channel state resources listed in a target candidate cell configuration associated with the target candidate cell, the channel state information resources in the target candidate cell associated with an activated transmission configuration indicator state for the triggered lower layer mobility operation, the channel state information resources in the target candidate cell associated with the triggered lower layer mobility operation and for which an activatedtransmission configuration state provides a quasi co-location source reference signal, the channel state information resources in the target candidate cell for which at least one transmission configuration indicator state contains at least one of quasi co-location source reference signals associated with a synchronization signal block or a channel state information reference signal indicated in the physical downlink control channel order, or the channel state information resources in the target candidate cell for which at least one transmission configuration indicator state contains at least one of quasi co-location source reference signals associated with a synchronization signal block or a channel state information reference signal used for a timing advance acquisition.

[0018] In a further example embodiment the quasi co-location source may be the reference signal included in the indicated transmission configuration indicator, wherein the activated transmission configuration indicator state provides a quasi co-location source reference signal that the activated transmission configuration indicator transmission configuration indicator state to provide quasi co-location source reference signal for the measurement resource for channel state indicator acquisition. In a further example embodiment the reporting to the target candidate cell for the triggered lower layer mobility operation is performed based on at least one of upon or after the triggered lower layer mobility operation to the target candidate cell, upon request by the target candidate cell after the triggered mobility operation to the target candidate cell, if downlink control information based on scheduling a dynamic grant by the target cell indicates a channel state information request, if the first downlink control information by the target cell after a first uplink transmission indicates at least one channel state information acquisition request, if the downlink control information acknowledging a provisioned first uplink message requests at least one channel state information acquisition, if downlink control information indicates a at least one channel state information acquisition request within the X milliseconds after a triggered lower layer mobility operation to the target candidate cell, If downlink control information indicates certain codepoint in a field associated with a channel state information acquisition, or If the downlink control information indicates a channel state information report request with no linked measurement resource, if the downlink control information indicates a channel state information report request.

[0019] In a further example embodiment, sending the information comprising measurements of channel state information resources on the target candidate cell at least one of: on uplink resources indicated by a configured grant, on a dynamically scheduled uplink resource, or in a radio resource control reconfiguration complete message.

[0020] In a further example embodiment sending the information comprising measurements of channel state information resources on the target candidate cell based on a periodic channel state information reporting configuration to the target candidate cell, to provide obtained channel state information measurements in a first periodic reporting occasion or until channel state information is acquired in the target candidate cell according to the periodic channel state information reporting configuration,

[0021] In a further example embodiment sending the information comprising measurements of channel state information resources on the target candidate cell based on a latest at least one channel state measurement performed before or upon the triggered mobility operation for user equipment from the source cell to the target candidate cell.

[0022] In a further example embodiment sending the information comprising measurements of channel state information resources on the target candidate cell based on the latest channel state measurements performed before or upon the triggered mobility operation for user equipment from the source cell to the target candidate cell,

[0023] In a further example embodiment there is an indicating in a radio resource control reconfiguration complete message or message 3 of the random access procedure that channel state information is acquired for the target candidate cell,

[0024] In a further example embodiment the channel state information acquisition configuration received in the communications from the source cell comprises channel state information quantities based on at least one of: a channel quality indicator, a precoding matrix indicator, a channel state information reference signal resource indicator, a synchronization signal block or a channel state information reference signal, a layer indicator, a rank indicator, or a capability index or time-domain channel properties.

[0025] A non-transitory computer-readable medium storing program code, the program code executed by at least one processor to perform at least the method as described in the paragraphs above.

[0026] In yet another example aspect of the invention, there is an apparatus comprising: means for receiving communications from a source cell of a communication network, comprising a transmission configuration activation command for a target candidate cell, wherein the transmission configuration activation command for the target candidate cell is for performing, based on completion of at least one condition, channel state information measurements for a triggered mobility operation for user equipment from the source cell to the target candidate cell; means, based on a channel state information acquisition configuration received in the communications from the source cell, for performing at least one channel state information measurement acquisition on the target candidate cell; and means for reporting to the target candidate cell, information comprising measurements of channel state information resources on the target candidate cell for performing the triggered mobility operation.

[0027] In accordance with the example embodiments as described in the paragraph above, at least the means for receiving, performing, and / or reporting comprises a network interface, and computer program code stored on a computer-readable medium and executed by at least one processor.

[0028] In another example aspect of the invention, there is an apparatus, such as a user equipment side apparatus, comprising: at least one processor; and at least one non- transitory memory storing instructions, that when executed by the at least one processor, cause the apparatus at least to: communicate with a user equipment of a communication network based on a channel state information acquisition configuration, information for performing a triggered lower layer mobility operation for a cell switch of the user equipment from a source cell to the target candidate cell; and communicate with the user equipment a transmission configuration activation command for performing, based on completion of at least one condition, channel state information measurements for the triggered lower layer mobility operation for the user equipment from the source cell to the target candidate cell,wherein the channel state information reporting is communicated one of upon or after the cell switch to the target candidate cell.

[0029] In still another example aspect of the invention, there is a method, comprising: communicating with a user equipment of a communication network based on a channel state information acquisition configuration, information for performing a triggered lower layer mobility operation for a cell switch of the user equipment from a source cell to the target candidate cell; and communicating with the user equipment a transmission configuration activation command for performing, based on completion of at least one condition, channel state information measurements for the triggered lower layer mobility operation for the user equipment from the source cell to the target candidate cell, wherein the channel state information reporting is communicated one of upon or after the cell switch to the target candidate cell.

[0030] A further example embodiment is an apparatus and a method comprising the apparatus and the method of the previous paragraphs, wherein the at least one condition is based on at least one of: the at least one transmission configuration indicator state for the target candidate cell is activated, or a physical downlink control channel order for the target candidate cell for which the transmission configuration indicator state activation command has activated at least one transmission configuration indicator state for the target candidate cell, or the at least one transmission configuration indicator state for the target cell is indicated in the cell switch command.

[0031] In a further example embodiment wherein the communicating comprises at least one of a configuration activation or indication command for the target candidate cell, and wherein the transmission configuration activation command for a target candidate cell is for performing, based on completion of at least one condition, channel state information measurements for a triggered mobility operation for user equipment from the source cell to a target candidate cell.

[0032] In a further example embodiment wherein the triggered lower layer mobility operation is a lower layer triggered mobility operation that is triggered after downlink control information from the target candidate cell is sent, and wherein the reporting is configured to be performed upon or after the cell switch to the target candidate cell, wherein reporting theinformation comprising measurements of channel state information resources on the target candidate cell is using an uplink grant, wherein the information comprising measurements of channel state information resources further comprises a channel state information acquisition flag to the target candidate cell for performing the triggered mobility operation.

[0033] In a further example embodiment wherein the perform at least one channel state information measurement acquisition on a target candidate cell is performed at least one of: upon or after the triggered mobility operation to the target candidate cell, upon request by the target candidate cell after the triggered mobility operation to the target candidate cell, if downlink control information based on scheduling a dynamic grant that indicates a channel state information request, if the first downlink control information after a first uplink transmission indicates at least one channel state information acquisition request, if the downlink control information acknowledging a provisioned first uplink message requests at least one channel state information acquisition, if downlink control information indicates a at least one channel state information acquisition request within the X milliseconds after triggered mobility operation to the target candidate cell, if downlink control information indicates certain codepoint in a field associated with a channel state information acquisition, or if the downlink control information indicates a channel state information report request with no linked measurement resource, wherein there is receiving information comprising measurements of channel state information resources on the target candidate cell at least one of: on uplink resources indicated by a configured grant, on a dynamically scheduled uplink resource, or in a radio resource control reconfiguration complete message, or in a message 3 of the random access procedure.

[0034] In a further example embodiment wherein there is receiving information comprising measurements of channel state information resources on the target candidate cell based on a periodic channel state information reporting configuration to the target candidate cell, to provide obtained channel state information measurements in a first periodic reporting occasion or until channel state information is acquired in the target candidate cell according to the periodic channel state information reporting configuration, wherein there is receiving in a radio resource control reconfiguration at least one of a complete message or message 3 that channel state information for the target candidate cell, wherein the channel state information acquisition configuration comprises channel state information quantities basedon at least one of: a channel quality indicator, a precoding matrix indicator, a channel state information reference signal resource indicator, a synchronization signal block or a channel state information reference signal, a layer indicator, a rank indicator, or a capability index or time-domain channel properties.

[0035] In yet another example aspect of the invention, there is an apparatus comprising: means for communicating with a user equipment of a communication network based on a channel state information acquisition configuration, information for performing a triggered lower layer mobility operation for a cell switch of the user equipment from a source cell to the target candidate cell; and means for communicating with the user equipment a transmission configuration activation command for performing, based on completion of at least one condition, channel state information measurements for the triggered lower layer mobility operation for the user equipment from the source cell to the target candidate cell, wherein the channel state information reporting is communicated one of upon or after the cell switch to the target candidate cell.

[0036] In accordance with the example embodiments as described in the paragraph above, at least the means for communicating comprises a network interface, and computer program code stored on a computer-readable medium and executed by at least one processor.

