Channel state information measurement and reporting

Abstract

In some examples, apparatus for user equipment comprises at least one processor, and at least one memory comprising instructions that, when executed by the at least one processor, cause the apparatus at least to receive a cell switch command, CSC, comprising a first field indicating that at least one second field of the CSC is reused to comprise information for at least one of channel state information, CSI, measurements or CSI reporting, and determine, based on the information in the at least one second field, a configuration for the at least one of the CSI measurements or CSI reporting on at least one candidate cell for a cell switch.

Description

[0001] CHANNEL STATE INFORMATION MEASUREMENT AND REPORTING

[0002] Technical Field

[0003] Various example embodiments relate generally to cell switch operations in a wireless communication system.

[0004] Background

[0005] Channel State Information (CSI) plays a crucial role in modern wireless communication systems, particularly in 5G and beyond. CSI refers to the knowledge of current conditions in the communication channel between transmitter and receiver.

[0006] In the context of mobility management and handovers, acquiring CSI for candidate cells becomes important. Recent 3rd Generation Partnership Project (3GPP) discussions have focused on enabling UEs to acquire and report CSI for candidate cells before or immediately after receiving a cell switch command. This approach aims to reduce the need for additional measurements after a cell switch, thereby improving efficiency and reducing latency.

[0007] Summary

[0008] An objective of the present disclosure is to provide enhancements to signalling for candidate cell Channel State Information (CSI) measurements and reporting during handover procedures in wireless networks. It addresses the need for efficient encoding of CSI measurement and reporting instructions within the Cell Switch Command (CSC) Medium Access Control (MAC) Control Element (CE) or handover command (RRC message).

[0009] The foregoing and other objectives are achieved by the features of the independent claims.

[0010] Further implementation forms are apparent from the dependent claims, the description and the Figures.Brief Description of the Drawings

[0011] In order that the present disclosure may be more readily understood, embodiments will now be described, by way of example, with reference to the accompanying drawings, in which:

[0012] Figure l is a schematic representation of a structure of a CSC, according to an example; Figure 2 is a schematic representation of a structure of a CSC, according to an example; Figure 3 is a schematic representation of a structure of a CSC, according to an example; Figure 4 is a schematic representation of part of a structure of a CSC, according to an example;

[0013] Figure 5 is a schematic representation of part of a structure of a CSC, according to an example;

[0014] Figure 6 is a schematic representation of a structure of a CSC, according to an example; Figure 7 is a signaling chart, according to an example; and

[0015] Figure 8 is a schematic representation of a machine according to an example.

[0016] Detailed Description

[0017] Example embodiments are described below in sufficient detail to enable those of ordinary skill in the art to embody and implement the systems and processes herein described. It is important to understand that embodiments can be provided in many alternate forms and should not be construed as limited to the examples set forth herein.

[0018] Accordingly, while embodiments can be modified in various ways and take on various alternative forms, specific embodiments thereof are shown in the drawings and described in detail below as examples. There is no intent to limit to the particular forms disclosed. On the contrary, all modifications, equivalents, and alternatives falling within the scope of the appended claims should be included. Elements of the example embodiments areconsistently denoted by the same reference numerals throughout the drawings and detailed description where appropriate.

[0019] The terminology used herein to describe embodiments is not intended to limit the scope. The articles “a,” “an,” and “the” are singular in that they have a single referent, however the use of the singular form in the present document should not preclude the presence of more than one referent. In other words, elements referred to in the singular can number one or more, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes,” and / or “including,” when used herein, specify the presence of stated features, items, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, items, steps, operations, elements, components, and / or groups thereof. The term “and / or” is only an association relationship for describing associated objects and represents that three relationships may exist such that A and / or B may indicate that A exists alone, A and B exist at the same time, or B exists alone. The character “ / ” generally represents that the associated objects are in an “or” relationship.

[0020] Unless otherwise defined, all terms (including technical and scientific terms) used herein are to be interpreted as is customary in the art. It will be further understood that terms in common usage should also be interpreted as is customary in the relevant art and not in an idealized or overly formal sense unless expressly so defined herein.

[0021] The following contains specific information related to implementations of the present disclosure. The drawings and their accompanying detailed disclosure are merely directed to implementations. However, the present disclosure is not limited to these implementations. Other variations and implementations of the present disclosure will be obvious to those skilled in the art.

[0022] The phrases “in one implementation,” or “in some implementations,” may each refer to one or more of the same or different implementations. The term “coupled” is defined as connected whether directly or indirectly through intervening components and is not necessarily limited to physical connections. The expression “at least one of A, B and C” or “at least one of the following: A, B and C” means “only A, or only B, or only C, or any combination of A, B and C.”The terms “system” and “network” may be used interchangeably.

[0023] For the purposes of explanation and non-limitation, specific details such as functional entities, techniques, protocols, and standards are set forth for providing an understanding of the present disclosure. In other examples, detailed disclosure of well-known methods, technologies, systems, and architectures are omitted so as not to obscure the present disclosure with unnecessary details.

[0024] Persons skilled in the art will immediately recognize that any network function(s) or algorithm(s) disclosed may be implemented by hardware, software or a combination of software and hardware. Disclosed functions may correspond to modules which may be software, hardware, firmware, or any combination thereof. A software implementation may include machine- and / or computer- readable and / or executable instructions stored on a machine- and / or computer-readable medium such as memory or other types of storage devices. One or more microprocessors or general-purpose computers with communication processing capability may be programmed with corresponding executable instructions and perform the disclosed network function(s) or algorithm(s).

[0025] The microprocessors or general-purpose computers may include Applications Specific Integrated Circuitry (ASIC), programmable logic arrays, and / or using one or more Digital Signal Processor (DSPs). Although some of the disclosed implementations are oriented to software installed and executing on computer hardware, alternative implementations implemented as firmware or as hardware or as a combination of hardware and software are well within the scope of the present disclosure. The computer readable medium includes but is not limited to Random Access Memory (RAM), Read Only Memory (ROM), Erasable Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable Read-Only Memory (EEPROM), flash memory, Compact Disc Read-Only Memory (CD-ROM), magnetic cassettes, magnetic tape, magnetic disk storage, or any other equivalent medium capable of storing computer-readable instructions.

[0026] Examples described may be implemented in a communication network, such as any of the following radio access technologies (RATs): Universal Mobile Telecommunication System (UMTS, 3G) based on basic wideband-code division multiple access (W-CDMA), high-speed packet access (HSPA), Long Term Evolution (LTE), LTE-Advanced, and enhanced LTE (eLTE), 5G (also called NR), or any future RAT such as 6G.

