Activation and deactivation of semi-persistent channel state information reference signals from a candidate cell

Abstract

A method, apparatus and computer program product are provided for signaling techniques for indicating whether a given control message for activation and deactivation of semi-persistent (SP) channel state information signal (CSI-RS) is associated with a CSI-RS of a current serving cell or a layer-triggered mobility (LTM) candidate cell. In the context of a method, the method includes receiving configuration data for a CSI-RS of a cell of a network node, wherein the configuration data indicates a SP CSI-RS resource set for the CSI-RS. The method further includes receiving a control message associated with the CSI- RS of the cell of, wherein at least one field of the control message indicates i) whether the cell is a serving cell or a candidate cell, and ii) whether an activation or a deactivation of the SP CSI-RS resource set applies to the cell.

Description

ACTIVATION AND DEACTIVATION OF SEMI-PERSISTENT CHANNEL STATE INFORMATION REFERENCE SIGNALS FROM A CANDIDATE CELLTECHNICAL FIELD

[0001] An example embodiment relates generally to signaling techniques for indicating whether a given control message for activation and deactivation of semi-persistent (SP) channel state information signal (CSI-RS) is associated with a CSI-RS of a current serving cell or a CSI-RS of a layer 1 / layer 2 triggered mobility (LTM) candidate cell.BACKGROUND

[0002] Common approaches to LTM utilize synchronization signal block (SSB)-based layer-1 (LI) measurements to evaluate the quality of candidate cells for switch decisions. Such approaches typically generate SSB measurements over a narrow bandwidth with long periodicity and wider beams. As a result, SSB-based LTM switching may demonstrate poor time and frequency synchronization with the target cell. Alternative measurements with narrower beam and links may be utilized to improve time and frequency synchronization with the target cell; however, the triggering and reporting of alternative measurements may require alternative signaling approaches. For example, CSI-RS measurements may supplement SSB measurements; however, existing telecommunications approaches lack signaling procedures for enabling LI CSI-RS measurement and reporting for candidate target cells.BRIEF SUMMARY

[0003] A method, apparatus and computer program product are provided in accordance with an example embodiment in order to generate and provision control messages indicative of whether the activation or deactivation of one or more SP CSI-RS resources or one or more SP CSI-RS resource sets, where a resource set contains the indications of one or more resources, applies for a candidate cell or a current serving cell. In various embodiments, the present method, apparatus, and computer program product provide improved solutions for evaluating the quality of candidate cells for cell switch decisions based on CSI-RS measurements. For example, the method, apparatus, and computer program product may enable LI candidate cell measurements using CSI-RSs, including periodic CSI-RSs, SP CSI- RSs, and aperiodic CSI-RSs.

[0004] In some embodiments, the method, apparatus, and computer program product provision the configuration of CSI-RSs to a UE to cause the UE to determine the resource allocation, RS sequence, and other parameters for generating LI measurements (e.g., Ll- RSRP) based on the control message. Further, the method, apparatus, and computer program product may generate and provision a control message indicative of activation and / or deactivation of SP CSI-RSs. In some embodiments, the control message indicates one or more CSLRS resource set identifiers to be activated, deactivated, and / or the like. The serving cells and candidate cells of a network node may each be associated with a different set of CSI-RSs and CSLRS resource sets. Existing approaches to CSLRS-based LI measurement lack means for indicating to the UE whether the activation and / or deactivation of a CSLRS resource set applies to a current serving cell or a candidate cell. To overcome this challenge, the present method, apparatus, and computer program product encode into the control message an indication of whether the control message is associated with a current serving cell’s CSLRSs or one or more CSLRSs of one or more candidate cells. In doing so, the method, apparatus, and computer program product enable use of CSLRS measurements for candidate cell switch decisions, which may facilitate switching the UE with narrower beam and links with better time and frequency synchronization in the target candidate cell as compared to SSB-based approaches.

[0005] In at least one embodiment, a method is provided that includes receiving configuration data for at least one CSLRS of at least one cell of a network node, wherein the configuration data indicates at least one SP CSLRS resource set for the respective CSI RS; and receiving a control message associated with the at least one CSLRS of the at least one cell of the network node, wherein at least one field of the control message indicates i) whether the at least one cell is a serving cell or a candidate cell, and ii) whether an activation or a deactivation of the at least one SP CSLRS resource set applies to the at least one cell.

[0006] In some embodiments, the method further includes generating at least one LI measurement on the at least one CSLRS of the at least one cell of based at least in part on the control message; and provisioning to the network node a report comprising the at least one LI measurement on the at least one CSLRS for the at least one cell. In some embodiments, the method further includes executing an LTM cell switch from a current serving cell of the network node to a respective cell of the at least one cell in response to a second control message from the network node, wherein the second control message is based at least in part on the report.

[0007] In some embodiments, the at least one field comprises a cell identifier bit field comprising an identifier for the at least one cell. In some embodiments, the at least one field further comprises a second bit field configurable between a first value and a second value; in the first value, the second bit field indicates the at least one cell is a serving cell; and in the second value, the second bit field indicates the at least one cell is a candidate cell. In some embodiments, in the second value, the second bit field indicates that the candidate cell is an LTM candidate cell. In some embodiments, the at least one field further comprises a third bit field comprising a bitstring; and in the second value, the second bit field further indicates that the bitstring of the third bit field comprises an identifier for a respective SP CSI-RS resource set of the at least one SP CSI-RS resource set for the respective CSI-RS of the at least one cell.

[0008] In some embodiments, the at least one field further comprises an activation / deactivation (A / D) field configurable between the first value and the second value; in the first value, the A / D field indicates that the respective SP CSI-RS resource set is activated for the at least one cell; and in the second value, the A / D bit field indicates that the respective SP CSI-RS resource set is deactivated for the at least one cell. In some embodiments, the respective SP CSI-RS resource set comprises an SP -nonzero power (NZP) CSI-RS resource set associated with the identifier for the at least one cell.

[0009] In some embodiments, the at least one field further comprises an inference measurement (IM) field. In some embodiments, in the second value, the second bit field further indicates that the IM field is set to zero for the at least one cell. In some embodiments, the at least one field further comprises an SP CSI-RS resource set identifier field; and in the second value, the second bit field further indicates that the IM field and the SP CSI-RS resource set identifier field are at least one of set to zero for the at least one cell, not encoded, or to be ignored. In some embodiments, the SP CSI-RS resource set identifier field comprises a bitstring; and the IM field is configurable between the first value and the second value. In some embodiments, in the second value, the second bit field and the IM field indicate that the bitstring of the SP CSI-RS resource set identifier field comprises an index of a SP CSI- IM resource set associated with the identifier for the at least one cell.

[0010] In some embodiments, the at least one field further comprises at least one transmission configuration indication (TCI) field comprising a respective bitstring; and in the second value, the second bit field indicates that the respective bitstring of the at least one TCI field comprises a TCI state identifier for the at least one cell. In some embodiments, the at least one field further comprises a third field associated with bandwidth part (BWP)information; in the second value, the second bit field indicates at least one of: the third field is at least one of i) not encoded or ii) to be ignored in the generating of the at least one LI measurement; the activation or deactivation of the at least one SP CSLRS resource set applies to an active BWP for the current serving cell; or the activation or deactivation of the at least one SP CSLRS resource set applies to a BWP for the at least one cell. In some embodiments, the at least one field further comprises a BWP field comprising a bitstring; in the second value, the second bit field indicates that the bitstring comprises a downlink (DL) BWP identifier for the current serving cell; and the method further comprises: applying the active DL BWP for the current serving cell to at least one LI measurement based at least in part on the DL BWP identifier.

[0011] In some embodiments, the at least one field further comprises a third field associated with BWP information; and in the second value, the second bit field indicates: the third field is at least one of to be ignored in generation of at least one LI measurement; and the method further comprises: applying a DL BWP of a primary cell of the network node to the at least one LI measurement. In some embodiments, the control message embodies a medium access control (MAC) control element (CE). In some embodiments, the control message comprises a logical channel identifier. In some embodiments, the network node embodies a gNodeB.

[0012] As further described below, in some embodiments, one or more operations of the above-described methods are performed by an apparatus including at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to perform the one or more operations. For example, an apparatus may include at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to (i) receive configuration data for at least one CSLRS of at least one cell of a network node, wherein the configuration data indicates at least one SP CSLRS resource set for the respective CSI RS; and (ii) receiving a control message associated with the at least one CSLRS of the at least one cell of the network node, wherein at least one field of the control message indicates a) whether the at least one cell is a serving cell or a candidate cell, and b) whether an activation or a deactivation of the at least one SP CSLRS resource set applies to the at least one cell. In the same example, the instructions, in execution with the at least one processor, may further cause the apparatus to (i) generate at least one LI measurement on the at least one CSLRS of the at least one cell of based at least in part on the control message; and (ii) provision to the network node a report comprising the at least one LI measurement on the at least one CSLRS for the at least one cell. Continuing the example, the instructions, in execution with the at least oneprocessor, may further cause the apparatus to execute an LTM cell switch from a current serving cell of the network node to a respective cell of the at least one cell in response to a second control message from the network node, wherein the second control message is based at least in part on the report. In the same example, the apparatus may also perform other operations and / or embody additional aspects of the above-described methods.