[0037] A communication system comprising the network side apparatus and the user equipment side apparatus performing operations as described above.BRIEF DESCRIPTION OF THE DRAWINGS:

[0038] The above and other aspects, features, and benefits of various embodiments of the present disclosure will become more fully apparent from the following detailed description with reference to the accompanying drawings, in which like reference signs are used to designate like or equivalent elements. The drawings are illustrated for facilitating better understanding of the embodiments of the disclosure and are not necessarily drawn to scale, in which:

[0039] FIG. 1 shows a signaling diagram of an LTM procedure based on TS 38.300 V18.0.0;

[0040] FIG. 2 shows main components of Rel-18 LTM configuration and how they are placed;

[0041] FIG. 3 shows a high level view of LTM configuration given in RRC;

[0042] FIG. 4 shows an LTM-CSI-ReportConfig information element;

[0043] FIG. 5 shows LTM-CSI-ReportConfig field descriptions;

[0044] FIG. 6 shows LTM-ReportContent field descriptions;

[0045] FIG. 7 shows an LTM-CSI-ReportConfigld information element;

[0046] FIG. 8 shows an LTM-CSI-ResourceConfig information element;

[0047] FIG. 9 shows LTM-CSI-ResourceConfig field descriptions;

[0048] FIG. 10 shows LTM-CSLSSB-ResourceSet field descriptions;

[0049] FIG. 11 shows a 3GPP TS 38.331 TCI state;

[0050] FIG. 12 shows NZP-CSI-RS-Resource information element;

[0051] FIG. 13 shows an SSB 1 serving as source RS for QCL information of CSL RS 1;

[0052] FIG. 14 shows An example showing some proposed options for Candidate Cell CSI acquisition;

[0053] FIG. 15 shows a high level block diagram of various devices used in carrying out various aspects of the invention; and

[0054] FIG. 16A and FIG. 16B each show a method in accordance with example embodiments of the invention which may be performed by an apparatus.DETAILED DESCRIPTION:

[0055] In example embodiments of this invention there is proposed at least a method and apparatus for a method and apparatus for reducing the delay for the target cell to obtain the CSI measurements, or more specifically for reducing the delay for the target cell to obtain the CSI measurements including for a Radio Resource Measurement (RRM) decision such as scheduling.

[0056] As similarly stated above, LTM is a cell switch procedure, where UE’s serving cell (PCell or PSCell) is switched by the network by sending an LTM cell switch command. An LTM switch command is currently assumed delivered by MAC signaling using a MAC CE. Hence, not using RRC signaling as a L3 based handover which is one of the current methods for changing between cells. LTM cell switch decision is based on LI measurements that are performed and reported using LI measurement reports by the UE. Measurements and reporting are based on 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 UE’s current serving cells (e.g. SCells).

[0057] In Release-18, LTM measurements on a neighboring candidate cell are performed using SSBs transmitted by the candidate cell for which the SSB configuration is provided to the UE.

[0058] Before the cell switch, network may optionally activate one or more TCI state(s) for one or more candidate cells. Once a candidate cell TCI state is activated the UE may start tracking the 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.

[0059] FIG. 1 shows a signaling diagram of an LTM procedure based on TS 38.300 V18.0.0.

[0060] A procedure for LTM is as follows:1. The UE sends a MeasurementReport message to the gNB. The gNB decides to configure LTM and initiates LTM preparation;2. The gNB transmits an RRCReconfiguration message to the UE including the LTM candidate configurations;3. The UE stores the LTM candidate configurations and transmits an RRCReconfigurationComplete message to the gNB;4a. The UE performs DL synchronization with the candidate cell(s) before receiving the cell switch command;4b. UE performs early TA acquisition with the candidate cell(s) as requested by the network before receiving the cell switch command as specified in clause 9.2.6 [38.300], This is done via CFRA triggered by a PDCCH order from the source cell, following which the UE sends preamble towards the indicated candidate cell. In order to minimize the data interruption of the source cell due to CFRA towards the candidate cell(s), the UE doesn’t 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 doesn’t maintain the TA timer for the candidate cell and relies on network implementation to guarantee the TA validity;5. The UE performs LI measurements on the configured candidate cell(s) and transmits LI measurement reports to the gNB. LI measurement should be performed as long as RRC reconfiguration (step 2) is applicable;6. The gNB decides to execute cell switch to a target cell and transmits a MAC CE triggering cell switch by including the candidate configuration index of the target cell. The UE switches to the target cell and applies the configuration indicated by candidate configuration index;7. The UE performs the random access procedure towards the target cell, if UE does not have valid TA of the target cell as specified in clause 6.1.3.75 of TS 38.321;8. The UE completes the LTM cell switch procedure by sending RRCReconfigurationComplete message to target cell. If the UE has performed a RA procedure in step 7 the UE considers that LTM cell switch execution is successfully completed when the random access procedure is successfully completed. For RACH- less LTM, the UE considers that LTM cell switch execution is successfully completed when the UE determines that the network has successfully received its first UL data.

[0061] The steps 4-8 can be performed multiple times for subsequent LTM using the LTM candidate configuration(s) provided in step 2.

[0062] The procedure over the air interface described above is applicable to both intra-gNB-DU LTM and inter-gNB-DU LTM. The overall LTM procedures over Fl-C interface are captured in TS 38.401.

[0063] LI Measurement Configuration in Release- 18 LTM

[0064] In Release-18 LTM, information about measurement resources (SSBs)from LTM candidate cells are provided to the UE so that UE can make measurements. The UE is also configured with LI measurement reporting configuration where the UE can report the measurements. For LTM, periodic and semi-persistent reports on PUCCH, semi-persistent report on PUSCH, and aperiodic report on PUSCH are supported.

[0065] The UE can be configured with one or more LTM CSI reporting configurations (LTM-CSI-ReportConfig) where each reporting configuration contains a LTM CSI resource configuration (LTM-CSI-ResourceConfig) containing the information of resources to be used for channel measurements (Ll-RSRP measurements). 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) contains configuration of an LTM-CSI-SSB-ResourceSet which comprises of a list of Z > 1 SS / PBCH blocks indices (given by Itm-CSI-SSB-ResourceLisf) and a list ofZ LTM-Candidatelds (given by Itm-CandidatelDLisf) referring to candidate cells associated with the SS / PBCH block indices.

[0066] FIG. 2 shows main components of Rel-18 LTM configuration and how they are placed;

[0067] FIG. 2 shows a “LTM-CSI-ReportConfig #n, an LTM-CSI-ReportConfig #m, a LTM-CSI-SSB-ReportSet. These are going to an Itm-CSI-SSB-ResourceList and Itm- CSI-SSB-CandidatelDList as shown in FIG. 2. The Itm-CSI-SSB-ResourceList includes SSB kl-k2-k3-kn, and the Itm-CSI-SSB-CandidatelDList of FIG. 2 includes a Candidate ID #rl-r2-r3-rn.

[0068] For each candidate cell, the UE determines the time domain behavior of a SS / PBCH block resource from ssb-Periodicity and ssb-PositionsInBurst and the frequency domain behavior of a SS / PBCH block resource is determined by the higher layer parameters subCarrier Spacing, ssbFrequency.

[0069] For each cell, LTM CSI Report Configurations are given under current serving cell’ s configuration where each report configuration contains an indication of a LTM CSI Resource Config and other parameters related for reporting, e.g., timing and uplink resources to transmit reports.

[0070] 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.

[0071] The detailed configuration of each SSB of a candidate cell indicated in a LTM CSI Resource 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.

[0072] The LTM-Candidate IE also contains the list of NZP-CSLRS resources which are currently used to provide the information for activation of TCI states associated with tracking RS (a type of CSLRS). The same may be used for LTM measurements with CSI-RSs.

[0073] An LTM-Candidate IE also includes 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.

[0074] FIG. 2 shows the main components of Rel-18 LTM configuration and how they are placed.

[0075] FIG. 3 shows a high level view of LTM configuration given in RRC.

[0076] FIG. 3 shows an LTM-Config with an LTM reference configuration going to3 cells, Cell 1, Cell 2, and Cell 3. Each of these cell of FIG. 3 include Serving Cell and Candidate Cells identifications.

[0077] Further information elements details of LTM-CSI-ReportConfig, LTM-CSL ResourceConfig, and LTM-CSI-SSB-ResourceSet are given below from 38.331.

[0078] LTM-CSI-ReportConfig

[0079] The IE LTM-CSI-ReportConfig is used to configure reports on the cell in which the LTM-CSI-ReportConfig is included.

[0080] FIG. 4 shows an LTM-CSI-ReportConfig information element.

[0081] LTM-CSI-ReportConfigld

[0082] The IE LTM-CSI-ReportConfigld is used to identify an LTM-CSL ReportConfig.

[0083] LTM-CSI-ResourceConfig

[0084] The IE LTM-CSI-ResourceConfig defines a group of one or more CSI resources for one or more LTM candidate configurations.

[0085] LTM-CSI-ResourceConfigld

[0086] The IE LTM-CSI-ResourceConfigld is used to identify an LTM-CSI- ResourceConfig.

[0087] FIG. 4 shows an LTM-CSI-ReportConfig information element.

[0088] FIG. 5 shows LTM-CSI-ReportConfig field descriptions.

[0089] FIG. 6 shows LTM-ReportContent field descriptions.

[0090] FIG. 7 shows an LTM-CSI-ReportConfigld information element.

[0091] FIG. 8 shows an LTM-CSI-ResourceConfig information element.

[0092] FIG. 9 shows LTM-CSI-ResourceConfig field descriptions.

[0093] FIG. 10 shows LTM-CSI-SSB-ResourceSet field descriptions.

[0094] Release 19 NR Mobility Enhancements

[0095] LTM was introduced in Rel-18 and can offer improvements in handover latency and interruption time compared to Layer 3 based mobility. However, LTM as introduced in Rel-18 also has a number of limitations compared to Layer 3 mobility. This Rel-19 work item aims to remove a number of these limitations with the following objectives. One of the objectives is to enable CSLRS measurements for LTM procedures.

[0096] The Rel-18 WID on “Further NR mobility enhancements” was agreed to specify mechanism and procedures of Layer 1 / Layer 2 (Ll / L2)-triggered mobility (LTM).

[0097] To maintain high data transmission efficiency and reliability in the process of fast cell switch, early CSI acquisition for the candidate cell(s) would be beneficial so that the UE would be able to use high data link with the target cell immediately after the cell switch.In example embodiments of this invention, a procedure is proposed to enable CSI acquisition for a candidate cell before the cell switch command is received by the UE in Rel-18 LTM. The ideas of the Invention will be presented at RANI #111 meeting.