[0027] As used herein, the term “network device” or “network node” refers to a node in a communication network via which user equipment may access the network and / or which is capable of controlling radio communication and managing radio resources within a cell. The network node or network device may be referred to as a base station (BS), an access point (AP) or an access node. The network device may be, depending on the applied technology, for example, a node B (NodeB or NB), an evolved NodeB (eNodeB or eNB), an NR NB (also referred to as a gNB), a Remote Radio Unit (RRU), a radio head (RH), a remote radio head (RRH), a relay, an Integrated Access and Backhaul (IAB) node, a low power node, a non-terrestrial network (NTN) or non-ground network device such as a satellite network device, a low earth orbit (LEO) satellite and a geosynchronous earth orbit (GEO) satellite, or an aircraft network device.

[0028] Moreover, in connection of split radio access network (RAN), the network device may refer to a centralised unit (CU) of a base station and / or a distributed unit (DU) of a base station. An interface between CU and DU may be referred to as an Fl interface in NR. In the split RAN architecture, node operations may be carried out, at least partly, in the central / centralized unit, CU, (e.g. server, host or node) operationally coupled to the DU, (e.g. a radio head / node). One CU may control one or more DUs, acting at least as transmit / receive (Tx / Rx) nodes. In some embodiments, the DUs may comprise e.g. a radio link control (RLC), medium access control (MAC) layer and a physical (PHY) layer, whereas the CU may comprise the layers above RLC layer, such as a packet data convergence protocol (PDCP) layer, a radio resource control (RRC) and an internet protocol (IP) layers. Other functional splits are possible too. In practice, any processing task may be performed in either the CU or the DU and the boundary where the responsibility is shifted between the CU and the DU may depend on the applied implementation.

[0029] The term “terminal device” refers to any end device that may be capable of wireless communication. By way of example, a terminal device may be referred to as a communication device, user equipment (UE), a Subscriber Station (SS), or a MobileStation (MS). The terminal device may include a mobile phone, a cellular phone, a smart phone, voice over IP (VoIP) phones, wireless local loop phones a tablet, a wearable terminal device, a personal digital assistant (PDA), portable computers, desktop computer, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback appliances, vehicle-mounted wireless terminal devices, USB dongles, an Internet of Things (loT) device, a watch or other wearable, a head-mounted display (HMD), a vehicle, a drone, a medical device and applications (e.g., remote surgery), an industrial device and applications (e.g., a robot and / or other wireless devices operating in an industrial and / or an automated processing chain contexts), a consumer electronics device, a device operating on commercial and / or industrial wireless networks, and the like.

[0030] A term “resource”, as used herein, may refer to radio resources in time domain, in frequency domain, in space domain, and / or in code domain. Some examples of resources include e.g. a physical resource block (PRB), a radio frame, a subframe, a time slot, a subband, a frequency region, a sub-carrier, a beam, etc. The term “transmission” and / or “reception” may refer to wirelessly transmitting and / or receiving via a wireless propagation channel on radio resources.

[0031] Certain acronyms and / or abbreviations may be used herein, such as for example:

[0032] CSI Chanel State Information

[0033] CSLRS Channel State Information Reference Signal

[0034] CSC Cell Switch Command

[0035] DCI Downlink Control Information

[0036] HO Handover

[0037] LI Layer 1

[0038] L2 Layer 2

[0039] L3 Layer 3

[0040] L3 Mobility Layer 3 Mobility or RRC level mobility

[0041] LTM Ll / 2-triggered Mobility

[0042] MAC Medium Access Control

[0043] MAC CE MAC Control ElementRS Reference Signal

[0044] RSRP Reference Signal Received Power

[0045] SP Semi-persistent

[0046] SSB Synchronization Signal Block

[0047] TA Timing Advance

[0048] In current systems, CSI acquisition typically occurs after a cell switch based on, e.g. a Layer3 handover or a conditional handover, or Layerl / Layer2 triggered mobility or a conditional LTM, which can lead to delays and inefficiencies. There is a growing need to enable early CSI acquisition, allowing user equipment (UE) to perform CSI measurements and reporting either before or simultaneously with the cell switch.

[0049] Although recent 3GPP discussions have focused on enabling UEs to acquire and report CSI for candidate cells before or immediately after receiving a cell switch command, the specific procedures for how and when UEs should measure CSI from candidate cells have not been fully defined. In particular, there is a need for efficient mechanisms to encode CSI measurement and reporting instructions within cell switch commands.

[0050] According to an example, methods and apparatus are described herein in relation to release 19 (R19) mobility enhancements, i.e., enhancements to Layer 1 / 2 triggered mobility (LTM) with CSLRS measurements where enabling CSI acquisition (e.g., acquiring channel information such as channel quality indicator (CQI), rank indicator (RI), precoding matric indicator (PMI), etc.) on candidate cell(s) based on CSLRS is one of the objectives. UE can then acquire and report the CSI parameters (CQI, PMI, RI, or / and LI) for a candidate cell, which then can be used for transmission / reception in a target cell after the cell switch. This would reduce the need for additional measurements for CSI acquisition in the target cell for initial transmissions / receptions.

[0051] As such, enhancements to signalling for candidate cell Channel State Information (CSI) measurements and reporting during handover procedures in wireless networks are provided.

[0052] In an example, UE can receive an RRC configuration message containing CSI measurement and reporting configurations for candidate cells. This configuration can beprovided either as part of the Layer 1 / 2 Triggered Mobility (LTM) configuration or within the candidate cell configuration.

[0053] Examples herein are applicable for LTM or L3 mobility (RRC level mobility), for example. Furthermore, any reference to a CSC may apply either to the LMT cell switch command or to a L3 handover command (e.g., RRC reconfiguration or the like).

[0054] The UE then receives a CSC that includes an indication for CSI measurement and reporting. According to an example, this indication can be implemented in several ways, such as, e.g.:

[0055] 1. A single bit indicating whether the UE should measure and report CSI for candidate cells.

[0056] 2. A bit indicating the presence of additional fields in the CSC that specify CSI reporting configuration(s). The additional fields may be dedicated to specify the CSI reporting configuration(s)

[0057] 3. Reusing existing field(s) in the CSC structure to convey CSLrelated information.

[0058] The existing fields may refer to that the field(s) may serve another purpose in another situation, as described herein.

[0059] For early CSI acquisition measurements for a target cell of the cell switch, the UE may therefore begin measurements after receiving a cell switch command. The measurement configuration, such as RS configuration and CSI reporting configuration, may be provided to the UE via RRC. However, the cell switch command may also include additional information, allowing the UE to determine the appropriate reporting and measurement configuration, for example, whether the UE is requested to report the measurements and which measurements. In this case we provide methods for encoding CSI measurement / reporting request indication in the LTM Cell switch command MAC CE

[0060] According to an example, an indication can be included in non-optional fields of the CSC to avoid increasing the size of the state-of-the-art message. For example, it may be included in the same octet as the Transmission Configuration Indicator (TCI) state identifier, or in the same octet as the downlink (or joint DL and UL) Transmission Configuration Indicator (TCI) state identifier. This has the benefit of including the CSIindication (either the CSI indication field indicating the presence of a further field or the CSI indication field) in a field that is not conditionally present. In one example, the UE may be configured with CSI measurements to be performed before, after, or during the cell switch triggered by the cell switch command. In one example the CSC may comprise at least a field associated with CSI reporting for the cell switch. The methods herein are applicable also for L3 handover (e.g., RRC based handover) or a combination of RRC and MAC CE based handover / cell switch.