[0013] In various embodiments, as further described below, provided herein is a computer program product including at least one non-transitory computer-readable storage medium having computer-executable program code instructions stored therein, the computerexecutable program code instructions including program code instructions configured for performing one or more operations and / or embody additional aspects of the above-described methods. For example, a computer program product may include at least one non-transitory computer-readable storage medium having computer-executable program code instructions stored therein, the computer-executable program code instructions including program code instructions configured to (i) receive configuration data for at least one CSI-RS of at least one cell of a network node, wherein the configuration data indicates at least one SP CSI-RS resource set for the respective CSI RS; and (ii) receiving a control message associated with the at least one CSI-RS of the at least one cell of the network node, wherein at least one field of the control message indicates a) whether the at least one cell is a serving cell or a candidate cell, and b) whether an activation or a deactivation of the at least one SP CSI-RS resource set applies to the at least one cell. In the same example, the program code instructions may be further configured to (i) generate at least one LI measurement on the at least one CSI-RS of the at least one cell of based at least in part on the control message; and (ii) provision to the network node a report comprising the at least one LI measurement on the at least one CSI-RS for the at least one cell. Continuing the example, program code instructions may be further configured to execute an LTM cell switch from a current serving cell of the network node to a respective cell of the at least one cell in response to a second control message from the network node, wherein the second control message is based at least in part on the report. In the same example, the program code instructions may also be configured to perform additional operations and / or embody additional aspects of the above-described methods.

[0014] In various embodiments, as further described below, one or more operations of the above-described methods are performed by an apparatus having means for performing the one or more operations. For example, an apparatus may include (i) means for receiving configuration data for at least one CSI-RS of at least one cell of a network node, wherein the configuration data indicates at least one SP CSI-RS resource set for the respective CSI RS;and (ii) means for receiving a control message associated with the at least one CSI-RS of the at least one cell of the network node, wherein at least one field of the control message indicates a) whether the at least one cell is a serving cell or a candidate cell, and b) whether an activation or a deactivation of the at least one SP CSI-RS resource set applies to the at least one cell. In the same example, the apparatus may further include (i) means for generating at least one LI measurement on the at least one CSI-RS of the at least one cell of based at least in part on the control message; and (ii) means for provisioning to the network node a report comprising the at least one LI measurement on the at least one CSI-RS for the at least one cell. Continuing the example, the apparatus may further include means for executing an LTM cell switch from a current serving cell of the network node to a respective cell of the at least one cell in response to a second control message from the network node, wherein the second control message is based at least in part on the report. In the same example, the apparatus may embody additional aspects and / or include additional means for performing additional operations of the above-described methods.

[0015] In at least one embodiment, a second method is provided that includes provisioning to a UE configuration data for at least one CSI-RS of at least one cell, wherein the configuration data indicates at least one SP CSI-RS resource set for the respective CSI RS; and provisioning to the UE a control message associated with the at least one CSI-RS of the at least one cell, wherein at least one field of the control message indicates i) whether the at least one cell is a serving cell or a candidate cell, and ii) whether an activation or a deactivation of the at least one SP CSI-RS resource set applies to the at least one cell.

[0016] In some embodiments, the control message causes the UE to generate at least one LI measurement on the at least one CSI-RS U of the at least one cell of based at least in part on the control message; and the method further comprises: receiving from the UE a report comprising the at least one LI measurement on the at least one CSI-RS for the at least one cell. In some embodiments, the method further comprises provisioning a second control message to the UE to cause the UE to execute an LTM cell switch from a current serving cell to a respective cell of the at least one cell, wherein the second control message is based at least in part on the report.

[0017] In some embodiments, the at least one field comprises a cell identifier bit field comprising an identifier for the at least one cell. In some embodiments, the at least one field further comprises a second bit field configurable between a first value and a second value; in the first value, the second bit field indicates the at least one cell is a serving cell; and in the second value, the second bit field indicates the at least one cell is a candidate cell. Insome embodiments, in the second value, the second bit field indicates that the candidate cell is an LTM candidate cell. In some embodiments, the at least one field further comprises a third bit field comprising a bitstring; and in the second value, the second bit field further indicates that the bitstring of the third bit field comprises an identifier for a respective SP CSI-RS resource set of the at least one SP CSI-RS resource set for the respective CSI-RS of the at least one cell.

[0018] In some embodiments, the at least one field further comprises an A / D field configurable between the first value and the second value; in the first value, the A / D field indicates that the respective SP CSI-RS resource set is activated for the at least one cell; and in the second value, the A / D bit field indicates that the respective SP CSI-RS resource set is deactivated for the at least one cell. In some embodiments, the respective SP CSI-RS resource set comprises an SP-NZP CSI-RS resource set associated with the identifier for the at least one cell. In some embodiments, the at least one field further comprises an IM field. In some embodiments, in the second value, the second bit field further indicates that the IM field is set to zero for the at least one cell. In some embodiments, the at least one field further comprises an SP CSI-RS resource set identifier field; and in the second value, the second bit field further indicates that the IM field and the SP CSI-RS resource set identifier field are at least one of set to zero for the at least one cell, not encoded, or to be ignored.

[0019] In some embodiments, the SP CSI-RS resource set identifier field comprises a bitstring; and the IM field is configurable between the first value and the second value. In some embodiments, in the second value, the second bit field and the IM field indicate that the bitstring of the SP CSI-RS resource set identifier field comprises an index of a SP CSI- IM resource set associated with the identifier for the at least one cell. In some embodiments, the at least one field further comprises at least one transmission configuration indication (TCI) field comprising a respective bitstring; and in the second value, the second bit field indicates that the respective bitstring of the at least one TCI field comprises a TCI state identifier for the at least one cell.

[0020] In some embodiments, the at least one field further comprises a third field associated with BWP information; in the second value, the second bit field indicates at least one of the third field is at least one of i) not encoded or ii) to be ignored in the generating of the at least one LI measurement; the activation or deactivation of the at least one SP CSI-RS resource set applies to an active BWP for the current serving cell; or the activation or deactivation of the at least one SP CSI-RS resource set applies to a BWP for the at least one cell. In some embodiments, the at least one field further comprises a BWP field comprising a bitstring; inthe second value, the second bit field indicates that the bitstring comprises a DL BWP identifier for the current serving cell; and the control message further causes the UE to: apply the active DL BWP for the current serving cell to at least one LI measurement based at least in part on the DL BWP identifier.

[0021] In some embodiments, the at least one field further comprises a third field associated with BWP information; and in the second value, the second bit field indicates: the third field is at least one of to be ignored in generation of at least one LI measurement; and the control message further causes the UE to: apply a DL BWP of a primary cell of to the at least one LI measurement. In some embodiments, the control message embodies a MAC CE. In some embodiments, the control message comprises a logical channel identifier.

[0022] As further described below, in some embodiments, one or more operations of the above-described methods are performed by an apparatus including at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to perform the one or more operations. For example, an apparatus may include at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to (i) provision to a UE configuration data for at least one CSLRS of at least one cell, wherein the configuration data indicates at least one SP CSLRS resource set for the respective CSI RS; and (ii) provision to the UE a control message associated with the at least one CSLRS of the at least one cell, wherein at least one field of the control message indicates a) whether the at least one cell is a serving cell or a candidate cell, and b) whether an activation or a deactivation of the at least one SP CSLRS resource set applies to the at least one cell. In the same example, the instructions, in execution with the at least one processor, may further cause the apparatus to receive from the UE a report comprising the at least one LI measurement on the at least one CSLRS for the at least one cell. Continuing the example, the instructions, in execution with the at least one processor, may further cause the apparatus to provision a second control message to the UE to cause the UE to execute an LTM cell switch from a current serving cell to a respective cell of the at least one cell, wherein the second control message is based at least in part on the report. In the same example, the apparatus may also perform other operations and / or embody additional aspects of the above-described methods.

[0023] In various embodiments, as further described below, provided herein is a computer program product including at least one non-transitory computer-readable storage medium having computer-executable program code instructions stored therein, the computerexecutable program code instructions including program code instructions configured forperforming one or more operations and / or embody additional aspects of the above-described methods. For example, a computer program product may include at least one non-transitory computer-readable storage medium having computer-executable program code instructions stored therein, the computer-executable program code instructions including program code instructions configured to (i) provision to a UE configuration data for at least one CSI-RS of at least one cell, wherein the configuration data indicates at least one SP CSI-RS resource set for the respective CSI RS; and (ii) provision to the UE a control message associated with the at least one CSI-RS of the at least one cell, wherein at least one field of the control message indicates a) whether the at least one cell is a serving cell or a candidate cell, and b) whether an activation or a deactivation of the at least one SP CSI-RS resource set applies to the at least one cell. In the same example, the program code instructions may be further configured to receive from the UE a report comprising the at least one LI measurement on the at least one CSI-RS for the at least one cell. Continuing the example, the program code instructions may be further configured to provision a second control message to the UE to cause the UE to execute an LTM cell switch from a current serving cell to a respective cell of the at least one cell, wherein the second control message is based at least in part on the report. In the same example, the program code instructions may also be configured to perform additional operations and / or embody additional aspects of the above-described methods.