[0098] Specify support for inter-CU Layer 2 Mobility (LTM) [RAN2, RAN3], for example: o Prioritize the case when CU is acting as MN when DC is not configured; o As secondary priority, support the case when NR-DC is configured and CU is acting as SN and MCG is unchanged; o As secondary priority, support the case when NR-DC is configured, CU is acting as MN and SCG is unchanged or SCG is released; o Note: The case that LTM is configured in both MCG and SCG is excluded; o Specify support for subsequent LTM mobility procedures aiming to avoid RRC configuration between cell switches as per Rel-18 LTM;■ Coordination with SA3 needed with respect to security key handling; o Note: Rel. 18 intra-CU LTM procedure is considered as baseline for adding inter- CU support• Measurements related enhancements for purpose of supporting LTM: [RAN2, RANI], for example: Measurement related enhancements are applicable to Intra-CU MCG / SCG LTM and Inter-CU MCG / SCG LTM; Specify necessary components to support event triggered LI measurement reporting [RAN2, RANI];■ RANI and RAN2 to progress independently on the event triggered measurements objectives of their respective MIMO and Mobility enhancement WIs. Review progress at RAN#105 to see if any modification of objectives is required to avoid / manage any overlap in the work; o Specify support for CSI-RS measurements for LTM procedures and enable CSI-RS based beam management, and / or other necessary physical layer operations on candidate cells before LTM [RANI];• Specify support of conditional LTM [RAN2, RAN3, RANI]; o Specify UE evaluated conditions for triggering LTM; o Aim to support conditional LTM including subsequent LTM; o Prioritize intra-CU LTM; o Checkpoint to review objective at RAN#105. RAN WG work to not start before this checkpoint;• Specify RRM requirements related to the above objectives as necessary [RAN4],

[0099] CSI-RS based measurements of neighboring candidate target cells will be used at least for cell switch decisions, target cell beam selection, and maybe for other physical layer procedures such as CSI acquisition with the target cell.

[0100] From CSI acquisition we mean, acquiring the channel parameters, such as Channel Quality Indicator (CQI), precoding matrix indicator (PMI), layer indicator (LI), rank indicator (RI), which are used to set the appropriate modulation & coding rate, appropriate MIMO configuration (e.g., number of layers, precoding matrix) of the channel.

[0101] Channel State Information (CSI) Framework (TS 38,214)

[0102] The detail of serving cell CSI acquisition is specified in section 5.2, TS 38.214.

[0103] CSI-RS configuration and OCL information

[0104] In order to trigger the cell change in step 6 of Fig. 1, the serving DU needs to indicate the Transmission Configuration Index (TCI) State which includes the QCL information for receiving on PDCCH / PDSCH from the target cell (DL reception) or / and for transmitting on PUCCH / PUSCH (UL transmission).

[0105] The QCL information contains 1) the Reference Signal (RS) and 2) QCL type = typeA, typeB, typeC and typeD 3) the bandwidth part (bwp) which the RS is located.

[0106] FIG. 11 shows for 3GPP TS 38.331 a 3GPP TS 38.331 TCI state.

[0107] The definitions of the QCL types are provided in TS 38.214:'typeA': {Doppler shift, Doppler spread, average delay, delay spread}'typeB': {Doppler shift, Doppler spread}'typeC: {Doppler shift, average delay}'typeD': {Spatial Rx parameter}

[0108] For switching the serving beam, one of the following options are allowed for QCL-info:(1) qcl-Typel : referencesignal = Tracking RS (TRS) index where TRS is a special configuration of CSLRS index (see below) and qcl-Type = A, qcl-Type2 (applicable only in FR2): referencesignal = same TRS index and qcl-Type = D;(2) qcl-Typel : referencesignal = Tracking RS (TRS) index and qcl-Type = A, qcl- Type2 (applicable only in FR2): referencesignal = CSLRS index with repetition and qcl-Type = D.

[0109] For instance, in option 1) and for FR1 the serving cell indicates to the TRS index as the QCL source which shall be used by the UE to estimate the channel properties (doppler shift, doppler spread, average delay, delay spread) for receiving PDCCH / PDSCH or / and transmitting PUCCH / PUSCH.

[0110] The configuration of a CSI-RS resource is shown in TS 38.331.

[0111] NZP-CSI-RS-Resource

[0112] The IE NZP-CSI-RS-Resource is used to configure Non-Zero-Power (NZP) CSI-RS transmitted in the cell where the IE is included, which the UE may be configured to measure on (see TS 38.214

[0019] , clause 5.2.2.3.1). A change of configuration between periodic, semi-persistent or aperiodic for an NZP-CSI-RS-Resource is not supported without a release and add.

[0113] FIG. 12 shows NZP-CSI-RS-Resource information element.

[0114] For a CSI-RS resource, there might be an SSB-index which serves as source RS for QCL information (given by the qcl-InfoPeriodicCSI-RS which points to a TCI state which further points to its QCL source RS). This can be done either direct or indirect QCL chain reference. In case of direct QCL reference, a SSB can be configured as the QCL source of the CSI-RS. In case of indirect QCL reference, for example, a CSI-RS can have another CSI-RS as the QCL reference where the reference CSI-RS has a SSB as its QCL reference. Given that an SSB is typically transmitted using a wider beam compared with a CSI-RS, multiple CSI-RS indices might be associated with the same source SSB-index. For instance, in the example found in FIG. 13. In FIG. 13 the SSB 1 serves as source RS for QCL information of CSI-RS 1, CSI-RS 2, CSI-RS 3 and CSI-RS 4 and SSB 2 for CSI-RS 5 to 8.

[0115] FIG. 13 shows an SSB 1 serving as source RS for QCL information of CSI- RS 1. FIG. 13 shows an SSB 1 and an SSB 2 communicating over one another CS-RS1-CS- RS8.

[0116] NC327234 - EARLY CHANNEL STATE INFORMATIONACQUISITION FOR TARGET CELL IN L1 / L2 INTER-CELL MOBILITY

[0117] In this invention a solution is considered where the UE is configured to measure CSI quantities such as RI, PMI, CQI with a candidate cell and report it to the serving cell. Serving cell then forwards it to the candidate cell.

[0118] Solutions for UE-based filtering of CSI measurements for reporting were considered where the UE only reports certain measurements, e.g., strongest cell quality, strongest N beams of a cell (based on Ll-RSRP). Alternative NW-based selection of candidate cells for forwarding CSI measurements to candidate cells based on cell quality or / and number of beams above threshold were considered.

[0119] However, the following aspects were not captured: o Early CSI acquisition (measurements are acquired prior to the cell switch) but reporting is performed to the target cell directly after cell switch; o UE performing CSI acquisition based on early DL and UL synch criterion.

[0120] One of the motivations of LTM is to maintain high data transmission efficiency and reliability in the process of fast cell switch, early CSI acquisition (parameters like CQI, RI, PMI, or / and LI) for the candidate cell(s) would be beneficial so that the UE would be able to use high data link (by setting appropriate higher modulation & coding, higher number of MIMO layers, etc.) with the target cell immediately after the cell switch.

[0121] To determine CSI of a candidate cell (i.e., a candidate cell for the target cell), how CSI-RSs of the candidate cell would be configured for the UE to make CSI measurements; how the CSI measurements would be reported to the candidate cell without incurring any significant interruption to the serving cell communication with the UE and without incurring any significant over the air and inter-cell / DU signaling overhead.

[0122] In other words, the problem that the invention aims to solve is how to reduce the delay for the target cell to obtain the CSI measurements that might be useful for Radio Resource Measurement (RRM) decision such as scheduling, etc. Currently, the UE starts toperform CSI measurements for the target cell after the cell change and the target cell will receive the first CSI measurements only after some time that is needed for the UE perform these measurements. During this time, the target cell will not be able to make optimal RRM decisions.

[0123] Before describing the example embodiments as disclosed herein in detail, reference is made to FIG. 15 for illustrating a simplified block diagram of various electronic devices that are suitable for use in practicing the example embodiments of this invention.

[0124] FIG. 15 shows a block diagram of one possible and non-limiting exemplary system in which the example embodiments may be practiced. In FIG. 15, a user equipment (UE) 10 is in wireless communication with a wireless network 1 or network, 1 as in FIG. 15. The wireless network 1 or network 1 as in FIG. 15 can comprise a communication network such as a mobile network e.g., the mobile network 1 or first mobile network as disclosed herein. Any reference herein to a wireless network 1 as in FIG. 15 can be seen as a reference to any wireless network as disclosed herein. Further, the wireless network 1 as in FIG. 15 can also comprises hardwired features as may be required by a communication network. A UE is a wireless, typically mobile device that can access a wireless network. The UE, for example, may be a mobile phone (or called a "cellular" phone) and / or a computer with a mobile terminal function. For example, the UE or mobile terminal may also be a portable, pocket, handheld, computer-embedded or vehicle-mounted mobile device and performs a language signaling and / or data exchange with the RAN.

[0125] The UE 10 includes one or more processors DP 10 A, one or more memories MEM 10B, and one or more transceivers TRANS 10D interconnected through one or more buses. Each of the one or more transceivers TRANS 10D includes a receiver and a transmitter. The one or more buses may be address, data, or control buses, and may include any interconnection mechanism, such as a series of lines on a motherboard or integrated circuit, fiber optics or other optical communication equipment, and the like. The one or more transceivers TRANS 10D which can be optionally connected to one or more antennas for communication to NN 12 and NN 13, respectively. The one or more memories MEM 10B include computer program code PROG 10C. The UE 10 communicates with NN 12 and / or NN 13 via a wireless link 11 or 16.