[0061] Based on the CSC indication and the previously received configuration, the UE can measure and report CSI for candidate cells. The candidate cells may include all the candidate cells for the cell switch or a subset of candidate cells for the cell switch. This approach enables early CSI acquisition, potentially reducing latency and improving efficiency during cell switching operations.

[0062] The present disclosure is compatible with existing standards while providing flexibility for future enhancements and has applications in both 5G and future 6G systems.

[0063] Figure 1 is a schematic representation of a structure of a CSC, according to an example. In the example of figure 1, the CSC comprises a CSI indication field 101. The CSI indication field is included within a field of the CSC 100, for example in the same octet as the TCI state ID (for downlink or joint DL and UL).

[0064] In the example of figure 1, the CSI indication field 101 can indicate the presence of a further field of the CSC indicating CSI measurement / reporting related information for cell switch operations. In another embodiment, no such further fields is present in the CSC.

[0065] Based on a value indicated using the CSI indication field 101, a UE can determine whether to perform CSI measurements and / or CSI reporting on at least one candidate cell for a cell switch.

[0066] In one example, the CSI indication field 101 may refer to a CSI configuration (CSI reporting configuration or CSI resource configuration) comprising at least one of - CSI configuration for cell switch purposes, wherein the associated candidate cell is determined based on the further field in the cell switch command, or- CSI configuration for cell switch purposes, wherein the associated configuration is determined based on the RRC reconfiguration of the candidate cell(s) indicated by the cell switch command, e.g. the CSI indication field may serve as a toggle enabling / disabling the CSI configuration(s) configured for the candidate cell(s) in the RRC reconfiguration, or

[0067] - CSI configuration of the target candidate ID indicated by the cell switch command, or LTM (or L3) CSI configuration of the target candidate ID indicated by the cell switch command, or

[0068] - CSI configuration across all the candidate cells and the resource sets is specific to candidate cell indicated by the CSC.

[0069] For example, when the CSI indication field 101 is set to first value (e.g., CSI = 0) it can indicate that a CSI related field is not present in the CSC. This may indicate to the UE that it is not requested / indicated to perform CSI measurements as part of cell switch operation.

[0070] When the CSI indication field 101 is set to a second value (e.g., CSI = 1) it can indicate the presence of at least one further field in the CSC providing an indication of CSI measurement / reporting for cell switch operations. This may indicate that UE is requested / indicated to perform CSI measurements as part of cell switch operation based on the information provided in the at least one further field.

[0071] Figure 2 is a schematic representation of a structure of a CSC, according to an example. In the example of figure 2, the at least one further field described above with reference to figure 1 may comprise a field indicating a report configuration ID, such as a report configuration ID field in octet 8 (201). In one example, the at least one further field may indicate or refer to the CSI resource configuration identifier. In one example, the at least one further field may indicate or refer to the CSI resource configuration identifier associated with the candidate cell. The UE can measure the CSI resources indicated by the CSI resource configuration identifier. In one example, the CSI resource configuration identifier or reporting configuration identifier may be interpreted in combination with the target cell ID / candidate cell configuration of the CSC.In one example, the at least one further field comprising CSI related information may be present in the octet following the TCI state field(s). In one example, the at least one further field comprising CSI related information may be present in the octet following the TCI state field(s) if random access related fields are not present (e.g., based on the indication of the at least one field, e.g., C bit). In one example, the at least one further field comprising CSI related information may be present in the octet following random access information related fields if the fields are indicated to be present (e.g., based on the indication of the at least one field, e.g., C bit).

[0072] In any of the examples herein, the reporting configuration (identified by a reporting configuration identifier) may further point or refer to the resource configuration associated with the reporting configuration.

[0073] According to an example, the report configuration ID field may refer to a measurement / reporting configuration which is used for cell switch operations based on a candidate cell identifier field of the CSC MAC CE (e.g., a target config ID), wherein the measurement / reporting configuration is configured as part of the LTM configuration. In some examples a candidate cell may be associated with a CSI measurement / reporting configuration dedicated for the certain candidate cell.

[0074] In some examples a candidate cell may be associated with a CSI measurement / reporting configuration configured for candidate cells.

[0075] In an example, the information of the indicated reporting configuration ID can be sent to a target cell / DU from a serving cell / DU, for example, in a cell switch notification message. This may be done via CU (e.g., source DU

[0076]

[0077] target DU). In case of inter-CU, this may be sent via a source CU and a target CU (e.g., source DU

[0078]

[0079] source target CU target DU). Note: this is to let the target cell know about the indicated report configuration in case multiple report configuration are configured for the target cell

[0080] The report configuration ID field may refer to a measurement / reporting configuration which is used for cell switch operations based on a candidate cell identifier field of the CSC MAC CE (e.g., target config ID), wherein the measurement / reporting configurationis configured as part of the candidate configuration or associated with the candidate configuration.

[0081] Figure 3 is a schematic representation of a structure of a CSC, according to an example. In the example of figure 3, the report configuration ID field can be indicated as a bitmap 301. The CSI measurement / reporting request for one or more report configuration IDs may be indicated in the bitmap 301. Each bit field of bitmap 301 may map to a CSI reporting configuration ID (e.g., in ascending order of the configuration ID to the bit positions). In the example of figure 1, the bit fields can be labeled as Ridl, Rid2 ... Ridn. The reporting configuration bit fields may refer to reporting configurations for specific candidate cells. The reporting configuration bit fields may refer to reporting configurations for LTM candidate cells. When the bit for the certain bit position is set to a first value (e.g., Rid=0), it indicates a CSI measurement request for the reporting configuration ID associated with the bitfield. When the bit for the certain bit position is set to a second value (e.g., Rid=l), it indicates a UE CSI measurement request for a reporting configuration ID associated with the bitfield.

[0082] According to an example, the report configuration ID fields shown in figure 2 and figure 3 (201; 301) can always be present if a UE is configured with LTM CSI reporting, and the field indicates whether the network requests the CSI and indicates the reporting configuration(s) that network request CSI measurements. One specific value may be used to indicate that the network does not request CSI measurements, for example, when the field indicating the reporting configuration is set to ‘FFFF’.

[0083] Figure 4 is a schematic representation of part of a structure of a CSC, according to an example. In the example of figure 4, the CSI indication field and the report configuration ID field are in the same octet. This field may be present if, e.g., the UE is configured with CSI acquisition for cell switch operations.

[0084] With reference to figures 1 to 4, the CSI indication field may be included in the same octet (field) as the TCI state ID. In one example, the CSI indication field may be included in the octet associated with the TCI state ID. In one example the field can be a TCI state ID (joint DL and UL). In one example the field can be a TCI state ID for UL. Accordingly, the TCI state fields are always present. In an example, the reportconfiguration ID field may be interpreted in combination with a target config ID, i.e., the combination of a report configuration ID field and a target configuration ID field can be used to indicate a CSI measurement / reporting configuration.