[0024] In various embodiments, as further described below, one or more operations of the above-described methods are performed by an apparatus having means for performing the one or more operations. For example, an apparatus may include (i) means for provisioning to a UE configuration data for at least one CSI-RS of at least one cell, wherein the configuration data indicates at least one SP CSI-RS resource set for the respective CSI RS; and (ii) means for provisioning to the UE a control message associated with the at least one CSI-RS of the at least one cell, wherein at least one field of the control message indicates a) whether the at least one cell is a serving cell or a candidate cell, and b) whether an activation or a deactivation of the at least one SP CSI-RS resource set applies to the at least one cell. In the same example, the apparatus my further comprise means for receiving from the UE a report comprising the at least one LI measurement on the at least one CSI-RS for the at least one cell. Continuing the example, the apparatus may further include means for provisioning a second control message to the UE to cause the UE to execute an LTM cell switch from a current serving cell to a respective cell of the at least one cell, wherein the second control message is based at least in part on the report. In the same example, the apparatus mayembody additional aspects and / or include additional means for performing additional operations of the above-described methods.BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Having thus described certain example embodiments of the present disclosure in general terms, reference will hereinafter be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein:

[0026] FIG. 1 illustrates an example of a communication system in which an example embodiment of the present disclosure may be implemented;

[0027] FIG. 2 illustrates a block diagram of an apparatus that may be configured in accordance with an example embodiment of the present disclosure;

[0028] FIGS. 3A-3B illustrate, respectively, a legacy control message and an example control message in accordance with at least an example embodiment of the present disclosure;

[0029] FIGS. 4A-4B illustrate a signal diagram for CSI-RS-based LTM in accordance with an example embodiment of the present disclosure;

[0030] FIG. 5 is an example flowchart of a CSI-RS resource signaling process that may be performed by a UE in accordance with an example embodiment of the present disclosure;

[0031] FIG. 6 is an example flowchart of a CSI-RS resource signaling process that may be performed by a network node in accordance with an example embodiment of the present disclosure;

[0032] FIG. 7 illustrates a signal diagram for S SB-based LTM according to prior approaches.DETAILED DESCRIPTION

[0033] Some embodiments will now be described more fully hereinafter with reference to the accompanying drawings, in which some, but not all, embodiments are shown. Indeed, various embodiments may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will satisfy applicable legal requirements. Like reference numerals refer to like elements throughout. As used herein, the terms “data,” “content,” “information,” and similar terms may be used interchangeably to refer to data capable of being transmitted,received and / or stored in accordance with the described embodiments. Thus, use of any such terms should not be taken to limit the spirit and scope of the embodiments.

[0034] Additionally, as used herein, the term ‘circuitry’ refers to (a) hardware-only circuit implementations (e.g., implementations in analog circuitry and / or digital circuitry); (b) combinations of circuits and computer program product(s) comprising software and / or firmware instructions stored on one or more computer readable memories that work together to cause an apparatus to perform one or more functions described herein; and (c) circuits, such as, for example, 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. This definition of ‘circuitry’ applies to all uses of this term herein, including in any claims. As a further example, as used herein, the term ‘circuitry’ also includes an implementation comprising one or more processors and / or portion(s) thereof and accompanying software and / or firmware. As another example, the term ‘circuitry’ as used herein also includes, for example, 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, other network device (such as a core network apparatus), field programmable gate array, and / or other computing device.

[0035] The term “comprising” means including but not limited to and should be interpreted in the manner it is typically used in the patent context. Use of broader terms such as comprises, includes, and having should be understood to provide support for narrower terms such as consisting of, consisting essentially of, and comprised substantially of. Furthermore, to the extent that the terms “includes” and “including,” and variants thereof are used in either the detailed description or the claims, these terms are intended to be inclusive in a manner similar to the term “comprising.”

[0036] The phrases “in one embodiment,” “according to one embodiment,” “in some embodiments,” “in various embodiments”, and the like generally refer to the fact that the particular feature, structure, or characteristic following the phrase may be included in at least one embodiment of the present disclosure, but not necessarily all embodiments of the present disclosure. Thus, the particular feature, structure, or characteristic may be included in more than one embodiment of the present disclosure such that these phrases do not necessarily refer to the same embodiment.

[0037] As used herein, the terms “example,” “exemplary,” and the like are used to mean “serving as an example, instance, or illustration.” Any implementation, aspect, or design described herein as “example” or “exemplary” is not necessarily to be construed as preferredor advantageous over other implementations, aspects, or designs. Rather, use of the terms “example,” “exemplary,” and the like are intended to present concepts in a concrete fashion.

[0038] If the specification states a component or feature “may,” “can,” “could,” “should,” “would,” “preferably,” “possibly,” “typically,” “optionally,” “for example,” “often,” or “might” (or other such language) be included or have a characteristic, that particular component or feature is not required to be included or to have the characteristic. Such component or feature may be optionally included in some embodiments, or it may be excluded.

[0039] As used herein, the term “computer-readable medium” refers to signal, non- transitory computer-readable medium and the like. The term ‘non-transitory computer- readable medium’ refers to non-transitory storage hardware, non-transitory storage device or non-transitory computer system memory that may be accessed by a controller, a microcontroller, a computational system or a module of a computational system to encode thereon computer-executable instructions or software programs. A non-transitory “computer-readable medium” may be accessed by a computational system or a module of a computational system to retrieve and / or execute the computer-executable instructions or software programs encoded on the medium. Examples of non-transitory computer-readable media may include, but are not limited to, one or more types of hardware memory, non- transitory tangible media (for example, one or more magnetic storage disks, one or more optical disks, one or more USB flash drives), computer system memory or random-access memory (such as, DRAM, SRAM, EDO RAM), and the like.

[0040] As illustrated in FIG. 1, a communication network 100 is provided in accordance with various embodiments of the present disclosure. In some embodiments, the communication network 100 is in communication with a plurality of user equipment (UE) 110. By way of example, the network 100 may be deployed within a radio access architecture based on long term evolution advanced (LTE Advanced, LTE-A) and / or new radio (NR, 5G). However, the system may be deployed in other network architectures including within other communication networks including, for example, other communication networks developed in the future, e.g., sixth generation (6G) networks, as well as any of a number of existing networks including a universal mobile telecommunications system (UMTS) radio access network (UTRAN, E-UTRAN or NG-RAN), wireless local area network (WLAN or WiFi), worldwide interoperability for microwave access (WiMAX), Bluetooth®, personal communications services (PCS), ZigBee®, wideband code division multiple access (WCDMA), systems using ultra-wideband (UWB) technology, sensor networks, mobile ad-hoc networks (MANETs) and Internet Protocol multimedia subsystems (IMS) or any combination thereof.

[0041] The UE 110 may be any type of user terminal, terminal device, etc. to which resources on the air interface are allocated and assigned. For example, the UE 110 may be a portable computing device such as a wireless mobile communication device including, but not limited to, the following types of devices: a mobile station (mobile phone), smartphone, personal digital assistant (PDA), handset, device using a wireless modem (alarm or measurement device, etc.), laptop and / or touch screen computer, tablet, game console, notebook, and multimedia device. The user equipment may also be called a subscriber unit, mobile station, remote terminal, access terminal, user terminal or user equipment (UE) just to mention but a few names or apparatuses.

[0042] The network 100 may include a plurality of network devices, such as a variety of network nodes 120 that serve one or more UEs 110. In some embodiments, the network node 120 includes a current serving cell 130 that is currently providing network services to one or more UEs 120. The current serving cell shown in the figures and described herein may also be referred to as a distributed unit, serving distributed unit, source unit, and / or the like. The current serving cells described herein may also be referred to as source cells. In some embodiments, the network node includes one or more candidate cells that are not currently serving the UE 110 and embody a candidate target for serving one or more UE 110 (also referred to herein as a “candidate target cell”). For example, the network node 120 may include candidate cells 140a, 140b that are not currently serving the UE 110. In various embodiments, the present disclosure provides improved systems and techniques for enabling the UE 110 to determine whether a control message from the network node 120 for activation or deactivation of SP CSI-RS resource sets applies for a serving cell 130 or a candidate cell 140a, 140b for LTM. In various embodiments, the network node 120 generates and provisions (and the UE 110 receives) a control message that encodes one or more fields indicative of when the control message applies to a candidate cell 140a, 140b.

[0043] The network node 120 and UE 110 may be configured to perform LTM. In various embodiments, LTM refers to a cell switch procedure in which the serving cell of the UE 110 (e.g., a primary cell (PCell) or secondary cell (SCell)) is switched by the network 100 by sending an LTM cell switch command. In some embodiments, the LTM cell switch command embodies one or more control messages that are generated by the network node 120 and provisioned to the UE 110. In some embodiments, a control message embodies a medium access control element (MAC CE). For example, an LTM switch command may bedelivered by MAC signaling using a MAC CE. In various embodiments, an LTM cell switch decision is based on measurements (e.g., LI measurements) that are performed and reported by the UE 110 to the network node 120. For example, the UE 110 may provision an LI measurement report to the network node 120 to cause the network 120 (e.g., or serving cell 130 thereof) to generate an LTM cell switch decision based at least in part on the LI measurement report. In some embodiments, measurements and reporting are based on a respective LTM candidate cell configuration provided by the network node for one or more candidate cells 140a, 140b. In various embodiments, a candidate cell may refer to one or more neighboring cells of a current serving cell. Additionally, in some embodiments, a candidate cell may refer to a current serving cell of a UE 110 (e.g., SCells and / or the like).

[0044] In legacy approaches, LTM measurements on a neighboring candidate cell 140a, 140b are performed using SSBs transmitted by the candidate cell for which the SSB configuration is provided to the UE 110. In some embodiments, before the cell switch, the network node 120 optionally activates one or more TCI states for one or more candidate cells 140a, 140b. In some embodiments, in response to activation of a candidate cell TCI state, the UE 110 tracks the time and / or frequency synchronization of the corresponding candidate cell using the reference signals associated with the one or more activated TCI states. In some embodiments, the UE 110 performs early UL synchronization before the cell switch (e.g., if requested or commanded to do so by the network node 110).