[0126] The NN 12 (NR / 5G / 6G Node B, an evolved NB, or LTE device) is a network node such as a master or secondary node base station (e.g., for NR or LTE long term evolution) that communicates with devices such as NN 13 and UE 10 of FIG. 15. The NN 12 provides access to wireless devices such as the UE 10 to the wireless network 1. The NN 12 includes one or more processors DP 12A, one or more memories MEM 12B, and one or more transceivers TRANS 12D interconnected through one or more buses. In accordance with the example embodiments these TRANS 12D can include X2 and / or Xn interfaces for use to perform the example embodiments. Each of the one or more transceivers TRANS 12D includes a receiver and a transmitter. The one or more transceivers TRANS 12D can be optionally connected to one or more antennas for communication over at least link 11 with the UE 10. The one or more memories MEM 12B and the computer program code PROG 12C are configured to cause, with the one or more processors DP 12 A, the NN 12 to perform one or more of the operations as described herein. The NN 12 may communicate with another gNB or eNB, or a device such as the NN 13 such as via link 16. Further, the link 11, link 16 and / or any other link may be wired or wireless or both and may implement, e.g., an X2 or Xn interface. Further the link 11 and / or link 16 may be through other network devices such as, but not limited to an NCE / MME / SGW / UDM / PCF / AMF / SMF / LMF 14 device as in FIG. 15. The NN 12 may perform functionalities of an MME (Mobility Management Entity) or SGW (Serving Gateway), such as a User Plane Functionality, and / or an Access Management functionality for LTE and similar functionality for 5G or 6G.

[0127] The NN 13 can be for WiFi or Bluetooth or other wireless device associated with a mobility function device such as an AMF or SMF, further the NN 13 may comprise a NR / 5G / 6G Node B or possibly an evolved NB a base station such as a master or secondary node base station (e.g., for NR or LTE long term evolution) that communicates with devices such as the NN 12 and / or UE 10 and / or the wireless network 1. The NN 13 includes one or more processors DP 13 A, one or more memories MEM 13B, one or more network interfaces, and one or more transceivers TRANS 13D interconnected through one or more buses. In accordance with the example embodiments these network interfaces of NN 13 can include X2 and / or Xn interfaces for use to perform the example embodiments. Each of the one or more transceivers TRANS 13D includes a receiver and a transmitter that can optionally be connected to one or more antennas. The one or more memories MEM 13B include computerprogram code PROG 13C. For instance, the one or more memories MEM 13B and the computer program code PROG 13C are configured to cause, with the one or more processors DP 13 A, the NN 13 to perform one or more of the operations as described herein. The NN 13 may communicate with another mobility function device and / or eNB such as the NN 12 and the UE 10 or any other device using, e.g., link 11 or link 16 or another link. The link 16 as shown in FIG. 15 can be used for communication with the NN12. These links maybe wired or wireless or both and may implement, e.g., an X2 or Xn interface. Further, as stated above the link 11 and / or link 16 may be through other network devices such as, but not limited to, an NCE / MME / SGW device such as the NCE / MME / SGW / UDM / PCF / AMF / SMF / LMF 14 of FIG. 15.

[0128] The one or more buses of the device of FIG. 15 may be address, data, or control buses, and may include any interconnection mechanism, such as a series of lines on a motherboard or integrated circuit, fiber optics or other optical communication equipment, wireless channels, and the like. For example, the one or more transceivers TRANS 12D, TRANS 13D and / or TRANS 10D may be implemented as a remote radio head (RRH), with the other elements of the NN 12 being physically in a different location from the RRH, and these devices can include one or more buses that could be implemented in part as fiber optic cable to connect the other elements of the NN 12 to a RRH.

[0129] It is noted that although FIG. 15 shows a network nodes such as NN 12 and NN 13, any of these nodes may be incorporate or be incorporated into an eNodeB or eNB or gNB such as for LTE and NR, and would still be configurable to perform example embodiments.

[0130] Also it is noted that description herein indicates that “cells” perform functions, but it should be clear that the gNB that forms the cell and / or a user equipment and / or mobility management function device that will perform the functions. In addition, the cell makes up part of a gNB, and there can be multiple cells per gNB.

[0131] The wireless network 1 or any network it can represent may or may not include a NCE / MME / SGW / UDM / PCF / AMF / SMF / LMF 14 that may include (NCE) network control element functionality, MME (Mobility Management Entity ) / SGW (ServingGateway) functionality, and / or serving gateway (SGW), and / or MME (Mobility Management Entity) and / or SGW (Serving Gateway) functionality, and / or user data management functionality (UDM), and / or PCF (Policy Control) functionality, and / or Access and Mobility Management Function (AMF) functionality, and / or Session Management (SMF) functionality, and / or Location Management Function (LMF), and / or Authentication Server (AUSF) functionality and which provides connectivity with a further network, such as a telephone network and / or a data communications network (e.g., the Internet), and which is configured to perform any 5G, 6G, and / or NR operations in addition to or instead of other standard operations at the time of this application. The NCE / MME / SGW / UDM / PCF / AMF / SMF / LMF 14 is configurable to perform operations in accordance with example embodiments in any of an LTE, NR, 5G, 6G, and / or any standards based communication technologies being performed or discussed at the time of this application. In addition, it is noted that the operations in accordance with example embodiments, as performed by the NN 12 and / or NN 13, may also be performed at the NCE / MME / SGW / UDM / PCF / AMF / SMF / LMF 14.

[0132] The NCE / MME / SGW / UDM / PCF / AMF / SMF / LMF 14 includes one or more processors DP 14A, one or more memories MEM 14B, and one or more network interfaces (N / W I / F(s)), interconnected through one or more buses coupled with the link 13 and / or link 16. In accordance with the example embodiments these network interfaces can include X2 and / or Xn interfaces for use to perform the example embodiments. The one or more memories MEM 14B include computer program code PROG 14C. The one or more memories MEM14B and the computer program code PROG 14C are configured to, with the one or more processors DP 14A, cause the NCE / MME / SGW / UDM / PCF / AMF / SMF / LMF 14 to perform one or more operations which may be needed to support the operations in accordance with the example embodiments.

[0133] It is noted that that the NN 12 and / or NN 13 and / or UE 10 can be configured (e.g. based on standards implementations etc.) to perform functionality of a Location Management Function (LMF). The LMF functionality may be embodied in any of these network devices or other devices associated with these devices. In addition, an LMF such as the LMF of the MME / SGW / UDM / PCF / AMF / SMF / LMF 14 of FIG. 15, as at least described below, can be co-located with UE 10 such as to be separate from the NN 12 and / or NN 13of FIG. 15 for performing operations in accordance with example embodiments as disclosed herein.

[0134] The wireless Network 1 may implement network virtualization, which is the process of combining hardware and software network resources and network functionality into a single, software-based administrative entity, a virtual network. Network virtualization involves platform virtualization, often combined with resource virtualization. Network virtualization is categorized as either external, combining many networks, or parts of networks, into a virtual unit, or internal, providing network-like functionality to software containers on a single system. Note that the virtualized entities that result from the network virtualization are still implemented, at some level, using hardware such as processors DP 10, DP12A, DP13A, and / or DP14A and memories MEM 10B, MEM 12B, MEM 13B, and / or MEM 14B, and also such virtualized entities create technical effects.

[0135] The computer readable memories MEM 12B, MEM 13B, and MEM 14B may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor based memory devices, flash memory, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. The computer readable memories MEM 12B, MEM 13B, and MEM 14B may be means for performing storage functions. The processors DP10, DP12A, DP13A, and DP14A may be of any type suitable to the local technical environment, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on a multi-core processor architecture, as non-limiting examples. The processors DP10, DP12A, DP13A, and DP14A may be means for performing functions, such as controlling the UE 10, NN 12, NN 13, and other functions as described herein.

[0136] In general, various embodiments of any of these devices can include, but are not limited to, cellular telephones such as smart phones, tablets, personal digital assistants (PDAs) having wireless communication capabilities, portable computers having wireless communication capabilities, image capture devices such as digital cameras having wireless communication capabilities, gaming devices having wireless communication capabilities, music storage and playback appliances having wireless communication capabilities, Internetappliances permitting wireless Internet access and browsing, tablets with wireless communication capabilities, as well as portable units or terminals that incorporate combinations of such functions.

[0137] Further, the various embodiments of any of these devices can be used with a UE vehicle, a High Altitude Platform Station, or any other such type node associated with a terrestrial network or any drone type radio or a radio in aircraft or other airborne vehicle or a vessel that travels on water such as a boat.

[0138] As similarly stated above, a problem that example embodiments of the invention aims to solve is how to reduce the delay for the target cell to obtain the CSI measurements that might be useful for Radio Resource Measurement (RRM) decision such as scheduling, etc.

[0139] According to the current description, the target cell / DU starts CSI measurements including higher layer parameters after the cell change. During the time the CSI measurements take place, the target cell is not be able to make optimal RRM decisions.

[0140] Therefore, one problem example embodiments of this invention aims to solve is how.

[0141] As indicated above, at the time of this application the UE starts to perform CSI measurements for the target cell after the cell change and the target cell will receive the first CSI measurements only after some time that is needed for the UE perform these measurements. During this time, the target cell will not be able to make optimal RRM decisions.

[0142] In this invention we propose method(s) for performing and reporting CSI measurements on LTM candidate as part of the LTM operation (e.g. cell switch procedure), where we consider: o configuration of CSI measurement resources and reporting configuration are associated with LTM cell switch operation;o etermines whether to perform CSI acqui sition for a LTM candidate cell based on certain conditions, i.e., based on the early DL / IJL synch status, cell switch triggering, etc.; o letermines CSI resource or resources for CSI acquisition based on certain QCL source TCI states (e.g., based on activated or indicated TCI state); o Reporting mechanism to report the CSI measurements to the target cell.

[0143] Example embodiments of the invention proposes to enable CSI acquisition for a candidate cell before the cell switch command is received by the UE.