[0085] In an example, the report configuration ID field may point to the reporting configuration ID that is specific for CSI reporting as part of a cell switch.

[0086] According to an example, a CSC can comprise a CSI indication field that is comprised as part of (or as a reuse or repurposing of) an existing / preexisting field of the CSC. The CSI indication field can be used to indicate the presence of at least one additional field for the CSC configured to provide CSI measurement / reporting-related information.

[0087] For example, a preexisting timing advance command, TAC, field can be used to provide an indication of the presence (or absence) of CSI information in the CSC. In the context of a CSC MAC CE, a C bit is a field that indicates the presence of contention-free Random-Access Resources, CFRA, information. Specifically, when the C bit is set to 1, it indicates that the following fields are present in the CSC MAC CE: Random Access Preamble index field, S / U field, SS / PBCH index field, PRACH Mask index field, Repetition number field, and the reserved bits in the same octet. When the C bit is set to 0, it indicates that these fields are absent from the CSC MAC CE1.

[0088] According to an example, the C bit can be repurposed to indicate CSI-related information. For example, if the TAC field indicates a valid Timing Advance (TA) value, the C bit may be used to indicate the presence of CSI information in the CSC instead of contention-free Random-Access Resources. If the TAC field indicates no valid TA value and the C bit indicates that contention-free Random-Access preambles are not present, the octets normally used for CFRA random access indication may be repurposed to signal CSI-related information.

[0089] For example, if the TAC field indicates a value other than, e.g., FFF (i.e., it indicates a valid TA value) the C bit may indicate the presence of CSI information in the CSC. This means that CFRA resources are not present. In one example, the octet 5 field is present if the C field indicates the presence of CSI. It may comprise CSI related information signaling the CSI report configuration ID on bits reserved for “Random Access Preamble Index”, or in a combination derived from the “SS / PBCH index” and “Random AccessPreamble Index” fields for example. In one example, the C bit may indicate the CSI request.

[0090] If the TAC field indicates a value, e.g., FFF (i.e., it indicates a non-valid TA value) and the C bit indicates the presence of CFRA preambles, the R fields in octet 7 (comprising repetition number and S / U field) can be used to indicate CSI related information. For example, if the CFRA fields are present, the R bits can comprise the reporting configuration ID for which the CSI acquisition is triggered.

[0091] Figure 5 is a schematic representation of part of a structure of a CSC, according to an example. In the example of figure 5, a report configuration ID is depicted in the octet comprising the S / U / repetition number fields (e.g., octet 7).

[0092] If the TAC field indicates a value, e.g., FFF (i.e., indicates a non-valid TA value) and the C bit indicates that CFRA preambles are not present, the octet 5 (or alternatively at least one of octet 5, 6 or 7) may comprise CSI related information signaling the CSI report configuration ID or CSI Request indicator on the bit(s) reserved for CFRA random access indication. For example, for octet 5, the fields “Random Access Preamble Index”, or a combination derived from the “SS / PBCH index” and “Random Access Preamble Index” fields can be reused for CSI indication.

[0093] Figure 6 is a schematic representation of a structure of a CSC, according to an example. The example of figure 6 depicts a CSC command as specified in Release 18.

[0094] According to an example, additional enhancements to RRC signaling for CSI acquisition during cell switch operations are provided. For example, in respect of RRC configuration changes, a new parameter ("CSI-Report-on-CS") can be used as part of the candidate LTM configuration. This parameter can be used to indicate whether the CSI report is determined based on the MAC CE. In one example, this parameter can be used to indicate whether the CSI report is implicitly based on the candidate ID, and / or to specify if an explicit report config ID will be provided in the MAC CE.

[0095] Additional RRC changes for CSI Report without RRC decoding can be implemented using a new parameter for CSI-Report that can be added to the LTM Candidateconfiguration (within the RRC Configuration or RRC container of the Candidate, e.g., within Itm-CandidateConfig which contains RRC Configuration). This parameter can map to candidate CSI-RS information (outside or not included or in other than) the RRC configuration of the Candidate (or candidate cell or target cell) to enable a UE to refer to this parameter, CSI-RS information, associated with the report configuration information without needing to decode the full RRC configuration. It allows the UE to start CSI measurements earlier without any decoding of the RRC message, or it allows the UE to start CSI measurements earlier, potentially as soon as it begins decoding the RRC message.

[0096] In an example, UEs may prioritize fast / early processing (early ASN.l decoding or / and processing of RRC configuration) for candidates configured for CSI Reporting. This behavior can be specified as part of the UE requirements when CSI reporting is enabled for cell switch operations.

[0097] Figure 7 is a signaling chart, according to an example. In the example of figure 7, the signaling chart depicts the procedure for enabling CSI acquisition during Layer 1 / 2 Triggered Mobility (LTM) operations, specifically in the context of cell switch or handover (HO). At 707, configuration for mobility operation, a network provides UE 701 with RRC configurations for mobility operations. These configurations include CSI measurement and reporting settings for candidate cells. The RRC message can specify periodic CSI-RS resources (reference signals used by the UE to measure CSI parameters such as Channel Quality Indicator (CQI), Rank Indicator (RI), Precoding Matrix Indicator (PMI), and Layer Indicator (LI)).

[0098] At 709, UE 701 performs mobility-related measurements based on the provided RRC configuration. These measurements may include, e.g., CSI acquisition for candidate cells using configured CSI-RS resources, and / or other mobility-related signal quality evaluations (e.g., Synchronization Signal Block (SSB) measurements). UE 701 can compile these measurements into a report that will be sent to the serving cell 703. That is, at 711, UE 701 sends a measurement report to its serving cell 703. In an example, the report can include, e.g., signal quality metrics for candidate cells, CSI parameters obtained from periodic CSI-RS resources, if applicable, etc. The serving cell 703 can usethis information to decide whether a cell switch or handover is necessary and identify the best candidate cell as the target.

[0099] At 713, once the serving cell 703 decides on a target cell, it sends a CSC or HO Command to the UE 701. In an example, this command can comprise a target configuration ID to identify the candidate cell 705 selected as the target, and a CSI Indication Field to specify whether the UE should perform CSI measurements and reporting for the target cell. Additional fields may include specific CSI reporting configurations, such as Report Configuration ID or bitmap fields indicating multiple configurations. This ensures that the UE 701 knows which candidate cell 705 to switch to and how to perform further CSI acquisition.

[0100] At 715, after receiving the CSC / HO command, the UE 701 performs additional CSI measurements on the candidate cell 705 using its measurement resources. The exact behaviour can depend on the indication in the CSC. For example, if CSI is requested, the UE 701 can measure parameters such as CQI, RI, PMI, and LI using periodic or semi-persistent CSLRS resources associated with the target cell. The measurement configuration may be derived from fields in the CSC or pre-configured RRC settings. These measurements ensure that accurate channel state information is available for initial transmissions and receptions in the target cell after switching.