[0045] In an example signaling procedure for legacy SSB-based cell switching 700 shown in FIG. 7, the UE 110 may send a MeasurementReport message (e.g., a layer 3 measurement report) to the network node 120 (signal 701). The network node 120 may decide to configure LTM and initiate LTM preparation. The network node 120 may transmit an RRCReconfiguration message to the UE 110 including the SSB LTM candidate configurations (signal 702). The UE 110 may store the SSB LTM candidate configurations and transmit an RRCReconfigurationComplete message to the network node 120 (signal 703). The UE 110 may perform DL synchronization and UL synchronization with one or more candidate cells before receiving the cell switch command (operations 704a, 704b). The UE 110 may perform early timing advance (TA) acquisition with the one or more candidate cells as requested by the network node 110 before receiving the cell switch command. For example, the UE 110 may receive a physical downlink control channel (PDCCH) order from a serving cell that triggers contention free random access (CFRA), following which the UE 110 may send a preamble towards the indicated candidate cell. To minimize the data interruption of the serving cell due to CFRA towards one or more candidate cells, the UE110 does not receive random access response from the network node 110 for the purpose of TA value acquisition. Instead, the TA value of the candidate cell may be indicated in the cell switch command (e.g., a MAC CE). The UE 110 may not maintain the TA timer for the candidate cell. Instead, the UE 110 may rely on network implementation to guarantee the TA validity.

[0046] Continuing the scenario, the UE 110 may perform SSB-based LI measurements on the one or more configured candidate cells and transmit SSB-based LI measurement reports to the network node 120 (signal 705). The network node 120 may decide to execute cell switch to a target cell and transmits a cell switch command (e.g., MAC CE) triggering cell switch by including the candidate configuration index of the target cell (signal 706). The UE 110 may switch to the target cell and apply the configuration indicated by the candidate configuration index. If the UE 110 does not have valid TA of the target cell, the UE 110 may perform a random access channel (RACH) procedure towards the target cell (operation 707). The UE 110 may complete the LTM cell switch procedure by sending RRCReconfigurationComplete message to the target cell. If the UE 110 has performed a RACH procedure per operation 707, the UE 110 may consider that LTM cell switch execution is successfully completed when the RACH procedure is successfully completed. For RACH-less LTM, the UE 110 may consider that LTM cell switch execution is successfully completed when the UE 110 determines that the network node 120 has successfully received its first UL data.

[0047] As described herein, the above SSB measurement-based scenario may demonstrate drawbacks as compared to CSLRS measurements due to the narrower bandwidth, longer periodicity, and wider beams required to generate the SSB measurements. For example, CSL RS measurements may support the use of narrower beams over larger bandwidth and shorter periodicity as compared to SSB measurements. In doing so, the CSLRS-based approach may achieve greater time and frequency synchronization with the target cell as compared to SSB- based approaches. However, existing signaling techniques lack means for indicating to the UE 110 whether a control message for activation and / or deactivation of one or more CSL RSs or CSLRS resource sets applies to a current serving cell or a candidate cell. As a result, such techniques may be unable to instruct the UE 110 as to activation or deactivation of one or more SP CSLRSs or one of more SP CSLRS resource sets and / or the like for various candidate cells. In various embodiments, the present methods, apparatuses, and computer program products overcome this challenge, and others, by introducing novel signaling techniques for indicating whether a control message for SP CSLRS resource set activationand deactivation is associated with a serving cell or candidate cell. In various embodiments, a UE 110 and a network node 120 may be configured to perform CSI-RS-based LTM as shown in FIGS. 4A-B and described herein, which may include the UE 110 performing the process 500 and the network node 120 performing the process 600 as shown in FIGS. 5 and 6, respectively, and described herein.

[0048] In various embodiments, for LTM, information about measurement resources (e.g., SSBs in existing approaches or CSLRSs per the present disclosure) from LTM candidate cells are provided to the UE so that UE may generate corresponding measurements. For example, information about SSBs, CSLRSs, and / or the like may be provided to the UE to enable the UE to generate SSB measurements, CSLRS measurements, and / or the like on one or more candidate cells. In some embodiments, the UE is also configured with LI measurement reporting configuration where the UE can report the measurements. In various embodiments, for LTM, periodic and semi-persistent report on PUCCH, semi-persistent report on PUSCH, and aperiodic report on PUSCH are supported. In some embodiments, the configuration of CSLRSs, CSLRS resource sets for a candidate cell (e.g., SP resource sets for one or more CSLRSs), and / or the like are provided under the LTM candidate information element of the candidate cell. Table 1 shows an example of LTM candidate information element including potential components related to CSLRS configuration relevant for the present disclosure, which are indicated in bold and underlining. Table 2 provides descriptions of the various candidate fields of the example modified LTM candidate information element shown in Table 1. Table 3 provides descriptions of the various SSB configuration fields of the example modified LTM candidate information element shown in Table 1.Table 1. Modified LTM Candidate Information Element.Table 2. Candidate Field Descriptions.Table 3. SSB Configuration Field Descriptions.

[0049] FIG. 2 shows example apparatuses 200a, 200b according to one embodiment. The apparatuses 200a, 200b may be embodiments of network devices or may be embodied by or otherwise associated with one or more network devices. For example, the apparatus 200amay be embodied by a UE 110 and the apparatus 200b may be embodied as a network node 120, or one or more elements thereof (e.g., serving cell, centralized unit, candidate cell, and / or the like).

[0050] Regardless of the device that embodies the apparatus 200a (or 200b), the apparatus may include processor 202a (202b), memory 204a (204b), and network interface 206a (206b). The apparatuses 200a, 200b may be configured to execute the operations described herein. For example, the apparatus 200a may be configured to perform the process 500 shown in FIG. 5. As another example, the apparatus 200b may be configured to perform the process 600 show in FIG. 6. Although these components are described with respect to the performance of various functions, it should be understood that the particular implementations necessarily include the use of particular hardware. It should also be understood that certain of these components may include similar or common hardware. For example, two sets of circuitries may both leverage use of the same processor, network interface, storage medium, or the like to perform their associated functions, such that duplicate hardware is not required for each set of circuitries. The proceeding description of the processor 202a, 204a, and network interface 206a of the apparatus 200a may apply to similarly named elements of the apparatus 200b (e.g., processor 202b, 204b, and network interface 206b).

[0051] In some embodiments, the processor 202a (and / or co-processor or any other processing circuitry assisting or otherwise associated with the processor) may be in communication with the memory 204a via a bus for passing information among components of the apparatus. The memory 204a is non-transitory and may include, for example, one or more volatile and / or non-volatile memories. In other words, for example, the memory 204a may be an electronic storage device (e.g., a non-transitory computer-readable storage medium). The memory 204a may be configured to store information, data, content, applications, instructions, or the like for enabling the apparatus to carry out various functions in accordance with an example embodiment disclosed herein. For example, the memory 204a may store identifiers for one or more serving cells, candidate cells, CSI-RS resource sets (e.g., SP resource sets and / or the like), TCI states, bandwidth parts (BWPs), logic channel identifiers, and / or the like. As another example, the memory 204a may store CSI- RS resource sets, control messages, and / or the like.

[0052] The processor 202a may be embodied in a number of different ways and may, for example, include one or more processing devices configured to perform independently. In some non-limiting embodiments, the processor 202a may include one or more processorsconfigured in tandem via a bus to enable independent execution of instructions, pipelining, and / or multithreading. The use of the term “processor” may be understood to include a single core processor, a multi-core processor, multiple processors internal to the apparatus, and / or remote or “cloud” processors.

[0053] In some embodiments, the processor 202a may be configured to execute instructions stored in the memory 204a and / or circuitry otherwise accessible to the processor 202a. In some embodiments, the processor 202a may be configured to execute hard-coded functionalities. As such, whether configured by hardware or software methods, or by a combination thereof, the processor 202a may represent an entity (e.g., physically embodied in circuitry) capable of performing operations according to an embodiment disclosed herein while configured accordingly. Alternatively, as another example, when the processor 202a is embodied as an executor of software instructions, the instructions may specifically configure the processor 202a to perform the algorithms and / or operations described herein when the instructions are executed.

[0054] In some embodiments, the apparatus 200a may optionally include input / output circuitry that may, in turn, be in communication with processor 202a to provide output to a user and / or other entity and, in some embodiments, to receive an indication of an input. The input / output circuitry may comprise a user interface and may include a display, and may comprise a web user interface, a mobile application, a query-initiating computing device, a kiosk, or the like. In some embodiments, the input / output circuitry may also include a keyboard, a mouse, a joystick, a touch screen, touch areas, soft keys, a microphone, a speaker, or other input / output mechanisms. The processor and / or user interface circuitry comprising the processor may be configured to control one or more functions of one or more user interface elements through computer program instructions (e.g., software and / or firmware) stored on a memory accessible to the processor (e.g., memory 204a, and / or the like).

[0055] The network interface 206a may be any means such as a device or circuitry embodied in either hardware or a combination of hardware and software that is configured to receive and / or transmit data from / to a network and / or any other device, circuitry, or module in communication with the apparatus 200a. In this regard, the network interface 206a may include, for example, a network interface for enabling communications with a wired or wireless communication network, such as the application function (AF), multicast and broadcast service function (MBSF), multicast and broadcast user plane function (MB-UPF), and / or multicast and broadcast session management function (MB-SMF). For example, thenetwork interface 206a may include one or more network interface cards, antennae, buses, switches, routers, modems, and supporting hardware and / or software, or any other device suitable for enabling communications via a network. Additionally, or alternatively, the network interface 206a may include the circuitry for interacting with the antenna / antennae to cause transmission of signals via the antenna / antennae or to handle receipt of signals received via the antenna / antennae.

[0056] FIGS. 3A-3B illustrate, respectively, a legacy control message 300A and an example control message 300B for improved CSI-RS-based LTM in accordance with the present disclosure.

