Random access procedure initiated for layer-1 / layer-2 triggered mobility cell switch

Abstract

Embodiments described herein relate to methods and apparatuses for a random access procedure initiated by a Layer-1 / Layer-2 Triggered Mobility cell switch. A method in a user equipment being served by a first cell of a first network node comprises: performing a random access, RA, procedure for a lower-layer triggered mobility, LTM, cell switch to a second cell; and determining first information associated with the RA procedure for the LTM cell switch to the second cell.

Description

[0001] RANDOM ACCESS PROCEDURE INITIATED FOR LAYER-1 / LAYER-2 TRIGGERED MOBILITY CELL SWITCH TECHNICAL FIELD Embodiments described herein relate to methods and apparatuses for a random access procedure initiated by a Layer-1 / Layer-2 Triggered Mobility cell switch. BACKGROUND Further NR mobility enhancements in 3GPP Rel-18 As part of the 3rd Generation Partnership Project (3GPP) Release 18, a new work item known as Further New Radio (NR) mobility enhancements is about to start. This work item aims to, among other things, specify Layer-1 / Layer-2 (L1 / L2)-based inter-cell mobility. According to the work item description (WID) RP-211586, 3GPP: Further enhancements on MIMO for NR, Samsung, 3GPP TSG RAN Meeting #92e, Electronic Meeting, June 14-18, 2021, the following is included as one objective of the work: 1. To specify mechanism and procedures of L1 / L2 based inter-cell mobility for mobility latency reduction: o Configuration and maintenance for multiple candidate cells to allow fast application of configurations for candidate cells [RAN2, RAN3] o Dynamic switch mechanism among candidate serving cells (including SpCell and SCell) for the potential applicable scenarios based on L1 / L2 signalling [RAN2, RAN1] o L1 enhancements for inter-cell beam management, including L1 measurement and reporting, and beam indication [RAN1, RAN2] - Note 1: Early RAN2 involvement is necessary, including the possibility of further clarifying the interaction between this bullet with the previous bullet o Timing Advance management [RAN1, RAN2] o CU-DU interface signaling to support L1 / L2 mobility, if needed [RAN3] Note 2: FR2 specific enhancements are not precluded, if any. Note 3: The procedure of L1 / L2 based inter-cell mobility are applicable to the following scenarios: ^ Standalone, CA and NR-DC case with serving cell change within one CG ^ Intra-DU case and intra-CU inter-DU case (applicable for Standalone and CA: no new RAN interfaces are expected) ^ Both intra-frequency and inter-frequency Both FR1 and FR2 ^ Source and target cells may be synchronized or non-synchronized According to the work item description RP-211586, the following is written as part of the justification: “When the user equipment (UE) moves from the coverage area of one cell to another cell, at some point a serving cell change needs to be performed. Currently serving cell change is triggered by Layer- 3 (L3) measurements and is done by Radio Resource Control (RRC) signalling triggered Reconfiguration with Synchronisation for change of Primary Cell (PCell) and Primary Cell of the secondary cell group (PSCell), as well as release add for Secondary Cells (SCells) when applicable. All cases involve complete L2 (and L1) resets, leading to longer latency, larger overhead and longer interruption time than beam switch mobility. The goal of L1 / L2 mobility enhancements is to enable a serving cell change via L1 / L2 signalling, in order to reduce the latency, overhead and interruption time.” Self-Organizing Networks (SON) in 3GPP A Self-Organizing Network (SON) is an automation technology designed to make the planning, configuration, management, optimization and healing of mobile radio access networks simpler and faster. SON functionality and behavior has been defined and specified in generally accepted mobile industry recommendations produced by organizations such as 3GPP and the NGMN (Next Generation Mobile Networks). In 3GPP, the processes within the SON area are classified into Self-configuration process and Self- optimization process. Self-configuration process is the process where newly deployed nodes are configured by automatic installation procedures to get the necessary basic configuration for system operation. This process works in pre-operational state. Pre-operational state is understood as the state from when the eNB is powered up and has backbone connectivity until the Radio Frequency (RF) transmitter is switched on. Figure 1 illustrates functions handled by an eNB in the pre-operational state and the operational state. Figure 1 is taken from 3GPP TS 36.300 version 17.5.0 figure 22.1-1. As illustrated in Figure 1, functions handled in the pre-operational state like: ^ Basic Setup; and ^ Initial Radio Configuration. are covered by the Self Configuration process. Self-optimization