[0144] There are included as main steps:1) Together with LI beam measurements for one or more candidate cells, the UE is configured with a CSI reporting configuration. The CSI-RS resources are associated with the measured candidate cells. The measurements are used to determine one or more CSI quantities such as RI, PMI, CQI, and2) The serving cell receiving the CSI reports of one or more candidate cells forwards the CSI reports to the associated target cell / DU directly or indirectly via the CU.

[0145] UE Procedure:

[0146] In one example embodiment:- the UE receiving a configuration of CSI measurement resources, a reporting configuration wherein the configuration is associated with LTM cell switch operation;- the UE determining to perform CSI acquisition as part of the LTM cell switch procedure or associated with the LTM cell switch procedure;- the UE performing CSI acquisition of at least one candidate for LTM cells switch- The UE receiving an request (from target LTM cell) to provide a CSI report to target cell (current serving cell): wherein the CSI reported by the UE is based on the CSI obtained prior to cell switch and / or;- the UE providing an indication that it is able / has acquired CSI prior to cell switch.

[0147] In one example embodiment in accordance with example embodiments of the invention, the UE may be configured for CSI acquisition as part of the LTM cell switch with CSI resources that are part of the LTM configuration: o the CSI acquisition comprising of determining at least one measurement resource and reporting configuration associated with CSI acquisition for an LTM candidate cell.

[0148] In one example embodiment in accordance with example embodiments of the invention, the UE may determine to perform CSI acquisition (i.e. CSI measurements) for an LTM candidate cell based on a certain condition, wherein the condition may be one of: o after receiving a TCI State activation command that activates at least one TCI state for a LTM candidate cell; o alternatively, after receiving a PDCCH order for triggering early UL sync ( PDCCH ordered RACH) or after performing (the RACH transmission) to candidate cell; o alternatively, after receiving a PDCCH order for the LTM candidate cell for which the TCI State activation command has activated at least one TCI state for a LTM candidate cell; o after receiving a cell switch command to a candidate cell; o after receiving a cell switch command that may have indication that triggers the CSI acquisition for the LTM candidate cell;o after performing UE-based TA acquisition for the LTM candidate cell. o after receiving a cell switch command to a candidate cell that comprises an indication of a TCI state (downlink or joint uplink and downlink) for the candidate cell.

[0149] In one example embodiment in accordance with example embodiments of the invention, upon determining that that UE is configured to acquire CSI, the UE may determine the resource and / or QCL assumption for the reference signal used for performing CSI acquisition: o the CSI resource or resources listed in LTM candidate cell configuration associated with the LTM candidate cell for which the UE has determined to acquire CSI; o the CSI resource associated with the activated TCI State for cell switching (i.e. the configured resource for which the active TCI State is a QCL source); o the CSI resource associated with the LTM CSI acquisition and for which the activated TCI state provides a QCL source i.e. the UE expects the activated TCI State to provide QCL source for the measurement resource for CSI acquisition; o the CSI resource for which QCL source TCI state contains at least one of QCL source reference signals associated with the SSB / CSLRS indicated in the PDCCH order; o the CSI resource for which QCL source TCI state contains at least one of QCL source reference signals associated with the SSB / CSLRS used for UE-based TA acquisition;o In any of the above the QCL source may be the reference signal included in the indicated TCI state in the CSC (cell switch command).In any of the examples herein the QCL source reference signal may provide one or more of the QCL types: typeA, typeB, typeC or typeD. The QCL type may be provided for the another / target signal such as CSI-RS (or SSB for CSI acquisition).In any of the examples herein the QCL source reference signal.

[0150] In one example embodiment in accordance with example embodiments of the invention, if the UE is configured with CSI acquisition (e.g., early CSI acquisition for a candidate cell), upon the cell switch to a candidate target cell, it shall be able to provision the reporting of CSI measurements to the target cell (new serving cell after the cell switch): o upon request by the target cell after the cell switch based on the LTM CSI resources after the cell switch: if the DCI scheduling the dynamic grant (scheduling LTM target cell) indicates the CSI request, if the first DCI after the UE has performed the first uplink transmission indicates CSI request, if the DCI acknowledging the provisioned first uplink message (RRC Complete message) requests the CSI, if the DCI indicates a CSI request within the X milliseconds after cell switchIf the DCI indicates certain codepoint in “CSI request” field associated with LTM CSI acquisition,If the DCI indicates (aperiodic) CSI report request but with no linked measurement resource - UE may send the measurement report (no requirement on CSI reference resource or no time delay required for measurement),If the DCI indicates (aperiodic) CSI report, and the resource is associated / linked with a LTM CSI resource - UE may send the measurement report (no requirement on CSI reference resource or delay requirement for measurement); o by default, on the UL SCH resources (indicated by the LTM configured grant); o by default, on the dynamically scheduled UL SCH resources by the target cell; o in one option, the UE may be configured to send the CSI in the RRC Reconfiguration complete message (then later CU can forward the CSI information to the target DU) - for e.g., when cell switch command indicates CSI request and CG / DG (configured grant / dynamic grant) based RACH-less cell switch is performed or / and DG allocating the first uplink message in RACH-less cell switch indicate CSI request; o in one option, the source cell may send an indication to the target cell in the cell switch notification about whether CSI acquisition was triggered or not.

[0151] In one example embodiment, the configured grant may refer to the configured grant for LTM cell switch. The configured grant may (periodic) resource configured to be available for uplink transmission. In some examples, the configured grant may be used for provision of the CSI measurement report.

[0152] In one example embodiment the dynamic grant may refer to network scheduled uplink resource (dynamically scheduled using DCI, downlink control information).

[0153] In one example embodiment in accordance with example embodiments of the invention, if the UE is configured with periodic CSI reporting in the LTM target cell the UE is expected / shall provide the obtained CSI measurements in the first (possible) periodic reporting occasion or until the UE has acquired CSI in the target cell according to the periodic CSI reporting configuration.

[0154] In one example embodiment in accordance with example embodiments of the invention, the UE is configured to continue to perform CSI acquisition on the target cell based on at least one CSI measurement resource that is associated with: o the LTM CSI acquisition resource

[0155] In one example embodiment in accordance with example embodiments of the invention, the UE may indicate in the RRC reconfiguration complete message or Message 3 of a random access procedure ( e.g. when RACH-based cell switch is performed) that it has acquired CSI for the target cell ( CU may indicate the corresponding DU).

[0156] In one example in accordance with example embodiments of the invention, the reporting configuration may comprise of: o LTM CSI Report configuration with CSI quantities such as Channel Quality Indicator (CQI), precoding matrix indicator (PMI), CSLRS resource indicator (CRI), SS / PBCH Block Resource indicator (SSBRI), layer indicator (LI), rank indicator (RI), Ll-RSRP, Ll-SINR, Capabilityindex or time-domain channel properties (TDCP).The serving cell reporting configuration applied for CSI reporting for LTM; o or the reporting configuration is provided in the LTM configuration.

[0157] FIG. 14 shows An example showing some proposed options for Candidate Cell CSI acquisition.

[0158] Examples in accordance with example embodiments of the invention of signaling are shown and / or identified as “Novel” in FIG. 14.

[0159] These novel operations in accordance with example embodiments of the invention as shown in FIG. 14 include: the configuration of CSLRSs and reporting config as a part of the LTM configuration;Triggering of CSI acquisition based on TCI activation or PDCCH ordered RACH or Cell Switch Command;Selection of CSI-RSs based on active TCI state or SSB used for RACH transmission or indicated TCI state;CSI reporting of CSI measurements performed as a part of the LTM procedure to the target cell after the receiving the DCI from the target cell.

[0160] FIG. 16A and FIG. 16B each show a method in accordance with example embodiments of the invention which may be performed by an apparatus.

[0161] FIG. 16A illustrates operations which may be performed by a device such as, but not limited to, a device such as a user equipment device, such as the UE 10 as in FIG. 15. As shown in block 1610 of FIG. 16A there is receiving communications from a source cell of a communication network, comprising a transmission configuration activation command for a target candidate cell. As shown in block 1620 of FIG. 16 A, wherein the transmission configuration activation command for the target candidate cell is for performing, based on completion of at least one condition, channel state information measurements for a triggered mobility operation for user equipment from the source cell to the target candidate cell. As shown in block 1630 of FIG. 16A there is, based on a channel state information acquisition configuration received in the communications from the source cell, performing at least one channel state information measurement acquisition on the target candidate cell. Then in block 1640 of FIG. 16A there is reporting to the target candidate cell, information comprising measurements of channel state information resources on the target candidate cell for performing the triggered mobility operation.

[0162] In accordance with an example embodiment of the invention as described in the paragraph above, wherein the transmission configuration activation command is received at least one of: prior to the cell switch command that switches the UE to the target candidate cell; or the transmission configuration activation command isreceived in the cell switch command, the transmission configuration activation command indicating a target transmission configuration indicator state for the target candidate cell.

[0163] In accordance with an example embodiment of the invention as described in the paragraphs above, there is receiving communications from a source cell of a communication network, comprising a transmission configuration activation command for a target candidate cell, wherein the transmission configuration activation command for the target candidate cell is for performing, based on completion of at least one condition, channel state information measurements for a triggered mobility operation for user equipment from the source cell to the target candidate cell, and based on a channel state information acquisition configuration received in the communications from the source cell, perform at least one channel state information measurement acquisition on the target candidate cell; and reporting to the target candidate cell, information comprising measurements of channel state information resources on the target candidate cell for performing the triggered mobility operation.

[0164] In accordance with an example embodiment of the invention as described in the paragraphs above, wherein the triggered mobility operation is a lower layer triggered mobility operation that is triggered after the receiving downlink control information from the target candidate cell, and wherein the reporting is performed one of upon or after the cell switch to the target candidate cell.