[0057] In some embodiments, a network node activates and deactivates one or more configured SP CSI-RS resource sets, CSI-interference measurement (IM) resource sets, and / or the like by generating and sending one or more control messages to a UE. In some embodiments, if the MAC entity (e.g., UE) receives a control message indicative activation and / or deactivation of one or more SP CSI-RS resource sets, CSI-IM resource sets, and / or the like for a current serving cell, the MAC entity indicates to lower layers information associated with the control message (e.g., resource set identifiers and / or the like).

[0058] In various embodiments, a control message 300 A, 300B identifies one or more CSI- RSs or more specifically one or more CSI-RS resource sets for activation or deactivation. For example, a control message may identify one or more SP CSI-RS resource sets, one or more CSI-interference measurement (IM) resource sets, and / or the like for activation or deactivation. The control message may embody a MAC CE, and / or the like. In some embodiments, the configured SP CSI-RS resource sets CSI-IM resource sets, and / or the like are initially deactivated upon configuration (or reconfiguration) by upper layers and after reconfiguration with synchronization (e.g., UL synchronization, DL synchronization, and / or the like).

[0059] In some embodiments, the control messages 300 A, 300B embody multi -field data objects of variable size. For example, the control messages 300A, 300B may embody multifield MAC CEs. In some embodiments, a control message comprises a sub-header that identifies activation and deactivation for one or more SP CSI-RS resource sets, CSI-IM resource sets, and / or the like.

[0060] In various embodiments, the control messages 300 A, 300B include, respectively, a first field 301, second field 303, third field 305, fourth field 307, fifth field 309, and / or the like. In some embodiments, the first field 301 embodies an activation / deactivation (A / D) field. In some embodiments, the first field 301 indicates whether to activate or deactivateone or more SP CSI-RS resource sets, CSI-IM resource sets, and / or the like that are further indicated by the control message. For example, in a first value (e.g., 0), the first field 301 may indicate that one or more indicated SP CSI-RS resource sets, CSI-IM resource sets, and / or the like are activated. In a second value (e.g., 1), the first field 301 may indicate that that one or more indicated SP CSI-RS resource sets, CSI-IM resource sets, and / or the like are deactivated. As used herein, “deactivation” refers to deactivation of a currently activated resource. For example, a control message for deactivation of an SP CSI-RS resource set may refer to deactivation of a currently activated SPI CSI-RS resource set. In some embodiments, the legacy control message 300 A includes a serving cell identifier bit field 302 configured to indicate an identifier of a current serving cell. Further, the legacy control message 300A lacks a field for indicating an identifier of a candidate cell. As a result, the legacy control message 300 A may be unable to indicate whether activation or deactivation of one or more SP CSI-RS resource sets, CSI-IM resource sets, and / or the like applies to a serving cell or an LTM candidate cell.

[0061] To address this deficiency, the control message 300B introduces a cell identifier bit field 304 and a field 306. In various embodiments, the cell identifier bit field 304 is configured to indicate an identifier for a current serving cell or an identifier for a candidate cell. For example, the cell identifier bit field 304 may comprise a bitstring embodying an identifier for a serving cell or an identifier for a candidate cell. In some embodiments, the field 306 (e.g., “S / L” field or “L” field) is configured to indicate whether the identifier of cell identifier bit field 304 comprises an identifier for a serving cell or an LTM candidate cell. In other words, the field 306 (e.g., “S / L” field or “L” field) indicates whether or not the control message applies to SP CSI-RS / CSI-IM Resource Set Activation / Deactivation for LTM. The field 306 may be configurable between first value (e.g., 0) and a second value (e.g., 1). The cell identifier bit field 304 may comprise a bit length of five bits. The field 306 may comprise a bit length of one bit.

[0062] In various embodiments, when the field 306 comprises a first value (e.g., 0), the field 306 indicates to the UE that the cell identifier bit field 304 comprises an identifier of a current serving cell. In some embodiments, in a second value (e.g., 1), the field 306 indicates to the UE that the cell identifier bit field 304 comprises an identifier of a candidate cell. In doing so, the control message 300B may indicate to the UE whether activation or deactivation of one or more SP CSI-RS resource sets, CSI-IM resource sets, and / or the like applies to a serving cell or an LTM candidate cell. As a result, the control message 300B may enabletriggering of CSI-RS measurement and reporting by the UE such that CSI-RS-based LTM may be performed.

[0063] In some embodiments, the value of the field 306 may be further conditioned the presence of additional configurations. For example, if no LTM CSI report configuration (e.g., Itm-CSI-ReportConfigToAddModLisf) is provided to the UE, R field may be present instead (e.g., set to 0). In some embodiment, if there is no SP CSI-RS resource configuration from candidate cells is provided to the UE, R field may be present instead (e.g., set to 0).

[0064] In some embodiments, the second field 303 comprises a bitstring indicative of a respective identifier for one or more BWPs. The second field may comprise a bit length of two bits. In some embodiments the second field 303 indicates a DL BWP for which the control message applies as the codepoint of a downlink control information (DCI) BWP indicator field. In some embodiments, when the field 306 is configured to a second value (e.g., 1), the field 306 indicates that the second field 303 (e.g., “BWP field”) is not encoded, or ignored by the UE or set to 0. In some embodiments, when the field 306 is configured to a second value (e.g., 1), the field 306 indicates that the second field 303 (e.g., “BWP field”) is not encoded, or ignored by the UE, and the BWP for which the activation or deactivation applies is the current active BWP (e.g., current BWP identifier). Alternatively, in some embodiments, when the field 306 is configured to the second value, the field 306 indicates that the bitstring of the second field 303 refers to the current serving cell DL BWP ID.

[0065] In some embodiments, the third field 305 (e.g., “IM field”) indicates the presence of an octet containing a SP CSLIM resource set ID field (e.g., presence of the fifth field 309). In some embodiments, the third field 305 is configurable between a first value (e.g., 0) and a second value (e.g., 1). In some embodiments, if the third field 305 is set to a second value (e.g., 1), an octet containing SP CSLIM resource set ID field is present (e.g., encoded). In some embodiments, if the third field 305 is set to a first value (e.g., 0), an octet containing SP CSLIM resource set ID field is not present. Additionally, or alternatively, when the field306 is configured to the second value (e.g., 1), the field 306 indicates that the third field 305 is set to zero or not encoded or ignored by the UE. In some embodiments, the fourth field307 comprises a bitstring indicative of a respective identifier for one or more SP CSLRS resource sets to be activated or deactivated (e.g., based on the value of the first field 301). For example, the fourth field 307 may include an index of a non-zero-power (NZP)-CSLRS- ResourceSet containing Semi Persistent NZP CSLRS resources, indicating the SP-NZP- CSLRS resource set, which shall be activated or deactivated by the UE based on the control message. In various embodiments, when the field 306 is configured to a second value (e.g.,1), the field 306 indicates that the bitstring of the fourth field 307 comprises a bitstring indicative of an SP CSI-RS resource set identifier for the indicated candidate cell identifier of the cell identifier bit field 304. In some embodiments, the fourth field 307 comprises a bit length of six bits.

[0066] In some embodiments, the fifth field 309 comprises a bitstring indicative of a respective identifier for one or more IM resource sets to be activated or deactivated (e.g., based on the value of the first field 301). The fifth field 309 may embody a SP CSI-IM resource set ID field. In some embodiments, when the field 306 is configured to a second value (e.g., 1), the field 306 indicates that the third field 305 and the fifth field 309 are not encoded or are ignored by the UE. Alternatively, in some embodiments, when the field 306 is configured to the second value, the field 306 indicates that the third field 305 is set to zero. Additionally, or alternatively, in some embodiments, when the field 306 and third field 305 are configured to the second value, the field 306 and third field 305 indicate that the bitstring of the fifth field 309 contains an index of CSI-IM-ResourceSet (e.g., CSI-IM resource set) for the indicated candidate cell identifier of the cell identifier bit field 304. In some embodiments, the fifth field 309 comprises a bit length of six bits.

[0067] In some embodiments, the sixth and seventh fields 311, 313 embody TCI fields and comprise bitstrings indicative of respective identifiers for one or more TCI states. In some embodiments, if the first field 301 is configured to the second value (e.g., 1), the first field 301 indicates that octets containing TCI state fields (e.g., sixth field 311, seventh field 313, and / or the like) are not present. In some embodiments, when present, the sixth field 311, seventh field 313, and / or the like includes a respective TCI state identifier. In some embodiments, a TCI state identifier is used as the quasi-co-located (QCL) source for a respective resource within the SP-NZP-CSI-RS resource set indicated by the fourth field 307. In some embodiments, the sixth field 311 indicates a TCI state identifier for a first resource in the resource set, the seventh field 313 indicates TCI state identifier for an n-th resource in the resource set, and further field may include additional TCI state identifiers for additional resources in the resource set.

[0068] In some embodiments, when the field 301 is configured to a first value (e.g., 0), the field 301 indicates that the octets containing TCI state identifier fields are not present (e.g., sixth field 311, seventh field 313, and / or the like, are not present). In some embodiments, when the when the field 301 is configured to a second value (e.g., 1) and when the field 306 is configured to the second value (e.g., 1), the field 306 indicates that the respective bitstrings of the sixth field 311, seventh field 313, and / or the like containing TCI state information(e.g., TCI state identifier) comprise a TCI state identifier in the CandidateTCI-State (e.g., TCI state identified by TCI-Stateld in Itm-DL-OrJointTCI-StateToAddModList) of the candidate cell indicated by the cell identifier bit field 304. In some embodiments, the sixth field 313, seventh field 313, and / or the like comprise a bit length of seven bits.

[0069] In various embodiments, by introduction of the fields 304, 306, the control message 300B improves over the legacy control message 300 A in that activation and deactivation for CSI-RS resource sets, TCI states, and / or the like may be indicated as applying to a serving cell or a candidate cell. In doing so, the control message 300B enables LI measurement and reporting of candidate cell CSLRSs for LTM execution. As a result, LTM cell switching may be enhanced using CSI-RS LI measurements in place of (or in addition to) SSB-based measurements.