process is defined as the process where UE and access node measurements and performance measurements are used to auto-tune the network. The self-optimization process takes place in the operational state. The operational state is understood as the state where the RF interface is additionally switched on. As shown in Figure 1, functions handled in the operational state like: - Optimization / Adaptation are covered by the Self Optimization process. In Long Term Evolution (LTE), support for Self-Configuration and Self-Optimisation is specified, as described in 3GPP Technical Specification (TS) 36.300 version 17.5.0 section 22.2, including features such as Dynamic configuration, Automatic Neighbour Relation (ANR), Mobility load balancing, Mobility Robustness Optimization (MRO), Random Access Channel (RACH) optimization and support for energy saving. In NR, support for Self-Configuration and Self-Optimisation is specified as well, starting with Self- Configuration features such as Dynamic configuration, Automatic Neighbour Relation (ANR) in Rel- 15, as described in 3GPP TS 38.300 version 17.5.0 section 15. In NR Rel-16, more SON features are being specified for, including Self-Optimisation features such as Mobility Robustness Optimization (MRO). Mobility Robustness Optimization (MRO) in 3GPP Seamless handovers are a key feature of 3GPP technologies. Successful handovers ensure that the UE moves around in the coverage area of different cells without causing too many interruptions in the data transmission. However, there will be scenarios when the network fails to handover the UE to the ‘correct’ neighbor cell in time and in such scenarios the UE will declare the radio link failure (RLF) or Handover Failure (HOF). Upon HOF and RLF, the UE may take autonomous actions e.g., trying to select a cell and initiate reestablishment procedure so that the UE can get back to a connection as soon as it can, so that it can be reachable again. The RLF will cause a poor user experience as the RLF is declared by the UE only when it realizes that there is no reliable communication channel (radio link) available between itself and the network. Also, reestablishing the connection requires signaling with the newly selected cell (random access procedure, RRC Reestablishment Request, RRC Reestablishment RRC Reestablishment Complete, RRC Reconfiguration and RRC Reconfiguration Complete) and adds some latency, until the UE can exchange data with the network again. According to the specifications (3GPP TS 36.331 version 17.5.0), the possible causes for the radio link failure could be one of the following: 1) Expiry of the radio link monitoring related timer T310; 2) Expiry of the measurement reporting associated timer T312 (not receiving the handover command from the network within this timer’s duration despite sending the measurement report when T310 was running); 3) Upon reaching the maximum number of RLC retransmissions; 4) Upon receiving random access problem indication from the MAC entity. As RLF leads to reestablishment which degrades performance and user experience, it is in the interest of the network to understand the reasons for RLF and try to optimize mobility related parameters (e.g. trigger conditions of measurement reports) to avoid later RLFs. Before the standardization of MRO related report handling in the network, only the UE was aware of some information associated with the radio quality at the time of RLF, what is the actual reason for declaring RLF etc. For the network to identify the reason for the RLF, the network needs more information, both from the UE and also from the neighboring base stations. As part of the MRO solution in LTE, the RLF reporting procedure was introduced in the RRC specification in Rel-9 RAN2 work. That has impacted the RRC specifications (3GPP TS 36.331 version 17.5.0) in the sense that it was standardized that the UE would log relevant information at the moment of an RLF and later report to a target cell when the UE succeeds to connect (e.g. after reestablishment). That has also impacted the inter-gNodeB interface, i.e., X2AP specifications (3GPP TS 36.423 version 17.5.0), as an eNodeB receiving an RLF report could forward to the eNodeB where the failure has been originated. For the RLF report generated by the UE, its contents have been enhanced with more details in the subsequent releases. The measurements included in the measurement report based on the latest LTE RRC specification TS 36.331 v 18.1.0 are: 1) Measurement quantities (Reference Signal Receive Power (RSRP), Reference Signal Received Quality (RSRQ)) of the last serving cell (PCell). 2) Measurement quantities of the neighbor cells in different frequencies of different radio access technologies (RATs) (EUTRA, UTRA, GERAN, CDMA2000). 3) Measurement quantity (Received Signal Strength Indicator (RSSI)) associated to WLAN Aps. 4) Measurement quantity (RSSI) associated to Bluetooth beacons. 