[0165] In accordance with an example embodiment of the invention as described in the paragraphs above, wherein the at least one condition is based on at least one of the at least one transmission configuration indicator state for the target cell is activated after receiving a physical downlink control channel ordered random access, or a physical downlink control channel ordered random access for the target candidate cell, or a physical downlink control channel ordered random access for the target candidate cell for which the transmission configuration activation command has activated at least one transmission configuration indicator state for the target candidate cell, or the at least one transmission configuration indicator state for the target cell is indicated in the cell switch command or the transmission configuration activation command has activated at least one transmission configuration indicator state for the target candidate cell.

[0166] In accordance with an example embodiment of the invention as described in the paragraphs above, wherein the transmission configuration indicator state comprises at least one of quasi co-location source for at least one channel state information reference signal associated with a synchronization signal block or a channel state information reference signal used for a timing advance acquisition

[0167] In accordance with an example embodiment of the invention as described in the paragraphs above, there is selecting one of quasi co-location source reference signal for the at least one channel state reference signal, or channel state information reference signals for performing the at least one channel state information measurement acquisition.

[0168] In accordance with an example embodiment of the invention as described in the paragraphs above, wherein the quasi co-location source for the at least one channel state information reference signal is determined based on at least one of: at least one reference signal included in the activated transmission configuration indicator state for the target candidate cell, at least one reference signal included in the indicated transmission configuration indicator state in the cell switch command for the target candidate cell is a target at least one reference signal of the physical downlink control channel order for the target candidate cell, a target at least one reference signal of the physical downlink control channel order for the target candidate cell for which the transmission configuration activation command has activated at least one transmission configuration indicator state for the target candidate cell.

[0169] In accordance with an example embodiment of the invention as described in the paragraphs above, wherein reporting the information comprising measurements of Channel state information resources on the target candidate cell is sent with a channel state information acquisition flag.

[0170] In accordance with an example embodiment of the invention as described in the paragraphs above, there is receive from the target candidate cell a physical downlink control channel downlink configuration indicator indicating channel state information acquisition and an uplink grant, wherein reporting the information comprising measurements of channel state information resources on the target candidate cell is using the uplink grant.

[0171] In accordance with an example embodiment of the invention as described in the paragraphs above, there is determining at least one of the channel state information resource or a quasi co-location source reference signal used for performing the at least one channel state information measurement acquisition comprising at least one of: the channel state information resources in the target candidate cell or channel state resources listed in a target candidate cell configuration associated with the target candidate cell, the channel state information resources in the target candidate cell associated with an activated transmission configuration indicator state for the triggered lower layer mobility operation, the channel state information resources in the target candidate cell associated with the triggered lower layer mobility operation and for which an activated transmission configuration state provides a quasi co-location source reference signal, the channel state information resources in the target candidate cell for which at least one transmission configuration indicator state contains at least one of quasi co-location source reference signals associated with a synchronization signal block or a channel state information reference signal indicated in the physical downlink control channel order, or the channel state information resources in the target candidate cell for which at least one transmission configuration indicator state contains at least one of quasi co-location source reference signals associated with a synchronization signal block or a channel state information reference signal used for a timing advance acquisition, wherein in the quasi co-location source may be the reference signal included in the indicated transmission configuration indicator.

[0172] In accordance with an example embodiment of the invention as described in the paragraphs above, wherein the activated transmission configuration indicator state provides a quasi co-location source reference signal that the activated transmission configuration indicator transmission configuration indicator state to provide quasi colocation source reference signal for the measurement resource for channel state indicator acquisition.

[0173] In accordance with an example embodiment of the invention as described in the paragraphs above, wherein the reporting to the target candidate cell for the triggered lower layer mobility operation is performed based on at least one of: upon or after the triggered lower layer mobility operation to the target candidate cell, upon request by the target candidate cell after the triggered mobility operation to the target candidate cell, ifdownlink control information based on scheduling a dynamic grant by the target cell indicates a channel state information request, if the first downlink control information by the target cell after a first uplink transmission indicates at least one channel state information acquisition request, if the downlink control information acknowledging a provisioned first uplink message requests at least one channel state information acquisition, if downlink control information indicates a at least one channel state information acquisition request within the X milliseconds after a triggered lower layer mobility operation to the target candidate cell, If downlink control information indicates certain codepoint in a field associated with a channel state information acquisition, or If the downlink control information indicates a channel state information report request with no linked measurement resource, if the downlink control information indicates a channel state information report request.

[0174] In accordance with an example embodiment of the invention as described in the paragraphs above, there is sending the information comprising measurements of channel state information resources on the target candidate cell at least one of: on uplink resources indicated by a configured grant, on a dynamically scheduled uplink resource, or in a radio resource control reconfiguration complete message.

[0175] In accordance with an example embodiment of the invention as described in the paragraphs above, there is sending the information comprising measurements of channel state information resources on the target candidate cell based on a periodic channel state information reporting configuration to the target candidate cell, to provide obtained channel state information measurements in a first periodic reporting occasion or until channel state information is acquired in the target candidate cell according to the periodic channel state information reporting configuration.

[0176] In accordance with an example embodiment of the invention as described in the paragraphs above, there is sending the information comprising measurements of channel state information resources on the target candidate cell based on the latest channel state measurements performed before or upon the triggered mobility operation for user equipment from the source cell to the target candidate cell.

[0177] In accordance with an example embodiment of the invention as described in the paragraphs above, there is indicating in a radio resource control reconfiguration complete message or message 3 of the random access procedure that channel state information is acquired for the target candidate cell.

[0178] In accordance with an example embodiment of the invention as described in the paragraphs above, wherein the channel state information acquisition configuration received in the communications from the source cell comprises channel state information quantities based on at least one of: a channel quality indicator, a precoding matrix indicator, a channel state information reference signal resource indicator, a synchronization signal block or a channel state information reference signal, a layer indicator, a rank indicator, or a capability index or time-domain channel properties.

[0179] In accordance with an example embodiment of the invention as described above there is an apparatus comprising: means for receiving (one or more transceivers 10D; MEM 10B; PROG 10C; and DP lOA as in FIG. 15) communications from a source cell of a communication network, comprising a transmission configuration activation command for a target candidate cell, wherein the transmission configuration activation command for the target candidate cell is for performing, based on completion of at least one condition, channel state information measurements for a triggered mobility operation for user equipment from the source cell to the target candidate cell, and means, based on a channel state information acquisition configuration received in the communications from the source cell, for performing (one or more transceivers 10D; MEM 10B; PROG 10C; and DP 10A as in FIG. 15) at least one channel state information measurement acquisition on the target candidate cell; and means for reporting (one or more transceivers 10D; MEM 10B; PROG 10C; and DP 10A as in FIG. 15) to the target candidate cell, information comprising measurements of channel state information resources on the target candidate cell for performing the triggered mobility operation.

[0180] In the example aspects according to the paragraph above, wherein at least the means for receiving, performing, and / or reporting comprises a non-transitory computer readable medium [MEM 10B as in FIG. 15] encoded with a computer program [PROG 10C as in FIG. 15] executable by at least one processor [DP 10A as in FIG. 15],

[0181] FIG. 16B illustrates operations which may be performed by a device such as, but not limited to, a device such as network node (e.g., the NN 12 and / or NN 13 as in FIG. 15). As shown in block 1650 of FIG. 16B there is communicating with a user equipment of a communication network based on a channel state information acquisition configuration, information for performing a triggered lower layer mobility operation for a cell switch of the user equipment from a source cell to the target candidate cell. As shown in block 1660 of FIG. 16B there is communicating with the user equipment a transmission configuration activation command for performing, based on completion of at least one condition, channel state information measurements for the triggered lower layer mobility operation for the user equipment from the source cell to the target candidate cell. Then as shown in block 1670 of FIG. 16B wherein the channel state information reporting is communicated one of upon or after the cell switch to the target candidate cell.

[0182] In accordance with the example embodiments as described in the paragraph above, wherein there is communicating with a user equipment of a communication network based on a channel state information acquisition configuration, information for performing a triggered lower layer mobility operation for a cell switch of the user equipment from a source cell to the target candidate cell; and communicating with the user equipment a transmission configuration activation command for performing, based on completion of at least one condition, channel state information measurements for the triggered lower layer mobility operation for the user equipment from the source cell to the target candidate cell, wherein the channel state information reporting is communicated one of upon or after the cell switch to the target candidate cell.

[0183] In accordance with the example embodiments as described in the paragraphs above, wherein the at least one condition is based on at least one of the at least one transmission configuration indicator state for the target candidate cell is activated, or a physical downlink control channel order for the target candidate cell for which the transmission configuration indicator state activation command has activated at least one transmission configuration indicator state for the target candidate cell, or the at least one transmission configuration indicator state for the target cell is indicated in the cell switch command.

[0184] In accordance with the example embodiments as described in the paragraphs above, wherein the communicating comprises at least one of a configuration activation or indication command for the target candidate cell, and wherein the transmission configuration activation command for a target candidate cell is for performing, based on completion of at least one condition, channel state information measurements for a triggered mobility operation for user equipment from the source cell to a target candidate cell.

[0185] In accordance with the example embodiments as described in the paragraphs above, wherein the triggered lower layer mobility operation is a lower layer triggered mobility operation that is triggered after downlink control information from the target candidate cell is sent, and wherein the reporting is configured to be performed upon or after the cell switch to the target candidate cell.

[0186] In accordance with the example embodiments as described in the paragraphs above, wherein reporting the information comprising measurements of channel state information resources on the target candidate cell is using an uplink grant.

[0187] In accordance with the example embodiments as described in the paragraphs above, wherein the information comprising measurements of channel state information resources further comprises a channel state information acquisition flag to the target candidate cell for performing the triggered mobility operation.