[0070] Alternatively, or additionally, in some embodiments, a sub-header of the control message 300B includes a logical channel identifier (LCID), extended LCID (eLCID), and / or the like that indicates the control message is for activation or deactivation of SP CSI-RSs for a candidate cell. For example, the control message 300B may include a unique LCID, eLCID, and / or the like that indicates the control message 300B is for activation or deactivation of SP CSI-RSs and / or associated resource sets for an LTM candidate cell. In various embodiments, the sub-header of the control message may include an LCID value different than values used to indicate activation and / or deactivation of legacy SP CSI-RSs of serving cells.

[0071] In some embodiments, when the control message 300B is for activation and / or deactivation of SP CSI-RSs and / or associated resource sets for a candidate cell, the control message 300B includes a field indicative that a cell identifier of the control message encodes a candidate cell identifier. In such embodiments, the control message 300B may include an SP CSI-RS resource set identifier field including an index of an NZP-CSLRS resource set for the indicated candidate cell identifier. Further, in such embodiments, an IM field and SP CSLIM resource set identifier field may not be encoded in the control message 300B or may be ignored by the UE. Alternatively, when the IM field is present and configured to a second value (e.g., 1), the IM field may indicate that the SP CSLIM resource set identifier field contains an index of CSLIM-ResourceSet for the indicated candidate cell identifier. In such contexts, the control message 300B may include a TCI state identifier field including TCI state information, such as a TCI state identifier in the CandidateTCI-State (TCI state identified by TCI-Stateld in Itm-DL-OrJointTCI-StateToAddModList) of the candidate cell. In such embodiments, a BWP field may not be encoded in the control message 300B or maybe ignored by the UE such that the BWP for which the indicated activation or deactivation applies is the current active BWP (e.g., BWP identifier). Alternatively, the UE may interpret the BWP field as referring to the serving cell DL BWP ID.

[0072] Referring now to FIGS. 4 A, 4B shown are example signal diagrams 400 A, 400B for CSI-RS-based LTM. In some embodiments, the UE 110 provisions a MeasurementReport message to the serving cell 130 of the network node 120 (signal 401). The serving cell 130 may provision the MeasurementReport message to a centralized unit 430 of the network node 120. The network node 120 may decide to configure LTM and initiate LTM preparation. The network node 120 may transmit an RRCReconfiguration message to the UE 110 including data for one or more LTM candidate configurations (signal 402). In various embodiments, a respective LTM candidate configuration includes respective configurations of one or more candidate SP CSLRS resource sets.

[0073] In some embodiments, the UE 110 stores the LTM candidate configurations (including configurations of SP CSLRS resource sets) and transmits an RRCReconfigurationComplete message to the serving cell 130, which may provision the message to the centralized unit 430 (signal 403). The UE 110 may perform DL synchronization and UL synchronization with one or more candidate cells before receiving the cell switch command (operations 404a, 404b). The UE 110 may perform early timing advance (TA) acquisition with the one or more candidate cells as requested by the network node 110 before receiving the cell switch command.

[0074] As shown in FIG. 4B, the UE 110 may provision to the network node 120 an LI measurement report including measurements on one or more SSBs, periodic CSLRSs, and / or the like (signal 405). The network node 120 may provision to the UE 110 a control message for activation and / or deactivation of one or more SP CSLRS resource sets of one or more candidate cells 140 (signal 406). The network node 120 may determine to activate a SP CSL RS of a candidate cell based on UE measurements. For example, based on measurement reports from the UE containing measurements of SSBs of candidate cell(s) or / and periodic CSLRSs, the network node 120 may determine to trigger additional measurements and reporting using SP CSLRSs. For example, the serving cell 130 may provision a control message to the UE 110. The control message may embody a control message 300B as shown in FIG. 3B and described herein. In some embodiments, the UE 110 generate LI measurements on one or more CS-RSIs of one or more configured candidate cells 140 based on the control message. In some embodiments, the information includes an identifier of a cell and an indication (e.g., one or more bits) indicating whether a cell is a serving cell 130or a candidate cell 140 for LTM procedure for the UE 110. In some embodiments, the indication includes a logical channel identifier (LCI). In some embodiments, the information includes one or more indications of resource configurations of a respective CSI-RS. In some embodiments, the control message indicates that the cell is a candidate cell 140 and causes the UE 110 to ignore a bit field of the control message that is associated with resource configuration for IM.

[0075] In some embodiments, the control message includes an indication indicating whether a bit field associated with resource configuration for IM is present or absent. In some embodiments, the control message includes respective TCI state information for an LTM candidate cell. In some embodiments, the control message indicates that the cell is a candidate cell 140 and causes the UE 110 to ignore a bit field associated with DL BWP. Additionally, in some embodiments, the control message causes the UE to apply a current configured DL BWP in generating LI measurements. Alternatively, or additionally, in some embodiments, the control message causes the UE 110 to apply primary cell (Pcell) DL BWP.

[0076] In some embodiments, the network node 120 provisions to the UE 110 a second control message triggering reporting on the one or more activated candidate CSI RSs (signal 407). For example, the serving cell 130 may provision a second control message (e.g., second MAC CEs) to the UE 110 to trigger reporting on one or more activated candidate SP CSL RSs). The UE 110 may generate LI measurements on one or more activated candidate CSL RSs. In various embodiments, the UE 110 generates and provisions an LI measurement report to the network node 120 based on the second control message (signal 408). For example, the UE 110 may provision to the serving cell 130 an LI measurement report including measurements on one or more activated SP CSLRSs. Based on the LI measurement report, the network node 120 may determine to execute cell switch to a target candidate cell 140 and transmit a cell switch command (e.g., control message, such as a MAC CE) triggering cell switch by including the candidate configuration index of the target cell in the cell switch command (signal 409). The UE 110 may switch to the target cell and apply the configuration indicated by the candidate configuration index. If the UE 110 does not have valid TA of the target candidate cell 140, the UE 110 may perform a random access channel (RACH) procedure towards the target candidate cell 140 (operation 410). The UE 110 may complete the LTM cell switch procedure by sending RRCReconfigurationComplete message to the target cell. If the UE 110 has performed a RACH procedure per operation 410, the UE 110 may consider that LTM cell switch execution is successfully completed when the RACH procedure is successfully completed.For RACH-less LTM, the UE 110 may consider that LTM cell switch execution is successfully completed when the UE 110 determines that the network node 120 has successfully received its first UL data.

[0077] Referring now to FIG 5., shown is an example flowchart of a CSI-RS resource signaling process 500. The process 500, or blocks / steps / operations thereof, may be performed by one or more apparatuses 200a as shown in FIG. 2 and described herein. In various embodiments, the apparatus performing the process 500 embodies a UE 110.

[0078] In some embodiments, at block 503, the apparatus performing the process 500 includes means, such as the processor 202a, the memory 204a, the network interface 206a, or the like, for receiving configuration data for one or more CSI-RS signals of one or more cells of a network node. For example, the apparatus 200a may receive from a network node configuration data for one or more CSI-RSs of one or more cells of the network node. In some embodiments, the configuration data indicates one or more SP CSI-RS resource sets for a respective CSI-RS. In some embodiments, a respective SP CSI-RS resource set includes an SP-nonzero power (NZP) CSI RS resource set associated with the corresponding cell.

[0079] In some embodiments, at block 506, the apparatus performing the process 500 includes means, such as the processor 202a, the memory 204a, the network interface 206a, or the like, for receiving a control message indicative of activation or deactivation of one or more SP CSI-RS resource set of the one or more cells. In various embodiments, the control message further indicates whether a respective cell is a serving cell or a candidate cell, such as an LTM candidate cell. For example, the apparatus 200a may receive said control message from a network node comprising a current serving cell and one or more candidate cells (e.g., LTM candidate cells, and / or the like). In some embodiments, the control message includes one or more fields. The control message may embody a control message 300B as shown in FIG. 3 and described herein. In some embodiments, the control message comprises a MAC CE.

[0080] In some embodiments, the control message includes a cell identifier bit field comprising a respective identifier for the one or more cells. In some embodiments, the control message includes a second bit field configurable between a first value (e.g., 0) and a second value (e.g., 1). In some embodiments, in the first value, the second bit field indicates the cell is a serving cell. In some embodiments, in the second value, the second bit field indicates the cell is a candidate cell, such as an LTM candidate cell. In some embodiments, the control message includes a third bit field including a bit string. In some embodiments, inthe second value, the second bit field further indicates that the bitstring of the third bit field comprises a respective identifier for one or more SP CSI-RS resource sets.

[0081] In some embodiments, the control message further includes an A / D field configurable between the first value and the second value. In some embodiments, in the first value, the A / D field indicates that the respective SP CSI-RS resource set is activated for the corresponding cell. In some embodiments, in the second value, the A / D bit field indicates that the respective SP CSI-RS resource set is deactivated for the respective cell. In some embodiments, the control message includes an IM field. In some embodiments, in the second value, the second bit field indicates that the IM field is set to zero for a cell. In some embodiments, the control message includes an SP CSI-RS identifier field (e.g., the third field or another field). In some embodiments, in the second value, the second bit field further indicates that the IM field and the SP CSI-RS resource set identifier field are at least one of set to zero for the at least one cell, not encoded, or to be ignored.