5) Location information, if available (including location coordinates and velocity) 6) Globally unique identity of the last serving cell, if available, otherwise the PCI and the carrier frequency of the last serving cell. 7) Tracking area code of the PCell. 8) Time elapsed since the last reception of the ‘Handover command’ message. 9) C-RNTI used in the previous serving cell. 10) Whether or not the UE was configured with a Data Radio Bearer (DRB) having Quality of Service class identifier (QCI) value of 1. After the RLF is declared, the RLF report is logged and include in the VarRLF-Report and, once the UE selects a cell and succeeds with a reestablishment, it includes an indication that it has an RLF report available in the RRC Reestablishment Complete message, to make the target cell aware of that availability. Then, upon receiving an UEInformationRequest message with a flag “rlf-ReportReq-r9” the UE shall include the RLF report (stored in a UE variable VarRLF-Report, as described above) in an UEInformationResponse message and send to the network. Based on the RLF report from the UE and the knowledge about with which cell the UE reestablished itself, the original source cell can deduce whether the RLF was caused due to a coverage hole or due to handover associated parameter configurations. If the RLF was deemed to be due to handover associated parameter configurations, the original serving cell can further classify the handover related failure as too-early, too-late or handover to wrong cell classes. These handover failure classes are now explained in brief. 1) Whether the handover failure occurred due to the ‘too-late handover / mobility’ cases a. The original serving cell can classify a handover failure to be ‘too late handover / mobility’ when the original serving cell fails to send the handover command to the UE associated to a handover towards a particular target cell and if the UE reestablishes itself in this target cell post RLF. b. An example corrective action from the original serving cell could be to initiate the handover procedure towards this target cell a bit earlier by decreasing the CIO (cell individual offset) towards the target cell that controls when the IE sends the event triggered measurement report that leads to taking the handover decision. 2) Whether the handover failure occurred due to the ‘too-early handover / mobility’ cases a. The original serving cell can classify a handover failure to be ‘too early handover / mobility’ when the original serving cell is successful in sending the handover command to the UE associated to a handover however the UE fails to perform the random access towards this target cell or the UE declares RLF in the target cell soon afterwards. b. An example corrective action from the original serving cell could be to initiate the handover procedure towards this target cell a bit later by increasing the CIO (cell individual offset) towards the target cell that controls when the IE sends the event triggered measurement report that leads to taking the handover decision. 3) Whether the handover failure occurred due to the ‘handover / mobility-to-wrong-cell’ cases a. The original serving cell can classify a handover failure to be ‘handover / mobility-to- wrong-cell’ when the original serving cell intends to perform the handover for this UE towards a particular target cell but the UE declares failure or declares failure shortly after successfully completing the handover and then reestablishes itself in a third cell. b. A corrective action from the original serving cell could be to initiate the measurement reporting procedure that leads to handover towards the target cell a bit later by decreasing the CIO (cell individual offset) towards the target cell or via initiating the handover towards the cell in which the UE reestablished a bit earlier by increasing the CIO towards the reestablishment cell. Random access report content determination Logging of a Random Access report (RA-report) by the UE upon performing an RA procedure has been specified from Rel-16 and then enhanced in Rel-17 for the 2-step RA procedure. The following is an extract from 3GPP TS 38.331 v 17.5.0. “ 5.7.10.4 Actions upon successful completion of a random-access procedure or on completion of a request of on-demand system information Upon successfully performing random-access procedure initialized with 4-step or 2-step RA type, or upon failed or successfully completed on-demand system information acquisition procedure in RRC_IDLE or RRC_INACTIVE state, the UE shall: 1> if the RPLMN or the PLMN selected by upper layers (see TS24.501) from the PLMN(s) included in the plmn-IdentityList in SIB1 is not included in plmn-IdentityList stored in a non- empty VarRA-Report: 2> clear the information included in VarRA-Report; 1> if the number of