[0101] Accordingly, early CSI acquisition is enabled, and CSI measurements can be initiated before or during a cell switch operation, reducing latency and improving efficiency. The RRC configuration provides periodic or semi-persistent resources for CSI acquisition, while additional fields in CSC allow dynamic adjustments during handover. The measured CSI is reported either directly to the target cell or through intermediate signalling paths involving serving and candidate cells. This reduces service interruption during handover by enabling early acquisition of channel state information, minimises additional measurements needed after switching to a target cell, and ensures seamless operation by combining pre-configured RRC settings with dynamic CSC indications.

[0102] The signalling framework of figure 7 aligns with Rel-19 mobility enhancements under 3GPP discussions and is designed for efficient implementation in advanced 5G and future 6G networks.Examples in the present disclosure can be provided as methods, systems or machine-readable instructions, such as any combination of software, hardware, firmware or the like. Such machine-readable instructions may be included on a computer readable storage medium (including but not limited to disc storage, CD-ROM, optical storage, etc.) having computer readable program codes therein or thereon.

[0103] The present disclosure is described with reference to flow charts and / or block diagrams of the method, devices and systems according to examples of the present disclosure. Although the flow diagrams described above show a specific order of execution, the order of execution may differ from that which is depicted. Blocks described in relation to one flow chart may be combined with those of another flow chart. In some examples, some blocks of the flow diagrams may not be necessary and / or additional blocks may be added. It shall be understood that each flow and / or block in the flow charts and / or block diagrams, as well as combinations of the flows and / or diagrams in the flow charts and / or block diagrams can be realized by machine readable instructions.

[0104] The machine-readable instructions may, for example, be executed by a machine such as a general-purpose computer, a platform comprising user equipment such as a smart device, e.g., a smart phone, a special purpose computer, an embedded processor or processors of other programmable data processing devices to realize the functions described in the description and diagrams. In particular, a processor or processing apparatus may execute the machine-readable instructions. Thus, modules of apparatus may be implemented by a processor executing machine readable instructions stored in a memory, or a processor operating in accordance with instructions embedded in logic circuitry. The term 'processor' is to be interpreted broadly to include a CPU, processing unit, ASIC, logic unit, or programmable gate set etc. The methods and modules may all be performed by a single processor or divided amongst several processors.

[0105] Such machine-readable instructions may also be stored in a computer readable storage that can guide the computer or other programmable data processing devices to operate in a specific mode. For example, the instructions may be provided on a non-transitory computer readable storage medium encoded with instructions, executable by a processor.Figure 8 is a schematic representation of a machine according to an example. The machine 800 can be, e.g., a system or apparatus, network node, user equipment, or parts thereof. The machine 800 comprises a processor 803, and a memory 805 to store instructions 802, executable by the processor 803. The machine comprises a storage 809 that can be used to store data 811.

[0106] In an example, the instructions 807, executable by the processor 803, can cause the machine 800 (e.g., a UE 701) to receive a cell switch command, CSC, comprising a channel state information, CSI, indication field, determine a measurement configuration and / or a reporting configuration based on a value indicated using the CSI indication field, and perform CSI measurements and / or reporting according to the configuration.

[0107] In another example, the instructions 807, executable by the processor 803, can cause the machine 800 (e.g., a UE 701) to receive a cell switch command, CSC, comprising a channel state information, CSI, indication field, wherein the CSI indication field is included within a field of the CSC, and wherein the CSI indication field indicates the presence of at least one additional field for the CSC providing CSI measurement / reporting-related information, determine, based on a value indicated using the CSI indication field, whether to perform CSI measurements and / or CSI reporting on at least one candidate cell for a cell switch, and on the basis of the determination, perform CSI measurements and / or reporting using the CSI measurement / reporting-related information from the at least one additional field for the CSC.

[0108] In another example, the instructions 807, executable by the processor 803, can cause the machine 800 (e.g., a UE 701) to receive a cell switch command, CSC, comprising a first field adapted to indicate the presence of channel state information, CSI, within at least a second field of the CSC, determine, based on a value indicated in the first field, whether to perform CSI measurements and / or CSI reporting on at least one candidate cell for a cell switch using information interpreted from the at least one second field, and perform CSI measurements and / or reporting using the CSI measurement / reporting-related information from the at least one second field of the CSC.Accordingly, the machine 800 can implement a method for or indicating CSI measurement and reporting information during a cell switch operation in a wireless communication system.

[0109] Such machine-readable instructions may also be loaded onto a computer or other programmable data processing devices, so that the computer or other programmable data processing devices perform a series of operations to produce computer-implemented processing, thus the instructions executed on the computer, or other programmable devices provide an operation for realizing functions specified by flow(s) in the flow charts and / or block(s) in the block diagrams.

[0110] Further, the teachings herein may be implemented in the form of a computer or software product, such as a non-transitory machine-readable storage medium, the computer software or product being stored in a storage medium and comprising a plurality of instructions, e.g., machine readable instructions, for making a computer device implement the methods recited in the examples of the present disclosure.

[0111] In some examples, some methods can be performed in a cloud-computing or networkbased environment. Cloud-computing environments may provide various services and applications via the Internet. These cloud-based services (e.g., software as a service, platform as a service, infrastructure as a service, etc.) may be accessible through a web browser or other remote interface of the user equipment for example. Various functions described herein may be provided through a remote desktop environment or any other cloud-based computing environment.

[0112] A first aspect of the present disclosure provides apparatus for user equipment, UE, comprising at least one processor, and at least one memory comprising instructions that, when executed by the at least one processor, cause the apparatus at least to receive a cell switch command, CSC, comprising a first field indicating that at least one second field of the CSC is reused to comprise information for at least one of channel state information, CSI, measurements or CSI reporting, and determine, based on the information in the at least one second field, a configuration for the at least one of the CSI measurements or CSI reporting on at least one candidate cell for a cell switch.In an implementation of the first aspect, the at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to measure CSI for the at least one candidate cell using the information from the at least one second field within the CSC when the value indicated using the first field indicates the presence of the information. The first field can comprise a timing advance command field, TAC, and the at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to determine whether the TAC field indicates a valid timing advance value, and on the basis of determining that the TAC field indicates a valid timing advance value, determine that the at least one second field of the CSC comprises the information for at least one of channel state information, CSI, measurements or CSI reporting.