[0082] In some embodiments, the IM field is configurable between the first value and the second value. In some embodiments, in the second value, the second bit field and the IM field indicate that the bitstring of the SP RSI-CSI resource set identifier field comprises an index of a SP CSI-IM resource set associated with the identifier for the cell. In some embodiments, the control message comprises one or more TCI fields comprising a respective bitstring. In some embodiments, in the second value, the second bit field indicates that the respective bitstring of a TCI field comprises a TCI state identifier for the identified cell.

[0083] In some embodiments, the control message comprises an additional field associated with BWP information. In some embodiments, in the second value, the second bit field indicates that the third field is not encoded or to be ignored in the generation of LI measurements for the one or more CSLRSs of the cell. Alternatively, in some embodiments, in the second value the second bit field indicates that the activation or deactivation of a respective SP CSI-RS resource set applies to an active BWP for the current serving cell. Alternatively, in some embodiments, in the second value the second bit field indicates that the activation or deactivation of the at least one SP CSI-RS resource set applies to a current configured BWP for the identified.

[0084] In some embodiments, in the second value, the second bit field indicates that a bitstring of the BWP-associated field includes a DL BWP identifier for the current serving cell 130 of the UE 110. Alternatively, in the second value, the second bit field indicates that the additional field is to be ignored in generation of LI measurements for the identified cell.

[0085] In some embodiments, at block 509, the apparatus performing the process 500 optionally includes means, such as the processor 202a, the memory 204a, the network interface 206a, or the like, for receiving a second control message triggering reporting of LI measurements for one or more configured CSLRSs of the one or more cells. For example, the apparatus 200a may receive the second control message from the network node associated with the current serving cell. In some embodiments, the second control message embodies a second MAC CE.

[0086] In some embodiments, at block 512, the apparatus performing the process 500 optionally includes means, such as the processor 202a, the memory 204a, the network interface 206a, or the like, for generating one or more LI measurements on the one or more CSLRSs of a respective cell. For example, the apparatus 200a may generate one or more LI measurements on one or more configured CSLRSs of one or more LTM candidate cells of the network node. In some embodiments, where the control message of block 506 indicates that a field of the control message comprises a DL BWP identifier for the current serving cell, the apparatus performing the process 500 applies the active DL BWP for the current serving cell to the one or more LI measurements based at least in part on the DL BWP identifier. Alternatively, or additionally, in some embodiments, where the control message indicates that a BWP-associated field of the control message is to be ignored, the apparatus performing the process 500 applies a DL BWP of a primary cell of the network node to the one or more LI measurements.

[0087] In some embodiments, at block 515, the apparatus performing the process 500 optionally includes means, such as the processor 202a, the memory 204a, the network interface 206a, or the like, for provisioning one or more LI measurements to the network node. For example, the apparatus 200a may optionally provision a report comprising the one or more LI measurements to the network node. In some embodiments, at block 518, the apparatus performing the process 500 includes means, such as the processor 202a, the memory 204a, the network interface 206a, or the like, for receiving a command from the network node, where the command triggers cell switch on the apparatus. For example, the apparatus 200a may receive a third control message triggering cell switch from a current serving cell to an LTM candidate cell. In some embodiments, at block 521, the apparatus performing the process 500 includes means, such as the processor 202a, the memory 204a, the network interface 206a, or the like, for executing an LTM cell switch from a current serving cell to a candidate cell based at least in part on the command of block 518. For example, the apparatus 200a may execute an LTM cell switch from a current serving cell toan LTM candidate cell based at least in part on a third control message from the network node.

[0088] FIG. 6 shows an example flowchart of a CSI-RS resource signaling process 600. The process 600, or blocks / steps / operations thereof, may be performed by one or more apparatuses 200b as shown in FIG. 2 and described herein. In various embodiments, the apparatus performing the process 600 embodies a network node 120.

[0089] In some embodiments, at block 603, the apparatus performing the process 600 includes means, such as the processor 202b, the memory 204b, the network interface 206b, or the like, provisioning configuration data for one or more CSI-RS signals of one or more cells of a network node. For example, the apparatus 200b may provision configuration data to a UE. In some embodiments, block 603 may be performed similar to block 503 of the process 500, where the referenced network node is embodied by the apparatus 200b.

[0090] In some embodiments, at block 606, the apparatus performing the process 600 includes means, such as the processor 202b, the memory 204b, the network interface 206b, or the like, for provisioning a control message indicative of activation or deactivation of one or more SP CSI-RS resource set of the one or more cells. In various embodiments, the control message further indicates whether a respective cell is a serving cell or a candidate cell, such as an LTM candidate cell. For example, the apparatus 200b may provision said control message to a UE. In some embodiments, block 606 may be performed similar to block 506 of the process 500, where the referenced network node is embodied by the apparatus 200b.

[0091] In some embodiments, at block 609, the apparatus performing the process 600 includes means, such as the processor 202b, the memory 204b, the network interface 206b, or the like, for provisioning a second control message triggering reporting of LI measurements for one or more configured CSLRSs of the one or more cells. For example, the apparatus 200b may provision the second control message to the UE to cause the UE to generate one or more LI measurements. In some embodiments, block 606 may be performed similar to block 506 of the process 500, where the referenced network node is embodied by the apparatus 200b.

[0092] In some embodiments, at block 612, the apparatus performing the process 600 includes means, such as the processor 202b, the memory 204b, the network interface 206b, or the like, for receiving one or more LI measurements on the one or more CSLRSs of a respective candidate cell. For example, the apparatus 200b may receive from the UE a report comprising one or more LI measurements on the one or more CSLRSs of a respectivecandidate cell. In some embodiments, block 612 may be performed similar to block 515 of the process 500, where the referenced network node is embodied by the apparatus 200b.

[0093] In some embodiments, at block 615, the apparatus performing the process 600 includes means, such as the processor 202b, the memory 204b, the network interface 206b, or the like, for provisioning a command to the UE, where the command triggers cell switch on the UE and is based at least in part on the one or more LI measurements received at block 612. For example, the apparatus 200b may provision a third control message to the UE that triggers cell switch from a current serving cell to an LTM candidate cell. In some embodiments, block 612 may be performed similar to block 518 of the process 500, where the referenced network node is embodied by the apparatus 200b.

[0094] In some embodiments, at block 618, the apparatus performing the process 600 includes means, such as the processor 202b, the memory 204b, the network interface 206b, or the like, for executing an LTM cell switch from a current serving cell to a candidate cell. For example, in coordination with the UE, the apparatus 200b may execute an LTM cell switch from a current serving cell to an LTM candidate cell.

[0095] In various embodiments, the method, apparatus and computer program product of the present disclosure are provided for indicating whether a given control message for activation and deactivation of SP CSLRS is associated with a CSLRS of a current serving cell or a CSLRS of a LTM candidate cell. The method, apparatus, and computer program product provide improved solutions for enabling CSLRS-based LTM cell switching. In various embodiments, the method, apparatus, and computer program product introduce improved control message formats and signaling processes for indicating whether a control message is associated with a serving cell or candidate cell. In various embodiments, the method, apparatus, and computer program product improve telecommunication services by overcoming technical challenges associated with implementing CSLRS-based LTM, including a lack of signaling means for indicating activation or deactivation of CSLRS resource sets.

[0096] It will be understood that each block of the flowcharts and combination of blocks in the flowcharts show in the figures and described herein may be implemented by various means, such as hardware, firmware, processor, circuitry, and / or communication devices associated with execution of software including one or more program instructions. For example, one or more of the procedures or operations described above may be embodied by computer program instructions. In this regard, the computer program instructions which embody the procedures or operations described above may be stored by a memory 204a ormemory 204b of an apparatus (e.g., a UE or network node employing a disclosed embodiment and executed by a processor 202a or processor 202b). As will be appreciated, any such computer program instructions may be loaded onto a computer or other programmable apparatus (for example, hardware) to produce a machine, such that the resulting computer or other programmable apparatus implements the functions specified in the flowchart blocks. These computer program instructions may also be stored in a computer-readable memory that may direct a computer or other programmable apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture the execution of which implements the function specified the flowchart blocks. The computer program instructions may also be loaded onto a computer or other programmable apparatus to cause a series of operations to be performed on the computer or other programmable apparatus to produce a computer-implemented process such that the instructions which execute on the computer or other programmable apparatus provide operations for implementing the functions specified in the flowchart blocks.

[0097] Many modifications and other embodiments of the present disclosure set forth herein will come to mind to one skilled in the art to which these embodiments pertain having the benefit of the teachings presented in the foregoing descriptions and the associated drawings. Therefore, it is to be understood that the disclosure is not to be limited to the specific embodiments disclosed and that modifications and other embodiments are intended to be included within the scope of the appended claims. Moreover, although the foregoing descriptions and the associated drawings describe example embodiments in the context of certain example combinations of elements and / or functions, it should be appreciated that different combinations of elements and / or functions can be provided by alternative embodiments without departing from the scope of the appended claims. In this regard, for example, different combinations of elements and / or functions than those explicitly described above are also contemplated as can be set forth in some of the appended claims. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.

Claims

WE CLAIM:

1. 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 configuration data for at least one channel state information reference signal (CSI-RS) of at least one cell of a network node, wherein the configuration data indicates at least one semi-persistent (SP) CSI-RS resource set for a respective CSI-RS; and receive a control message associated with the at least one CSI-RS of the at least one cell of the network node, wherein at least one field of the control message indicates i) whether the at least one cell is a serving cell or a candidate cell, and ii) whether an activation or a deactivation of the at least one SP CSI-RS resource set applies to the at least one cell.

2. The apparatus of claim 1, wherein the instructions, when executed by the at least one processor, further cause the apparatus to: generate at least one layer-one (LI) measurement on the at least one CSI-RS of the at least one cell of based at least in part on the control message; and provision to the network node a report comprising the at least one LI measurement on the at least one CSI-RS for the at least one cell.