RA-Report entries stored in the ra-ReportList in VarRA-Report is less than maxRAReport: 2> if the number of PLMN entries in plmn-IdentityList stored in VarRA-Report is less than maxPLMN; or 2> if the number of PLMN entries in plmn-IdentityList stored in VarRA-Report is equal to maxPLMN and the list of EPLMNs is subset of or equal to the plmn-IdentityList stored in VarRA-Report: 3> append the following contents associated to the successfully completed random-access procedure or the failed or successfully completed on-demand system information acquisition procedure as a new entry in the VarRA-Report: 4> if the list of EPLMNs has been stored by the UE: 5> set the plmn-IdentityList to include the list of EPLMNs stored by the UE (i.e. includes the RPLMN) without exceeding the limit of maxPLMN; 4> else: 5> set the plmn-Identity, in plmn-IdentityList, to the PLMN selected by upper layers (see TS 24.501) from the PLMN(s) included in the plmn-IdentityInfoList in SIB1; 4> set the cellId to the global cell identity and the tracking area code, if available, otherwise to the physical cell identity and carrier frequency of the cell in which the corresponding random-access preamble was transmitted; 4> if the UE supports spCell ID indication: 5> if the corresponding random-access procedure was performed on an SCell of MCG: 6> set the spCellId to the global cell identity of the PCell; 5> if the corresponding random-access procedure was performed on an SCell of SCG; or 5> if the corresponding random-access procedure was performed on PSCell: 6> set the spCellId to the global cell identity of the PSCell, if available, otherwise, set the spCellId to the global cell identity of the PCell; 4> set the raPurpose to include the purpose of triggering the random-access procedure; 4> set the ra-InformationCommon as specified in clause 5.7.10.5. The UE may discard the random access report information, i.e. release the UE variable VarRA-Report, 48 hours after the last successful random access procedure or the failed or successfully completed on- demand system information acquisition procedure related information is added to the VarRA-Report. NOTE 1: The UE does not log the RA information in the RA report if the triggering event of the random access is consistent UL LBT on SpCell as specified in TS 38.321. 5.7.10.5 RA information determination The UE shall set the content in ra-InformationCommon as follows: 1> set the absoluteFrequencyPointA to indicate the absolute frequency of the reference resource block associated to the random-access resources used in the random-access procedure; 1> set the locationAndBandwidth and subcarrierSpacing associated to the UL BWP of the random-access resources used in the random-access procedure; 1> if contention based random-access resources are used in the random-access procedure: 2> set the msgA_RO-FrequencyStart and msgA-RO-FDM and msgA-SubcarrierSpacing associated to the 2 step random- access resources if used in the random-access procedure; 2> if msgA-SubcarrierSpacing associated to the 2 step random-access resources used in the random-access procedure is available: 3> set the msgA-SubcarrierSpacing associated to the 2 step random-access resources used in the random-access procedure; 2> else if only 2 step random-access resources are available in the UL BWP used in the random-access procedure: 3> set the msgA-SCS-From-prach-ConfigurationIndex to the subcarrier spacing as derived from the msgA-PRACH-ConfigurationIndex used in the 2-step random-access procedure; 2> else: 3> set the msg1-SubcarrierSpacing associated to the 4 step random-access resources used in the random-access procedure; 2> set the msg1-FrequencyStart associated to the 4 step random-access resources if used in the random-access procedure, and if its value is different from the value of msgA-RO- FrequencyStart if it is included in the ra-InformationCommon; 2> set the msg1-FDM associated to the 4 step random-access resources if used in the random- access procedure, and if its value is different from the value of msgA-RO-FDMCFRA if it is included in the ra-InformationCommon; 2> if msg1-SubcarrierSpacing associated to the 4 step random-access resources used in the random-access procedure is available, and if its value is different from the value of msgA- SubcarrierSpacing if it is included in the ra-InformationCommon: 3> set the msg1-SubcarrierSpacing associated to the 4 step random-access resources used in the random-access procedure; 2> else: 3> set the msg1-SCS-From-prach-ConfigurationIndex to the subcarrier spacing as derived from the prach-ConfigurationIndex used in the 4-step random-access procedure, and if its value is different from the value of msgA-SCS-From-prach-ConfigurationIndex if it is included in the ra-InformationCommon; 1> if contention free random-access resources are used in the random-access procedure: 2> set the