[0113] In an example, the at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to, on the basis of determining that the TAC field indicates an invalid timing advance value, determine that the at least one second field of the CSC is used for indicating contention-free random access resources for the cell switch. The at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to, on the basis of determining that the TAC field indicates a valid timing advance value, determine that the information for at least one of CSI measurements or CSI reporting is comprised in another field of the cell switch command. The cell switch command can further comprise a bit indicating whether the cell switch command comprises the information for at least one of CSI measurements or CSI reporting, and the at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to determine, based on a combination of a value of the bit and whether the TAC field indicates the valid timing advance value, a location of the information for at least one of CSI measurements or CSI reporting in the cell switch command. The at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to report measured CSI parameters to a target cell of the cell switch based on the value indicated using the first field.In an example, the information for at least one of CSI measurements or CSI reporting can comprise a configuration identifier referring to a configuration that comprises parameters for the at least one of CSI measurements or CSI reporting, and the at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to obtain the parameters for the at least one of CSI measurements or CSI reporting based on the configuration identifier. The configuration can be a Layerl / Layer2 triggered mobility configuration for a candidate cell associated with the configuration identifier, and the at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to decode at least one configuration for the at least one of CSI measurements or CSI reporting for the candidate cell, and perform the at least one of CSI measurements or CSI reporting before or during a cell switch operation with respect to the candidate cell. The at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to identify, from the same octet of the CSC that comprises the first field, a TCI state identifier field.

[0114] A second aspect of the present disclosure provides a method, performed by a user equipment, UE, the method comprising receiving a cell switch command, CSC, comprising a first field indicating that at least one second field of the CSC is reused to comprise information for at least one of channel state information, CSI, measurements or CSI reporting, and determining, based on the information in the at least one second field, a configuration for the at least one of the CSI measurements or CSI reporting on at least one candidate cell for a cell switch.

[0115] In an implementation of the second aspect, the method can further comprise measuring CSI for the at least one candidate cell using the information from the at least second field within the CSC when the value indicated using the first field indicates the presence of the information. The first field can be a timing advance command field, TAC, and the method can further comprise determining whether the TAC field indicates a valid timing advance value, and on the basis of determining that the TAC field indicates the valid timing advance value, determining that the second field of the CSC comprise the information for at least one of channel state information, CSI, measurements or CSI reporting.In an example, the method can further comprise, on the basis of determining that the TAC field indicates an invalid timing advance value, determining that the second field of the CSC is used for indicating contention-free random access resources for the cell switch. The method can further comprise, on the basis of determining that the TAC field indicates the valid timing advance value, determining that the information for at least one of CSI measurements or CSI reporting is comprised in another field of the cell switch command. The cell switch command can further comprise a bit indicating whether or not the cell switch command comprises the information for at least one of CSI measurements or CSI reporting, and the method can further comprise determining, based on a combination of a value of the bit and whether the TAC field indicates the valid timing advance value, a location of the information for at least one of CSI measurements or CSI reporting in the cell switch command. The method can further comprise reporting measured CSI parameters to a target cell of the cell switch based on the value indicated using the first field.

[0116] In an example, the information for at least one of CSI measurements or CSI reporting can comprise a configuration identifier referring to a configuration that comprises parameters for the at least one of CSI measurements or CSI reporting, and the method can further comprise obtaining the parameters for the at least one of CSI measurements or CSI reporting based on the configuration identifier. The configuration can be a Layerl / Layer2 triggered mobility configuration for a candidate cell associated with the configuration identifier, and the method can further comprise decoding at least one configuration for the at least one of CSI measurements or CSI reporting for the candidate cell, and performing the at least one of CSI measurements or CSI reporting before or during a cell switch operation with respect to the candidate cell. The method can further comprise identifying, from the same octet of the CSC that comprises the first field, a TCI state identifier field. The at least one second field can be included in the same octet as a Timing Advance Command, TAC, field for the CSC command when TAC indicates a valid timing advance value. The at least one second field can be included in at least one contention-free Random Access Resources field when a Timing Advance Command, TAC, field for the CSC command indicates no valid timing advance value.A third aspect of the present disclosure provides a computer-readable medium comprising instructions that, in response to execution by at least one processing circuitry, causes an apparatus to receive a cell switch command, CSC, comprising a first field indicating that at least one second field of the CSC is reused to comprise information for at least one of channel state information, CSI, measurements or CSI reporting, determine, based on the information in the at least one second field, a configuration for the at least one of the CSI measurements or CSI reporting on at least one candidate cell for a cell switch, and perform CSI measurements and / or reporting using the CSI measurement / reporting-related information from the at least one second field of the CSC.

[0117] A fourth aspect of the present disclosure provides apparatus for user equipment, UE, comprising at least one processor, and at least one memory comprising instructions that, when executed by the at least one processor, cause the apparatus at least to receive a cell switch command, CSC, comprising a channel state information, CSI, indication field, wherein the CSI indication field indicates the presence of at least one additional field in the CSC comprising configuration information for at least one of CSI measurement or CSI reporting, and determine, based on a value of the CSI indication field, whether to perform at least one of CSI measurements or CSI reporting on at least one candidate cell for a cell switch using the configuration information.

[0118] In an implementation of the fourth aspect, the value indicated using the CSI indication field can indicate a measurement request, and the at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to measure, based on the measurement request, CSI parameters for the at least one candidate cell using the at least one CSI measurement or reporting configuration information from the at least one additional field in the CSC .

[0119] In an example, the at least one additional field can comprise a configuration identifier field, and the at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to determine, based on the configuration identifier field, at least one of a measurement configuration or a reporting configuration for a candidate cell to be used for the at least one of CSI measurements or CSI reporting. The at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to receive at least oneof the measurement configuration or the reporting configuration for the candidate cell separately from the cell switch command, and use a value in the configuration identifier field to detect the measurement configuration for the candidate cell. At least one of the measurement configuration or the reporting configuration can be comprised in a Layerl / Layer2 triggered mobility configuration for the candidate cell. At least one additional field in the cell switch command can comprise an octet comprising at least one CSI reporting configuration identifier field. The octet can comprise a bitmap indicating CSI reporting configurations for a plurality of candidate cells. CSI indication field can be comprised in the same octet as the at least one additional field.

[0120] A fifth aspect of the present disclosure provides a method, performed by a user equipment, UE, the method comprising receiving a cell switch command, CSC, comprising a channel state information, CSI, indication field, wherein the CSI indication field indicates the presence of at least one additional field in the CSC comprising configuration information for at least one of CSI measurement or CSI reporting, and determining, based on a value of the CSI indication field, whether to perform at least one of CSI measurements or CSI reporting on at least one candidate cell for a cell switch using the configuration information.