3. The apparatus of claim 2, wherein the instructions, when executed by the at least one processor, further cause the apparatus to: execute a lower-layer trigger mobility (LTM) cell switch from a current serving cell of the network node to a respective cell of the at least one cell in response to a second control message from the network node, wherein the second control message is based at least in part on the report.

4. The apparatus of claim 1, wherein: the at least one field comprises a cell identifier bit field comprising an identifier for the at least one cell.

5. The apparatus of claim 4, wherein: the at least one field further comprises a second bit field configurable between a first value and a second value; in the first value, the second bit field indicates the at least one cell is a serving cell; and in the second value, the second bit field indicates the at least one cell is a candidate cell.

6. The apparatus of claim 5, wherein: in the second value, the second bit field indicates that the candidate cell is an LTM candidate cell.

7. The apparatus of claim 5, wherein: the at least one field further comprises a third bit field comprising a bitstring; and in the second value, the second bit field further indicates that the bitstring of the third bit field comprises an identifier for a respective SP CSI-RS resource set of the at least one SP CSI-RS resource set of the respective CSI-RS of the at least one cell.

8. The apparatus of claim 7, wherein: the at least one field further comprises an activation / deactivation (A / D) field configurable between the first value and the second value; in the first value, the A / D field indicates that the respective SP CSI-RS resource set is activated for the at least one cell; and in the second value, the A / D bit field indicates that the respective SP CSI-RS resource set is deactivated for the at least one cell.

9. The apparatus of claim 7, wherein: the respective SP CSI-RS resource comprises an SP-nonzero power (NZP) CSI-RS resource set associated with the identifier for the at least one cell.

10. The apparatus of claim 5, wherein: the at least one field further comprises an inference measurement (IM) field.

11. The apparatus of claim 10, whereinin the second value, the second bit field further indicates that the IM field is set to zero for the at least one cell.

12. The apparatus of claim 10, wherein: the at least one field further comprises an SP CSI-RS resource set identifier field; and in the second value, the second bit field further indicates that the IM field and the SP CSI-RS resource set identifier field are at least one of set to zero for the at least one cell, not encoded, or to be ignored.

13. The apparatus of claim 10, wherein the SP CSI-RS resource set identifier field comprises a bitstring; and the IM field is configurable between the first value and the second value.

14. The apparatus of claim 13, wherein: in the second value, the second bit field and the IM field indicate that the bitstring of the SP CSI-RS resource set identifier field comprises an index of a SP CSI-IM resource set associated with the identifier for the at least one cell.

15. The apparatus of claim 5, wherein: the at least one field further comprises at least one transmission configuration indication (TCI) field comprising a respective bitstring; and in the second value, the second bit field indicates that the respective bitstring of the at least one TCI field comprises a TCI state identifier for the at least one cell.

16. The apparatus of claim 5, wherein: the at least one field further comprises a third field associated with bandwidth part (BWP) information; in the second value, the second bit field indicates at least one of: the third field is at least one of i) not encoded or ii) to be ignored in the generating of the at least one LI measurement; or the activation or deactivation of the at least one SP CSI-RS resource set applies to an active BWP for the current serving cell; orthe activation or deactivation of the at least one SP CSI-RS resource set applies to a BWP for the at least one cell.

17. The apparatus of claim 16, wherein: the at least one field further comprises a BWP field comprising a bitstring; in the second value, the second bit field indicates that the bitstring comprises a downlink (DL) BWP identifier for the current serving cell; and the instructions, when executed by the at least one processor, further cause the apparatus to: apply the active DL BWP for the current serving cell to at least one LI measurement based at least in part on the DL BWP identifier.

18. The apparatus of claim 5, wherein: the at least one field further comprises a third field associated with BWP information; and in the second value, the second bit field indicates: the third field is at least one of to be ignored in generation of at least one LI measurement; and the instructions, when executed by the at least one processor, further cause the apparatus to: apply a DL BWP of a primary cell of the network node to the at least one LI measurement.

19. The apparatus of any of claims 1-17, wherein: the control message embodies a medium access control (MAC) control element (CE).

20. The apparatus of any of claims 1-17, wherein: the control message comprises a logical channel identifier.

21. The apparatus of any of claims 1-20, wherein: the network node embodies a gNodeB.

22. The apparatus of any of claims 1-21, wherein:the apparatus embodies a user equipment (UE).

23. A method according to any of claims 1-22.

24. An apparatus comprising means for performing the method of claim 23.

25. A computer program product comprising at least one non-transitory computer- readable storage medium having computer-executable program code instructions stored therein, the computer-executable program code instructions comprising program code instructions configured to perform the method of claim 23.

26. 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: provision to a UE configuration data for at least one CSI-RS of at least one cell, wherein the configuration data indicates at least one SP CSI-RS resource set for a respective CSI-RS; and provision to the UE a control message associated with the at least one CSI- RS of the at least one cell, wherein at least one field of the control message indicates i) whether the at least one cell is a serving cell or a candidate cell, and ii) whether an activation or a deactivation of the at least one SP CSI-RS resource set applies to the at least one cell.

27. The apparatus of claim 26, wherein: the control message causes the UE to generate at least one LI measurement on the at least one CSI-RS U of the at least one cell of based at least in part on the control message; and the instructions, when executed by the at least one processor, further cause the apparatus to: receive from the UE a report comprising the at least one LI measurement on the at least one CSI-RS for the at least one cell.

28. The apparatus of claim 27, wherein the instructions, when executed by the at least one processor, further cause the apparatus to: provision a second control message to the UE to cause the UE to execute an LTM cell switch from a current serving cell to a respective cell of the at least one cell, wherein the second control message is based at least in part on the report.

29. The apparatus of claim 26, wherein: the at least one field comprises a cell identifier bit field comprising an identifier for the at least one cell.

30. The apparatus of claim 29, wherein: the at least one field further comprises a second bit field configurable between a first value and a second value; in the first value, the second bit field indicates the at least one cell is a serving cell; and in the second value, the second bit field indicates the at least one cell is a candidate cell.

31. The apparatus of claim 30, wherein: in the second value, the second bit field indicates that the candidate cell is an LTM candidate cell.

32. The apparatus of claim 30, wherein: the at least one field further comprises a third bit field comprising a bitstring; and in the second value, the second bit field further indicates that the bitstring of the third bit field comprises an identifier for a respective SP CSI-RS resource set of the at least one SP CSI-RS resource set for the respective CSI-RS of the at least one cell.

33. The apparatus of claim 32, wherein: the at least one field further comprises an A / D field configurable between the first value and the second value; in the first value, the A / D field indicates that the respective SP CSI-RS resource set is activated for the at least one cell; andin the second value, the A / D bit field indicates that the respective SP CSI-RS resource set is deactivated for the at least one cell.

34. The apparatus of claim 32, wherein: the respective SP CSI-RS resource set comprises an SP-NZP CSI-RS resource set associated with the identifier for the at least one cell.

35. The apparatus of claim 30, wherein: the at least one field further comprises an IM field.

36. The apparatus of claim 35, wherein in the second value, the second bit field further indicates that the IM field is set to zero for the at least one cell.

37. The apparatus of claim 35, wherein: the at least one field further comprises an SP CSI-RS resource set identifier field; and in the second value, the second bit field further indicates that the IM field and the SP CSI-RS resource set identifier field are at least one of set to zero for the at least one cell, not encoded, or to be ignored.

38. The apparatus of claim 35, wherein the SP CSI-RS resource set identifier field comprises a bitstring; and the IM field is configurable between the first value and the second value.

39. The apparatus of claim 38, wherein: in the second value, the second bit field and the IM field indicate that the bitstring of the SP CSI-RS resource set identifier field comprises an index of a SP CSI-IM resource set associated with the identifier for the at least one cell.

40. The apparatus of claim 30, wherein: the at least one field further comprises at least one TCI field comprising a respective bitstring; andin the second value, the second bit field indicates that the respective bitstring of the at least one TCI field comprises a TCI state identifier for the at least one cell.

41. The apparatus of claim 30, wherein: the at least one field further comprises a third field associated with bandwidth part (BWP) information; in the second value, the second bit field indicates at least one of the third field is at least one of i) not encoded or ii) to be ignored in the generating of the at least one LI measurement; the activation or deactivation of the at least one SP CSLRS resource set applies to an active BWP for the current serving cell; or the activation or deactivation of the at least one SP CSLRS resource set applies to a BWP for the at least one cell.

42. The apparatus of claim 41, wherein: the at least one field further comprises a BWP field comprising a bitstring; in the second value, the second bit field indicates that the bitstring comprises a downlink (DL) BWP identifier for the current serving cell; and the control message further causes the UE to: apply the active DL BWP for the current serving cell to at least one LI measurement based at least in part on the DL BWP identifier.

43. The apparatus of claim 30, wherein: the at least one field further comprises a third field associated with BWP information; and in the second value, the second bit field indicates: the third field is at least one of to be ignored in generation of at least one LI measurement; and the control message further causes the UE to: apply a DL BWP of a primary cell of to the at least one LI measurement.

44. The apparatus of any of claims 26-43, wherein: the control message embodies a MAC CE.

45. The apparatus of any of claims 26-43, wherein: the control message comprises a logical channel identifier.

46. The apparatus of any of claims 26-45, wherein: the apparatus embodies a gNodeB.

47. A method according to any of claims 26-46.

48. An apparatus comprising means for performing the method of claim 47.

49. A computer program product comprising at least one non-transitory computer- readable storage medium having computer-executable program code instructions stored therein, the computer-executable program code instructions comprising program code instructions configured to perform the method of claim 47.

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