msg1-FrequencyStartCFRA and msg1-FDMCFRA associated to the 4 step random- access resources if used in the random-access procedure; 2> if msg1-SubcarrierSpacing associated to the 4 step random-access resources used in the random-access procedure is available: 3> set the msg1-SubcarrierSpacingCFRA associated to the 4 step random-access resources used in the random-access procedure; 2> else: 3> set the msg1-SCS-From-prach-ConfigurationIndexCFRA to the subcarrier spacing as derived from the prach-ConfigurationIndex used in the 4 step random-access procedure; 2> set the msgA-RO-FrequencyStartCFRA and msgA-RO-FDMCFRA associated to the 2 step contention free random access resources if used in the random-access procedure; 2> set the msgA-MCS, the nrofPRBs-PerMsgA-PO, the msgA-PUSCH-TimeDomainAllocation, the frequencyStartMsgA-PUSCH, the nrofMsgA-PO-FDM associated to the 2 step random- access resources if used in the random-access procedure; 2> if msgA-SubcarrierSpacing associated to the 2 step random-access resources used in the random-access procedure is available: 3> set the msgA-SubcarrierSpacing associated to the 2 step random-access resources used in the random-access procedure; 2> else if only 2 step random-access resources are available in the UL BWP used in the random-access procedure: 3> set the msgA-SCS-From-prach-ConfigurationIndex to the subcarrier spacing as derived from the msgA-PRACH-ConfigurationIndex used in the 2-step random-access procedure; 2> else: 3> set the msg1-SubcarrierSpacing associated to the 4 step random-access resources used in the random-access procedure; > if the random access procedure is initialized with RA_TYPE set to 2-stepRA as described in TS 38.321: 2> set the dlPathlossRSRP to the measeured RSRP of the DL pathloss reference obtained at the time of RA_Type selection stage of the initialization of the RA procedure as captured in TS 38.321; 2> if the configuration for the random access msgA-TransMax was configured in RACH- ConfigDedicated for this random access procedure, and ra-Purpose is set to reconfigurationWithSync: 3> set msgA-TransMax to the value of msgA-TransMax in RACH-ConfigDedicated; 2> else if msgA-TransMax was configured in RACH-ConfigCommonTwoStepRA: 3> set msgA-TransMax to the value of msgA-TransMax in RACH- ConfigCommonTwoStepRA; 2> set the msgA-PUSCH-PayloadSize to the size of the overall payload available in the UE buffer at the time of initiating the 2 step RA procedure; > if the purpose of the random access procedure is to request on-demand system information (i.e., if the raPurpose is set to requestForOtherSI or msg3RequestForOtherSI): 2> set the intendedSIBs to indicate the SIB(s) the UE wanted to receive as a result of the SI request; 2> set the ssbsForSI-Acquisition to indicate the SSB(s) used to receive the SI message; 2> if the on-demand system information acquisition was successful: 3> set the onDemandSISuccess to true; > set the parameters associated to individual random-access attempt in the chronological order of attempts in the perRAInfoList as follows: 2> if the random-access resource used is associated to a SS / PBCH block, set the associated random-access parameters for the successive random-access attempts associated to the same SS / PBCH block for one or more random-access attempts as follows: 3> set the ssb-Index to include the SS / PBCH block index associated to the used random- access resource; 3> set the numberOfPreamblesSentOnSSB to indicate the number of successive random- access attempts associated to the SS / PBCH block; 3> for each random-access attempt performed on the random-access resource, include the following parameters in the chronological order of the random-access attempt: 4> if the random-access attempt is performed on the contention based random-access resource and if raPurpose is not equal to 'requestForOtherSI', include contentionDetected as follows: 5> if contention resolution was not successful as specified in TS 38.321 for the transmitted preamble: 6> set the contentionDetected to true; 5> else: 6> set the contentionDetected to false; 4> if the random access attempt is a 2-step random access attempt: 5> if fallback from 2-step random access to 4-step random access occurred during the random access attempt: 6> set fallbackToFourStepRA to true; 4> if the random-access attempt is performed on the contention based random-access resource; or 4> if the random-access attempt is performed on the contention free random-access resource and if the random-access procedure was initiated due to the PDCCH ordering: 5> if the random access attempt is a 4-step random access attempt and the SS / PBCH block RSRP of the SS / PBCH block corresponding to the random-access resource used in the random-access attempt is above rsrp-ThresholdSSB; or 5> if the random access attempt is a 2-step random access attempt and the SS / PBCH block RSRP of the SS / PBCH