[0121] In an implementation of the fifth aspect, the value indicated using the CSI indication field can indicate a measurement request, and the method can further comprise measuring, based on the measurement request, CSI parameters for the at least one candidate cell using the CSI measurement / reporting-related information from the at least one additional field for the CSC. The at least one additional field can comprise a configuration identifier field, and the method can further comprise determining, based on the candidate cell identifier field, at least one of a measurement configuration or a reporting configuration for a candidate cell to be used for the at least one of CSI measurements or CSI reporting. In an example, the method can further comprise receiving the measurement configuration or the reporting configuration for the candidate cell separately from the cell switch command, and using a value in the configuration identifier field to detect the measurement configuration for the candidate cell. The measurement configuration or the reporting configuration can be comprised in a Layerl / Layer2 triggered mobility configuration for the candidate cell. The at least one additional field in the cell switchcommand can be an octet comprising at least one CSI reporting configuration identifier field. The octet can comprise a bitmap indicating CSI reporting configurations for a plurality of candidate cells. CSI indication field can be comprised in the same octet as the at least one additional field. The value indicated using the CSI indication field can comprise a first value or a second value, wherein the first value indicates that the UE is not requested to perform at least one of CSI measurements or report CSI measurements, and wherein the second value indicates that the UE is requested to perform at least one of CSI measurements or report CSI measurements. Multiple configurations can be indicated using a bitmap, with each bit of the bitmap corresponding to a specific reporting configuration ID for candidate cells. At least one of the CSI indication field and the at least one additional field can be embedded within or comprised of non-optional octets of the structure of the CSC command.

[0122] A sixth aspect of the present disclosure provides a computer-readable medium comprising instructions that, in response to execution by at least one processing circuitry, causes an apparatus to receive a cell switch command, CSC, comprising a channel state information, CSI, indication field, wherein the CSI indication field indicates the presence of at least one additional field in the CSC comprising configuration information for at least one of CSI measurement or CSI reporting, determine, based on a value of the CSI indication field, whether to perform at least one of CSI measurements or CSI reporting on at least one candidate cell for a cell switch using the configuration information, and on the basis of the determination, perform at least one of CSI measurements or reporting using the CSI measurement / reporting-related information from the at least one additional field for the CSC.

[0123] A seventh aspect of the present disclosure provides an apparatus for user equipment, UE, comprising at least one processor, and at least one memory comprising instructions that, when executed by the at least one processor, cause the apparatus at least to receive a cell switch command, CSC, comprising a channel state information, CSI, indication field, wherein the CSI indication field is included within a field of the CSC, and determine, based on a value indicated using the CSI indication field, whether to perform at least one of CSI measurements or CSI reporting on at least one candidate cell for a cell switch.In an implementation of the seventh aspect, the at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to measure CSI parameters for the at least one candidate cell before the cell switch when the value indicated using the CSI indication field indicates a measurement request. In an example, at least one additional field can comprise a candidate cell identifier field indicating a candidate cell, and the at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to determine at least one of a CSI measurement configuration or CSI reporting configuration for the at least one candidate cell to be used for the at least one of CSI measurements or CSI reporting based on the candidate cell identifier field. The at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to decode, based on the candidate cell identifier field indicating the candidate cell, a configuration for the at least one of CSI measurements or CSI reporting from a radio resource control, RRC, configuration of the candidate cell, and perform, based on the configuration, the at least one CSI measurements or CSI reporting before or during the cell switch. The configuration for the at least one of CSI measurements or CSI reporting can be comprised in a Layerl / Layer2 triggered mobility configuration of the candidate cell.

[0124] In an example, the at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to report, to a target cell of the cell switch, measured CSI parameters of the target cell based on the value indicated using the CSI indication field. The at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to report measured CSI parameters using a medium access control, MAC, Control Element, MAC CE, or using Uplink Control Information, UCI or Radio Resource Control Message, RRC. The at least one memory can further comprise instructions that, when executed by the at least one processor, cause the apparatus at least to determine the CSI indication field on the basis of inclusion of a valid timing advance value in the CSC. The CSI indication field can be in the same octet as a transmission configuration indicator, TCI, state identifier field.An eighth aspect of the present disclosure provides a method, performed by a user equipment, UE, the method comprising receiving a cell switch command, CSC, comprising a channel state information, CSI, indication field, wherein the CSI indication field is included within a field of the CSC, and determining, based on a value indicated using the CSI indication field, whether to perform at least one of CSI measurements or CSI reporting on at least one candidate cell for a cell switch.

[0125] In an implementation of the eighth aspect, the value indicated using the CSI indication field can comprise a first value or a second value, wherein the first value indicates that the UE is not requested to perform at least one of CSI measurements or report CSI measurements, and wherein the second value indicates that the UE is requested to perform at least one of CSI measurements or report CSI measurements.

[0126] In an example, the method can further comprise measuring CSI parameters for the at least one candidate cell before the cell switch when the value indicated using the CSI indication field indicates a measurement request. At least one additional field can comprise a candidate cell identifier field indicating a candidate cell, and the method can further comprise determining at least one of a CSI measurement configuration or CSI reporting configuration for the at least one candidate cell to be used for the at least one of CSI measurements or CSI reporting based on the candidate cell identifier field. The method can further comprise decoding, based on the candidate cell identifier field indicating the candidate cell, a configuration for the at least one of CSI measurements or CSI reporting from a radio resource control, RRC, configuration of the candidate cell, and performing, based on the configuration, the at least one CSI measurements or CSI reporting before or during the cell switch. The configuration for the at least one of CSI measurements or CSI reporting can be comprised in a Layerl / Layer2 triggered mobility configuration of the candidate cell.

[0127] In an example, the method can further comprise reporting, to a target cell of the cell switch, measured CSI parameters of the target cell based on the value indicated using the CSI indication field. The method can further comprise reporting measured CSI parameters using a medium access control, MAC, Control Element, MAC CE, or using Uplink Control Information, UCI or Radio Resource Control Message, RRC. The method can further comprise determining the CSI indication field on the basis of inclusion of avalid timing advance value in the CSC. The CSI indication field can be in the same octet as a transmission configuration indicator, TCI, state identifier field. The CSI indication field can be determined based on inclusion of a valid timing advance value in the CSC. A ninth aspect of the present disclosure provides a computer-readable medium comprising instructions that, in response to execution by at least one processing circuitry, causes an apparatus to receive a cell switch command, CSC, comprising a channel state information, CSI, indication field, wherein the CSI indication field is included within a field of the CSC, determine, based on a value indicated using the CSI indication field, whether to perform at least one of CSI measurements or CSI reporting on at least one candidate cell for a cell switch, and perform at least one of CSI measurements or reporting according to the configuration.

[0128] While various embodiments have been described and / or illustrated herein in the context of fully functional computing systems, one or more of these exemplary embodiments may be distributed as a program product in a variety of forms, regardless of the particular type of computer-readable-storage media used to actually carry out the distribution. The embodiments disclosed herein may also be implemented using software modules that perform certain tasks. These software modules may include script, batch, or other executable files that may be stored on a computer-readable storage medium or in a computing system. In some embodiments, these software modules may configure a computing system to perform one or more of the exemplary embodiments disclosed herein. In addition, one or more of the modules described herein may transform data, physical devices, and / or representations of physical devices from one form to another.

[0129] The preceding description has been provided to enable others skilled in the art to best utilize various aspects of the exemplary embodiments disclosed herein. This exemplary description is not intended to be exhaustive or to be limited to any precise form disclosed. Many modifications and variations are possible without departing from the spirit and scope of the instant disclosure. The embodiments disclosed herein should be considered in all respects illustrative and not restrictive. Reference should be made to the appended claims and their equivalents in determining the scope of the instant disclosure.