[0188] In accordance with the example embodiments as described in the paragraphs above, wherein the perform at least one channel state information measurement acquisition on a target candidate cell is performed at least one of: upon or after the triggered mobility operation to the target candidate cell, upon request by the target candidate cell after the triggered mobility operation to the target candidate cell, if downlink control information based on scheduling a dynamic grant that indicates a channel state information request, if the first downlink control information after a first uplink transmission indicates at least one channel state information acquisition request, if the downlink control information acknowledging a provisioned first uplink message requests at least one channel state information acquisition, if downlink control information indicates a at least one channel state information acquisition request within the X milliseconds after triggered mobility operation to the target candidate cell, If downlink control information indicates certain codepoint in afield associated with a channel state information acquisition, or If the downlink control information indicates a channel state information report request with no linked measurement resource.

[0189] In accordance with the example embodiments as described in the paragraphs above, wherein there is receiving information comprising measurements of channel state information resources on the target candidate cell at least one of on uplink resources indicated by a configured grant, on a dynamically scheduled uplink resource, or in a radio resource control reconfiguration complete message, or in a message 3 of the random access procedure.

[0190] In accordance with the example embodiments as described in the paragraphs above, wherein there is receiving information comprising measurements of channel state information resources on the target candidate cell based on a periodic channel state information reporting configuration to the target candidate cell, to provide obtained channel state information measurements in a first periodic reporting occasion or until channel state information is acquired in the target candidate cell according to the periodic channel state information reporting configuration.

[0191] In accordance with the example embodiments as described in the paragraphs above, wherein there is receiving in a radio resource control reconfiguration at least one of a complete message or message 3 that channel state information for the target candidate cell.

[0192] In accordance with the example embodiments as described in the paragraphs above, wherein the channel state information acquisition configuration comprises channel state information quantities based on at least one of a channel quality indicator, a precoding matrix indicator, a channel state information reference signal resource indicator, a synchronization signal block or a channel state information reference signal, a layer indicator, a rank indicator, or a capability index or time-domain channel properties.

[0193] In the example aspects according to the paragraph above, wherein at least the means for receiving, performing, and / or reporting comprises a non-transitory computer readable medium [MEM 12B and / or MEM 13B as in FIG. 15] encoded with a computerprogram [PROG 12C and / or PROG 13C as in FIG. 15] executable by at least one processor [DP 12A and / or DP 13A as in FIG 15],

[0194] In accordance with an example embodiment of the invention as described above there is an apparatus comprising: means for communicating with a user equipment of a communication network based on a channel state information acquisition configuration, information for performing a triggered lower layer mobility operation for a cell switch of the user equipment from a source cell to the target candidate cell; and means for communicating with the user equipment a transmission configuration activation command for performing, based on completion of at least one condition, channel state information measurements for the triggered lower layer mobility operation for the user equipment from the source cell to the target candidate cell, wherein the channel state information reporting is communicated one of upon or after the cell switch to the target candidate cell.

[0195] In the example aspects according to the paragraph above, wherein at least the means for communicating comprises a non-transitory computer readable medium [MEM 12B and / or MEM 13B as in FIG. 15] encoded with a computer program [PROG 12C and / or PROG 13C as in FIG. 15] executable by at least one processor [DP 12A and / or DP 13A as in FIG. 15],

[0196] It is noted that computer-implemented inventions (CII) may be claimed as apparatus claims, method claims, and software claims. In some jurisdictions, such as in Europe, signal claims can also be made. In the U.S., a software claim must be claimed as a non-transitory computer program product or a non-transitory computer readable medium.

[0197] 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).

[0198] In other jurisdictions, a software claim can be claimed as a computer program, a data structure, and / or a computer readable medium.

[0199] Further, in accordance with example embodiments of the invention there is circuitry for performing operations in accordance with example embodiments of the invention as disclosed herein. This circuitry can include any type of circuitry including content coding circuitry, content decoding circuitry, processing circuitry, image generation circuitry, data analysis circuitry, etc.). Further, this circuitry can include discrete circuitry, application-specific integrated circuitry (ASIC), and / or field-programmable gate array circuitry (FPGA), etc. as well as a processor specifically configured by software to perform the respective function, or dual-core processors with software and corresponding digital signal processors, etc.). Additionally, there are provided necessary inputs to and outputs from the circuitry, the function performed by the circuitry and the interconnection (perhaps via the inputs and outputs) of the circuitry with other components that may include other circuitry in order to perform example embodiments of the invention as described herein.

[0200] In accordance with example embodiments of the invention as disclosed in this application this application, the “circuitry” provided can include at least one or more or all of the following:(a) hardware-only circuit implementations (such as implementations in only analog and / or digital circuitry);(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, such as functions or operations in accordance with example embodiments of the invention as disclosed herein); 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.”

[0201] In accordance with example embodiments of the invention, there is adequate circuitry for performing at least novel operations in accordance with example embodiments of the invention as disclosed in this application, this 'circuitry' as may be used herein refers to at least the following:(a) hardware-only circuit implementations (such as implementations in only analog and / or digital circuitry); and(b) to combinations of circuits and software (and / or firmware), such as (as applicable): (i) to a combination of processor(s) or (ii) to portions of processor(s) / 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) to circuits, such as a microprocessor(s) or a portion of a microprocessor s), that require software or firmware for operation, even if the software or firmware is not physically present.

[0202] 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" would also cover an implementation of merely a processor (or multiple processors) or portion of a processor and its (or their) accompanying software and / or firmware. The term "circuitry" would also cover, for example and if applicable to the particular claim element, a baseband integrated circuit or applications processor integrated circuit for a mobile phone or a similar integrated circuit in a server, a cellular network device, or other network device.

[0203] In general, the various embodiments may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. For example, some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or othercomputing device, although the invention is not limited thereto. While various aspects of the invention may be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods 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.

[0204] Embodiments of the inventions may be practiced in various components such as integrated circuit modules. The design of integrated circuits is by and large a highly automated process. Complex and powerful software tools are available for converting a logic level design into a semiconductor circuit design ready to be etched and formed on a semiconductor substrate.

[0205] The word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. All of the embodiments described in this Detailed Description are exemplary embodiments provided to enable persons skilled in the art to make or use the invention and not to limit the scope of the invention which is defined by the claims.

[0206] The foregoing description has provided by way of exemplary and nonlimiting examples a full and informative description of the best method and apparatus presently contemplated by the inventors for carrying out the invention. However, various modifications and adaptations may become apparent to those skilled in the relevant arts in view of the foregoing description, when read in conjunction with the accompanying drawings and the appended claims. However, all such and similar modifications of the teachings of example embodiments of this invention will still fall within the scope of this invention.

[0207] It should be noted that the terms "connected," "coupled," or any variant thereof, mean any connection or coupling, either direct or indirect, between two or more elements, and may encompass the presence of one or more intermediate elements between two elements that are "connected" or "coupled" together. The coupling or connectionbetween the elements can be physical, logical, or a combination thereof. As employed herein two elements may be considered to be "connected" or "coupled" together by the use of one or more wires, cables and / or printed electrical connections, as well as by the use of electromagnetic energy, such as electromagnetic energy having wavelengths in the radio frequency region, the microwave region and the optical (both visible and invisible) region, as several non-limiting and non-exhaustive examples.

[0208] Furthermore, some of the features of the preferred embodiments of this invention could be used to advantage without the corresponding use of other features. As such, the foregoing description should be considered as merely illustrative of the principles of the invention, and not in limitation thereof.

Claims

CLAIMS1. An apparatus, comprising: at least one processor; and at least one memory storing instructions, that when executed by the at least one processor, cause the apparatus at least to: receive communications from a source cell of a communication network, comprising a transmission configuration activation command for a target candidate cell, wherein the transmission configuration activation command for the target candidate cell is for performing, based on completion of at least one condition, channel state information measurements for a triggered mobility operation for user equipment from the source cell to the target candidate cell; based on a channel state information acquisition configuration received in the communications from the source cell, perform at least one channel state information measurement acquisition on the target candidate cell; and report to the target candidate cell, information comprising measurements of channel state information resources on the target candidate cell for performing the triggered mobility operation.

2. The apparatus of claim 1, wherein the transmission configuration activation command is received at least one of : prior to the cell switch command that switches the UE to the target candidate cell; or the transmission configuration activation command is received in the cell switch command, the transmission configuration activation command indicating a target transmission configuration indicator state for the target candidate cell.

3. The apparatus of claim 1, wherein the triggered mobility operation is a lower layer triggered mobility operation that is triggered after the receiving downlink control information from the target candidate cell, and wherein the reporting is performed one of upon or after the cell switch to the target candidate cell.

4. The apparatus of claim 1, wherein the at least one condition is based on at least one of: the at least one transmission configuration indicator state for the target cell is activated after receiving a physical downlink control channel ordered random access, a physical downlink control channel ordered random access for the target candidate cell is triggered, or a physical downlink control channel ordered random access for the target candidate cell for which the transmission configuration activation command has activated at least one transmission configuration indicator state for the target candidate cell, or the at least one transmission configuration indicator state for the target candidate cell is activated, or the at least one transmission configuration indicator state for the target candidate cell is indicated in the cell switch command.

5. The apparatus of claim 4, wherein the transmission configuration indicator state comprises at least one of quasi co-location source for at least one channel state information reference signal associated with a synchronization signal block or a channel state information reference signal used for a timing advance acquisition6. The apparatus of claim 5, wherein the at least one memory is storing instructions, that when executed by the at least one processor, cause the apparatus at least to: select one of quasi co-location source reference signal for the at least one channel state reference signal, or channel state information reference signals for performing the at least one channel state information measurement acquisition.

7. The apparatus of claim 5, wherein the quasi co-location source for the at least one channel state information reference signal is determined based on at least one of: at least one reference signal included in the activated transmission configuration indicator state for the target candidate cell,at least one reference signal included in the indicated transmission configuration indicator state in the cell switch command for the target candidate cell is, a target at least one reference signal of the physical downlink control channel order for the target candidate cell, a target at least one reference signal of the physical downlink control channel order for the target candidate cell for which the transmission configuration activation command has activated at least one transmission configuration indicator state for the target candidate cell.