block corresponding to the random-access resource used in the random-access attempt is above msgA-RSRP-ThresholdSSB: 6> set the dlRSRPAboveThreshold to true; 5> else: 6> set the dlRSRPAboveThreshold to false; 2> else if the random-access resource used is associated to a CSI-RS, set the associated random-access parameters for the successive random-access attempts associated to the same CSI-RS for one or more random-access attempts as follows: 3> set the csi-RS-Index to include the CSI-RS index associated to the used random-access resource; 3> set the numberOfPreamblesSentOnCSI-RS to indicate the number of successive random- access attempts associated to the CSI-RS. NOTE 1: Void. RA-ReportList-r16 ::= SEQUENCE (SIZE (1..maxRAReport-r16)) OF RA-Report-r16 RA-Report-r16 ::= SEQUENCE { cellId-r16 CHOICE { cellGlobalId-r16 CGI-Info-Logging-r16, pci-arfcn-r16 PCI-ARFCN-NR-r16 }, ra-InformationCommon-r16 RA-InformationCommon-r16 OPTIONAL, raPurpose-r16 ENUMERATED {accessRelated, beamFailureRecovery, reconfigurationWithSync, ulUnSynchronized, schedulingRequestFailure, noPUCCHResourceAvailable, requestForOtherSI, msg3RequestForOtherSI- r17, spare8, spare7, spare6, spare5, spare4, spare3, spare2, spare1}, ..., [[ spCellID-r17 CGI-Info-Logging-r16 OPTIONAL ]] } RA-InformationCommon-r16 ::= SEQUENCE { absoluteFrequencyPointA-r16 ARFCN-ValueNR, locationAndBandwidth-r16 INTEGER (0..37949), subcarrierSpacing-r16 SubcarrierSpacing, msg1-FrequencyStart-r16 INTEGER (0..maxNrofPhysicalResourceBlocks-1) OPTIONAL, msg1-FrequencyStartCFRA-r16 INTEGER (0..maxNrofPhysicalResourceBlocks-1) OPTIONAL, msg1-SubcarrierSpacing-r16 SubcarrierSpacing OPTIONAL, msg1-SubcarrierSpacingCFRA-r16 SubcarrierSpacing OPTIONAL, msg1-FDM-r16 ENUMERATED {one, two, four, eight} OPTIONAL, msg1-FDMCFRA-r16 ENUMERATED {one, two, four, eight} OPTIONAL, perRAInfoList-r16 PerRAInfoList-r16, ..., [[ perRAInfoList-v1660 PerRAInfoList-v1660 OPTIONAL ]], [[ msg1-SCS-From-prach-ConfigurationIndex-r16 ENUMERATED {kHz1dot25, kHz5, spare2, spare1} OPTIONAL ]], [[ msg1-SCS-From-prach-ConfigurationIndexCFRA-r16 ENUMERATED {kHz1dot25, kHz5, spare2, spare1} OPTIONAL ]], [[ msgA-RO-FrequencyStart-r17 INTEGER (0..maxNrofPhysicalResourceBlocks-1) OPTIONAL, msgA-RO-FrequencyStartCFRA-r17 INTEGER (0..maxNrofPhysicalResourceBlocks-1) OPTIONAL, msgA-SubcarrierSpacing-r17 SubcarrierSpacing OPTIONAL, msgA-RO-FDM-r17 ENUMERATED {one, two, four, eight} OPTIONAL, msgA-RO-FDMCFRA-r17 ENUMERATED {one, two, four, eight} OPTIONAL, msgA-SCS-From-prach-ConfigurationIndex-r17 ENUMERATED {kHz1dot25, kHz5, spare2, spare1} OPTIONAL, msgA-TransMax-r17 ENUMERATED {n1, n2, n4, n6, n8, n10, n20, n50, n100, n200} OPTIONAL, msgA-MCS-r17 INTEGER (0..15) OPTIONAL, nrofPRBs-PerMsgA-PO-r17 INTEGER (1..32) OPTIONAL, msgA-PUSCH-TimeDomainAllocation-r17 INTEGER (1..maxNrofUL-Allocations) OPTIONAL, frequencyStartMsgA-PUSCH-r17 INTEGER (0..maxNrofPhysicalResourceBlocks-1) OPTIONAL, nrofMsgA-PO-FDM-r17 ENUMERATED {one, two, four, eight} OPTIONAL, dlPathlossRSRP-r17 RSRP-Range OPTIONAL, intendedSIBs-r17 SEQUENCE (SIZE (1..maxSIB)) OF SIB-Type-r17 OPTIONAL, ssbsForSI-Acquisition-r17 SEQUENCE (SIZE (1..maxNrofSSBs- r16)) OF SSB-Index OPTIONAL, msgA-PUSCH-PayloadSize-r17 BIT STRING (SIZE (5)) OPTIONAL, onDemandSISuccess-r17 ENUMERATED {true} OPTIONAL ]] } PerRAInfoList-r16 ::= SEQUENCE (SIZE (1..200)) OF PerRAInfo-r16 PerRAInfoList-v1660 ::= SEQUENCE (SIZE (1..200)) OF PerRACSI-RSInfo-v1660 PerRAInfo-r16 ::= CHOICE { perRASSBInfoList-r16 PerRASSBInfo-r16, perRACSI-RSInfoList-r16 PerRACSI-RSInfo-r16 } PerRASSBInfo-r16 ::= SEQUENCE { ssb-Index-r16 SSB-Index, numberOfPreamblesSentOnSSB-r16 INTEGER (1..200), perRAAttemptInfoList-r16 PerRAAttemptInfoList-r16 } PerRACSI-RSInfo-r16 ::= SEQUENCE { csi-RS-Index-r16 CSI-RS-Index, numberOfPreamblesSentOnCSI-RS-r16 INTEGER (1..200) } PerRACSI-RSInfo-v1660 ::= SEQUENCE { csi-RS-Index-v1660 INTEGER (1..96) OPTIONAL } PerRAAttemptInfoList-r16 ::= SEQUENCE (SIZE (1..200)) OF PerRAAttemptInfo-r16 PerRAAttemptInfo-r16 ::= SEQUENCE { contentionDetected-r16 BOOLEAN OPTIONAL, dlRSRPAboveThreshold-r16 BOOLEAN OPTIONAL, ..., [[ fallbackToFourStepRA-r17 ENUMERATED {true} OPTIONAL ]] }