Claims

CLAIMS:

1. Apparatus for user equipment, UE, comprising:at least one processor; andat least one memory comprising instructions that, when executed by the at least one processor, cause the apparatus at least to:receive a cell switch command, CSC, comprising a first field indicating that at least one second field of the CSC is reused to comprise information for at least one of channel state information, CSI, measurements or CSI reporting; anddetermine, based on the information in the at least one second field, a configuration for the at least one of the CSI measurements or CSI reporting on at least one candidate cell for a cell switch.

2. The apparatus of claim 1, the at least one memory further comprising instructions that, when executed by the at least one processor, cause the apparatus at least to:measure CSI for the at least one candidate cell using the information from the at least one second field within the CSC when the value indicated using the first field indicates the presence of the information.

3. The apparatus of claim 1 or 2, wherein the first field is a timing advance command field, TAC, and wherein the at least one memory further comprises instructions that, when executed by the at least one processor, cause the apparatus at least to:determine whether the TAC field indicates a valid timing advance value; and on the basis of determining that the TAC field indicates a valid timing advance value, determine that the at least one second field of the CSC comprises the information for at least one of channel state information, CSI, measurements or CSI reporting.

4. The apparatus of claim 3, the at least one memory further comprising instructions that, when executed by the at least one processor, cause the apparatus at least to: on the basis of determining that the TAC field indicates an invalid timing advance value, determine that the at least one second field of the CSC is used for indicating contention-free random access resources for the cell switch.

295. The apparatus of claim 4, the at least one memory further comprising instructions that, when executed by the at least one processor, cause the apparatus at least to: on the basis of determining that the TAC field indicates a valid timing advance value, determine that the information for at least one of CSI measurements or CSI reporting is comprised in another field of the cell switch command.

6. The apparatus of any preceding claim 3 to 5, wherein the cell switch command further comprises a bit indicating whether the cell switch command comprises the information for at least one of CSI measurements or CSI reporting, and wherein the at least one memory further comprises instructions that, when executed by the at least one processor, cause the apparatus at least to:determine, based on a combination of a value of the bit and whether the TAC field indicates the valid timing advance value, a location of the information for at least one of CSI measurements or CSI reporting in the cell switch command.

7. The apparatus of any preceding claim, the at least one memory further comprising instructions that, when executed by the at least one processor, cause the apparatus at least to:report measured CSI parameters to a target cell of the cell switch based on the value indicated using the first field.

8. The apparatus of any preceding claim, wherein the information for at least one of CSI measurements or CSI reporting comprises a configuration identifier referring to a configuration that comprises parameters for the at least one of CSI measurements or CSI reporting, and wherein the at least one memory further comprising instructions that, when executed by the at least one processor, cause the apparatus at least to:obtain the parameters for the at least one of CSI measurements or CSI reporting based on the configuration identifier.

9. The apparatus of claim 8, wherein the configuration is a Layerl / Layer2 triggered mobility configuration for a candidate cell associated with the configuration identifier,and wherein at least one memory further comprises instructions that, when executed by the at least one processor, cause the apparatus at least to:decode at least one configuration for the at least one of CSI measurements or CSI reporting for the candidate cell; andperform the at least one of CSI measurements or CSI reporting before or during a cell switch operation with respect to the candidate cell.

10. The apparatus of any preceding claim, the at least one memory further comprising instructions that, when executed by the at least one processor, cause the apparatus at least to:identify, from the same octet of the CSC that comprises the first field, a TCI state identifier field.

11. A method, performed by a user equipment, UE, the method comprising:receiving a cell switch command, CSC, comprising a first field indicating that at least one second field of the CSC is reused to comprise information for at least one of channel state information, CSI, measurements or CSI reporting; anddetermining, based on the information in the at least one second field, a configuration for the at least one of the CSI measurements or CSI reporting on at least one candidate cell for a cell switch.

12. The method of claim 11, further comprising:measuring CSI for the at least one candidate cell using the information from the at least second field within the CSC when the value indicated using the first field indicates the presence of the information.

13. The method of claim 11 or 12, wherein the first field is a timing advance command field, TAC, the method further comprising:determining whether the TAC field indicates a valid timing advance value; and on the basis of determining that the TAC field indicates the valid timing advance value, determining that the second field of the CSC comprise the information for at least one of channel state information, CSI, measurements or CSI reporting.

14. The method of claim 13, further comprising:on the basis of determining that the TAC field indicates an invalid timing advance value, determining that the second field of the CSC is used for indicating contention-free random access resources for the cell switch.

15. The method of claim 14, further comprising:on the basis of determining that the TAC field indicates the valid timing advance value, determining that the information for at least one of CSI measurements or CSI reporting is comprised in another field of the cell switch command.

16. The method of any of claims 13 to 15, wherein the cell switch command further comprises a bit indicating whether or not the cell switch command comprises the information for at least one of CSI measurements or CSI reporting, the method further comprising:determining, based on a combination of a value of the bit and whether the TAC field indicates the valid timing advance value, a location of the information for at least one of CSI measurements or CSI reporting in the cell switch command.

17. The method of any of claims 11 to 16, further comprising:reporting measured CSI parameters to a target cell of the cell switch based on the value indicated using the first field.

18. The method of any of claims 11 to 17, wherein the information for at least one of CSI measurements or CSI reporting comprises a configuration identifier referring to a configuration that comprises parameters for the at least one of CSI measurements or CSI reporting, the method further comprising:obtaining the parameters for the at least one of CSI measurements or CSI reporting based on the configuration identifier.

19. The method of claim 18, wherein the configuration is a Layer 1 / Layer2 triggered mobility configuration for a candidate cell associated with the configuration identifier, the method further comprising:decoding at least one configuration for the at least one of CSI measurements or CSI reporting for the candidate cell; andperforming the at least one of CSI measurements or CSI reporting before or during a cell switch operation with respect to the candidate cell.

20. The method of any of claims 11 to 19, further comprising:identifying, from the same octet of the CSC that comprises the first field, a TCI state identifier field.

21. The method of any of claims 11 to 20, wherein the at least one second field is included in the same octet as a Timing Advance Command, TAC, field for the CSC command when TAC indicates a valid timing advance value.

22. The method of any of claims 11 to 20, wherein the at least one second field is included in at least one contention-free Random Access Resources field when a Timing Advance Command, TAC, field for the CSC command indicates no valid timing advance value.

23. A computer-readable medium comprising instructions that, in response to execution by at least one processing circuitry, causes an apparatus to:receive a cell switch command, CSC, comprising a first field indicating that at least one second field of the CSC is reused to comprise information for at least one of channel state information, CSI, measurements or CSI reporting;determine, based on the information in the at least one second field, a configuration for the at least one of the CSI measurements or CSI reporting on at least one candidate cell for a cell switch; andperform CSI measurements and / or reporting using the CSI measurement / reporting-related information from the at least one second field of the CSC.

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