8. The apparatus of claim 1, wherein reporting the information comprising measurements of channel state information resources on the target candidate cell is sent with a channel state information acquisition flag.

9. The apparatus of claim 8, wherein the at least one memory is storing instructions, that when executed by the at least one processor, cause the apparatus at least to: receive from the target candidate cell a physical downlink control channel downlink configuration indicator indicating channel state information acquisition and an uplink grant, wherein reporting the information comprising measurements of channel state information resources on the target candidate cell is using the uplink grant.

10. The apparatus of claim 7, wherein the at least one memory is storing instructions, that when executed by the at least one processor, cause the apparatus at least to determine at least one of the channel state information resource or a quasi co-location source reference signal used for performing the at least one channel state information measurement acquisition comprising at least one of: the channel state information resources in the target candidate cell or channel state resources listed in a target candidate cell configuration associated with the target candidate cell, the channel state information resources in the target candidate cell associated with an activated transmission configuration indicator state for the triggered lower layer mobility operation,the channel state information resources in the target candidate cell associated with the triggered lower layer mobility operation and for which an activated transmission configuration state provides a quasi co-location source reference signal, the channel state information resources in the target candidate cell for which at least one transmission configuration indicator state contains at least one of quasi co-location source reference signals associated with a synchronization signal block or a channel state information reference signal indicated in the physical downlink control channel order, or the channel state information resources in the target candidate cell for which at least one transmission configuration indicator state contains at least one of quasi co-location source reference signals associated with a synchronization signal block or a channel state information reference signal used for a timing advance acquisition, wherein in the quasi co-location source may be the reference signal included in the indicated transmission configuration indicator.

11. The apparatus of claim 5, wherein the activated transmission configuration indicator state provides a quasi co-location source reference signal that the activated transmission configuration indicator transmission configuration indicator state to provide quasi co-location source reference signal for the measurement resource for channel state indicator acquisition.

12. The apparatus of claim 1, wherein the reporting to the target candidate cell for the triggered lower layer mobility operation is performed based on at least one of: upon or after the triggered lower layer mobility operation to the target candidate cell, upon request by the target candidate cell after the triggered mobility operation to the target candidate cell, if downlink control information based on scheduling a dynamic grant by the target cell indicates a channel state information request, if the first downlink control information by the target cell after a first uplink transmission indicates at least one channel state information acquisition request, if the downlink control information acknowledging a provisioned first uplink message requests at least one channel state information acquisition,if downlink control information indicates a at least one channel state information acquisition request within the X milliseconds after a triggered lower layer mobility operation to the target candidate cell,If downlink control information indicates certain codepoint in a field associated with a channel state information acquisition, orIf the downlink control information indicates a channel state information report request with no linked measurement resource.If the downlink control information indicates a channel state information report request.

13. The apparatus of claim 10, wherein the at least one memory is storing instructions, that when executed by the at least one processor, cause the apparatus at least to send the information comprising measurements of channel state information resources on the target candidate cell at least one of: on uplink resources indicated by a configured grant, on a dynamically scheduled uplink resource, or in a radio resource control reconfiguration complete message.

14. The apparatus of claim 1, wherein the at least one memory is storing instructions, that when executed by the at least one processor, cause the apparatus at least to: send the information comprising measurements of channel state information resources on the target candidate cell based on a periodic channel state information reporting configuration to the target candidate cell, to provide obtained channel state information measurements in a first periodic reporting occasion or until channel state information is acquired in the target candidate cell according to the periodic channel state information reporting configuration.

15. The apparatus of claim 1, wherein the at least one memory is storing instructions, that when executed by the at least one processor, cause the apparatus at least to: send the information comprising measurements of channel state information resources on the target candidate cell based on a latest at least one channel statemeasurement performed before or upon the triggered mobility operation for user equipment from the source cell to the target candidate cell.

16. The apparatus of claim 1, wherein the at least one memory is storing instructions, that when executed by the at least one processor, cause the apparatus at least to: send the information comprising measurements of channel state information resources on the target candidate cell based on the latest channel state measurements performed before or upon the triggered mobility operation for user equipment from the source cell to the target candidate cell.

17. The apparatus of claim 1, wherein the at least one memory is storing instructions, that when executed by the at least one processor, cause the apparatus to at least one of: indicate in a radio resource control reconfiguration complete message or message 3 of the random access procedure that channel state information is acquired for the target candidate cell.

18. The apparatus of claim 1, wherein the channel state information acquisition configuration received in the communications from the source cell comprises channel state information quantities based on at least one of : a channel quality indicator, a precoding matrix indicator, a channel state information reference signal resource indicator, a synchronization signal block or a channel state information reference signal, a layer indicator, a rank indicator, or a capability index or time-domain channel properties.

19. A method, compri sing : receiving communications from a source cell of a communication network, comprising a transmission configuration activation command for a target candidate cell,wherein the transmission configuration activation command for the target candidate cell is for performing, based on completion of at least one condition, channel state information measurements for a triggered mobility operation for user equipment from the source cell to the target candidate cell; based on a channel state information acquisition configuration received in the communications from the source cell, performing at least one channel state information measurement acquisition on the target candidate cell; and reporting to the target candidate cell, information comprising measurements of channel state information resources on the target candidate cell for performing the triggered mobility operation.

20. An apparatus, comprising: at least one processor; and at least one memory storing instructions, that when executed by the at least one processor, cause the apparatus at least to: communicate with a user equipment of a communication network based on a channel state information acquisition configuration, information for performing a triggered lower layer mobility operation for a cell switch of the user equipment from a source cell to the target candidate cell; and communicate with the user equipment a transmission configuration activation command for performing, based on completion of at least one condition, channel state information measurements for the triggered lower layer mobility operation for the user equipment from the source cell to the target candidate cell, wherein the channel state information reporting is communicated one of upon or after the cell switch to the target candidate cell.

21. The apparatus of claim 20, wherein the at least one condition is based on at least one of: the at least one transmission configuration indicator state for the target candidate cell is activated, or a physical downlink control channel order for the target candidate cell for which the transmission configuration indicator state activation command has activated at least one transmission configuration indicator state for the target candidate cell, or the at least onetransmission configuration indicator state for the target cell is indicated in the cell switch command.

22. The apparatus of claim 20, wherein the communicating comprises at least one of a configuration activation or indication command for the target candidate cell, and wherein the transmission configuration activation command for a target candidate cell is for performing, based on completion of at least one condition, channel state information measurements for a triggered mobility operation for user equipment from the source cell to a target candidate cell;23. The apparatus of claim 20, wherein the triggered lower layer mobility operation is a lower layer triggered mobility operation that is triggered after downlink control information from the target candidate cell is sent, and wherein the reporting is configured to be performed upon or after the cell switch to the target candidate cell.

24. The apparatus of claim 23, wherein reporting the information comprising measurements of channel state information resources on the target candidate cell is using an uplink grant.

25. The apparatus of claim 20, wherein the information comprising measurements of channel state information resources further comprises a channel state information acquisition flag to the target candidate cell for performing the triggered mobility operation.

26. The apparatus of claim 20, wherein the perform at least one channel state information measurement acquisition on a target candidate cell is performed at least one of upon or after the triggered mobility operation to the target candidate cell, upon request by the target candidate cell after the triggered mobility operation to the target candidate cell, if downlink control information based on scheduling a dynamic grant that indicates a channel state information request, if the first downlink control information after a first uplink transmission indicates at least one channel state information acquisition request,if the downlink control information acknowledging a provisioned first uplink message requests at least one channel state information acquisition, if downlink control information indicates a at least one channel state information acquisition request within the X milliseconds after triggered mobility operation to the target candidate cell,If downlink control information indicates certain codepoint in a field associated with a channel state information acquisition, orIf the downlink control information indicates a channel state information report request with no linked measurement resource.

27. The apparatus of claim 20, wherein the at least one memory is storing instructions, that when executed by the at least one processor, cause the apparatus at least to: receive information comprising measurements of channel state information resources on the target candidate cell at least one of: on uplink resources indicated by a configured grant, on a dynamically scheduled uplink resource, or in a radio resource control reconfiguration complete message, or in a message 3 of the random access procedure.

28. The apparatus of claim 20, wherein the at least one memory is storing instructions, that when executed by the at least one processor, cause the apparatus at least to: receive information comprising measurements of channel state information resources on the target candidate cell based on a periodic channel state information reporting configuration to the target candidate cell, to provide obtained channel state information measurements in a first periodic reporting occasion or until channel state information is acquired in the target candidate cell according to the periodic channel state information reporting configuration.

29. The apparatus of claim 20, wherein the at least one memory is storing instructions, that when executed by the at least one processor, cause the apparatus to at least one of:receive in a radio resource control reconfiguration at least one of a complete message or message 3 that channel state information for the target candidate cell.

30. The apparatus of claim 20, wherein the channel state information acquisition configuration comprises channel state information quantities based on at least one of : a channel quality indicator, a precoding matrix indicator, a channel state information reference signal resource indicator, a synchronization signal block or a channel state information reference signal, a layer indicator, a rank indicator, or a capability index or time-domain channel properties.

31. A method, compri sing : communicating with a user equipment of a communication network based on a channel state information acquisition configuration, information for performing a triggered lower layer mobility operation for a cell switch of the user equipment from a source cell to the target candidate cell; and communicating with the user equipment a transmission configuration activation command for performing, based on completion of at least one condition, channel state information measurements for the triggered lower layer mobility operation for the user equipment from the source cell to the target candidate cell, wherein the channel state information reporting is communicated one of upon or after the cell switch to the target candidate cell.

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