[0002] RA-Report field descriptions cellID This field indicates the CGI of the cell in which the associated random access procedure was performed. contentionDetected This field is used to indicate that contention was detected for the transmitted preamble in the given random access attempt or not. This field is not included when the UE performs random access attempt is using contention free random-access resources or when the raPurpose is set to requestForOtherSI or when the RA attempt is a 2-step RA attempt and fallback to 4-step RA did not occur (i.e. fallbackToFourStepRA is not included). csi-RS-Index, csi-RS-Index-v1660 This field is used to indicate the CSI-RS index corresponding to the random access attempt. If the random access procedure is for beam failure recovery, the field indicates the NZP- CSI-RS-ResourceId. For CSI-RS index larger than maxNrofCSI-RS-ResourcesRRM-1, the index value is the sum of csi-RS-Index (without suffix) and csi-RS-Index-v1660. dlPathlossRSRP Measeured RSRP of the DL pathloss reference obtained at the time of RA_Type selection stage of the RA procedure as captured in TS 38.321 [3]. dlRSRPAboveThreshold In 4 step random access procedure, this field is used to indicate whether the DL beam (SSB) quality associated to the random access attempt was above or below the threshold rsrp-ThresholdSSB in beamFailureRecoveryConfig in UL BWP configuration of UL BWP selected for random access procedure initiated for beam failure recovery; Otherwise, rsrp- ThresholdSSB in rach-ConfigCommon in UL BWP configuration of UL BWP selected for random access procedure. In 2 step random access procedure, this field is used to indicate whether the DL beam (SSB) quality associated to the random access attempt was above or below the threshold msgA-RSRP-ThresholdSSB in rach-ConfigCommonTwoStepRA in UL BWP configuration of UL BWP selected for random access procedure. fallbackToFourStepRA This field indicates if a fallback indication in MsgB is received (according to TS 38.321 [3]) for the 2-step random access attempt. intendedSIBs This field indicates the SIB(s) the UE wanted to receive as a result of the on demand SI request (when the RA procedure is a used as a SI request) initiated by the UE. That is, it indicates the one(s) of the SIB(s) in the SI message(s) requested to be broadcast that the UE was interested in. msg1-SCS-From-prach-ConfigurationIndex This field is set by the UE with the corresponding SCS for CBRA as derived from the prach- ConfigurationIndex in RACH-ConfigGeneric when the msg1-SubcarrierSpacing is absent; otherwise, this field is absent. msg1-SCS-From-prach-ConfigurationIndexCFRA This field is set by the UE with the corresponding SCS for CFRA as derived from the prach- ConfigurationIndex in RACH-ConfigGeneric when the msg1-SubcarrierSpacing is absent; otherwise, this field is absent. msgA-PUSCH-PayloadSize This field indicates the size of the overall payload available in the UE buffer at the time of initiating the 2 step RA procedure. The value refers to the index of TS 38.321 [3], table 6.1.3.1-1, corresponding to the UE buffer size. msgA-RO-FDM This field indicates the number of msgA PRACH transmission occasions Frequency-Division Multiplexed in one time instance for the PRACH resources configured for 2-step CBRA.. msgA-RO-FDMCFRA This field indicates the number of msgA PRACH transmission occasions Frequency-Division Multiplexed in one time instance for the PRACH resources configured for 2-step CFRA. msgA-RO-FrequencyStart This field indicates the lowest resource block of the contention based random-access resources for 2-step CBRA in the random-access procedure. The indication has the form of the offset of the lowest PRACH transmissions occasion with respect to PRB 0 in the frequency domain. msgA-RO-FrequencyStartCFRA This field indicates the lowest resource block of the contention free random-access resources for the 2-step CFRA in the random-access procedure. The indication has the form of the offset of the lowest PRACH transmissions occasion with respect to PRB 0 in the frequency domain. msgA-SCS-From-prach-ConfigurationIndex This field is set by the UE with the corresponding SCS as derived from the msgA-PRACH- ConfigurationIndex in RACH-ConfigGenericTwoStepRA (see tables Table 6.3.3.1-1, Table 6.3.3.1-2, Table 6.3.3.2-2 and Table 6.3.3.2-3, TS 38.211

[0016] ) when the msgA- SubcarrierSpacing is absent and when only 2-step random-access resources are available in the UL BWP used in the random-access procedure; otherwise, this field is absent. numberOfPreamblesSentOnCSI-RS This field is used to indicate the total number of successive RA preambles that were transmitted on the corresponding CSI-RS. numberOfPreamblesSentOnSSB This field is used to indicate the total number of successive RA preambles that were transmitted on the corresponding SS / PBCH block. onDemandSISuccess This field is set to true when the RA report entry is included because of either msg1 based on demand SI request or msg3 based on demand SI request and if the on-demand SI request is successful. Otherwise, the field is absent. perRAAttemptInfoList This field provides detailed information about a random access attempt. perRACSI-RSInfoList This field provides detailed information about the successive random access attempts associated to the same CSI-RS. perRASSBInfoList This field provides detailed information about the successive random access attempts associated to the same SS / PBCH block. ra-InformationCommon This field is used to provide information on random access attempts. This field is mandatory present.

[0003] raPurpose This field is used to indicate the RA scenario for which the RA report entry is triggered. The RA accesses associated to Initial access from RRC_IDLE, RRC re- establishment procedure, transition from RRC-INACTIVE. The indicator beamFailureRecovery is used in case of successful beam failure recovery related RA procedure in the SpCell [3]. The indicator reconfigurationWithSync is used if the UE executes a reconfiguration with sync. The indicator ulUnSynchronized is used if the random access procedure is initiated in a SpCell by DL or UL data arrival during RRC_CONNECTED when the timeAlignmentTimer is not running in the PTAG or if the RA procedure is initiated in a serving cell by a PDCCH order [3]. The indicator schedulingRequestFailure is used in case of SR failures [3]. The indicator noPUCCHResourceAvailable is used when the UE has no valid SR PUCCH resources configured [3]. The indicator requestForOtherSI is used for MSG1 based on demand SI request. The indicator msg3RequestForOtherSI is used in case of MSG3 based SI request. The field can also be used for the SCG-related RA-Report when the raPurpose is set to beamFailureRecovery, reconfigurationWithSync, ulUnSynchronized, schedulingRequestFailure and noPUCCHResourceAvailable. spCellID This field is used to indicate the CGI of the SpCell of the cell group associated to the SCell in which the associated random access procedure was performed. If the UE performs RA procedure on a SCell associated to the MCG, then this field is set to the CGI of the PCell and if the UE performs RA procedure on a SCell associated to the SCG, then this field is set to the CGI of the PSCell. If the CGI of the PSCell is not available at the UE for the RA procedure performed on a SCell associated to the SCG or for the RA procedure on the PSCell, this field is set to the CGI of the PCell. Otherwise, the field is absent. ssb-Index This field is used to indicate the SS / PBCH index of the SS / PBCH block corresponding to the random access attempt. ssbsForSI-Acquisition This field indicates the SSB(s) (in the form of SSB index(es)) that the UE used to receive the requested SI message(s). The field is present if the purpose of the random access procedure was to request on-demand SI (i.e. if the raPurpose is set to requestForOtherSI or msg3RequestForOtherSI). Otherwise, the field is absent. ” SUMMARY There currently exist certain challenge(s). For L1 / L2 based inter-cell mobility (e.g., see RP-211586, 3GPP work item description: Further enhancements on MIMO for NR, Samsung, 3GPP TSG RAN Meeting #92e, Electronic Meeting, June 14-18, 2021 ), the overall procedure and signaling is still open. A goal of L1 / L2 based inter-cell mobility is to reduce latency, overhead and interruption time during the actual cell switching mechanism. The L1 / L2 inter-cell mobility decisions are taken by the source Distributed Unit (DU) in comparison with the legacy L3 mobility decisions which were taken by the source Centralized Unit Control Plane (CU-CP). The L1 / L2 inter-cell mobility candidates are expected to be configured in a UE specific way. A UE might have limitations on how many inter-cell mobility candidates it can keep in the memory (e.g., 8 L1 / L2 inter-cell mobility candidates) and thus different UEs in the same DU might be configured with different candidate L1 / L2 inter-cell mobility candidates depending on the UE’s location, mobility characteristics and other parameters. The following agreements were made in the 3GPP meeting RAN1#122-bis, providing the main pillars in designing the RACH based LTM cell switch mechanism. ^ For Physical Downlink Control Channel (PDCCH) ordered-RACH, if reception of a random access response (RAR) is not configured, UE autonomous re-transmission of PRACH is not allowed, regardless of the configuration of PreambleTransMax. ^ For PDCCH ordered-RACH, if reception of RAR is not configured, Whether power ramping is performed or not is determined from PDCCH order ^ If power ramping is performed ^ whether PRACH is an initial transmission or retransmission is explicitly indicated in PDCCH order (FFS exact indication mechanism). ^ power ramping-up value is configured ^ else, the power should be determined by open-loop power control ^ For PDCCH ordered RACH mechanism in Release 18 (R18) LTM, when reception of RAR is configured, ^ the UE stores(remembers / maintains / handles) a Timing Advancce (TA) for at least one candidate cell ^ storing(remembering / maintaining / handling) corresponding TAs for more than one candidate cell is up to UE capability The agreements define new requirements on how the UE shall perform a random-access procedure for a LTM cell switch mechanism. Some differences are: ^ RA procedure can be ordered by the PDCCH to be performed toward an LTM candidate cell i.e., other than serving cell. ^ Receiving RAR from the source cell is configurable ^ when reception of RAR from the source cell is not configured, whether power ramping is allowed or not is configurable, ^ It is up to UE to store the Timing Advance (TA) of the candidate cells (at least TA of one candidate cell should be stored) Considering the above differences between the RA procedure performed for the LTM cell switch and the legacy / regular RA procedure (RA procedure performed for the normal reconfiguration with sync procedure), enhancement of the data collection for RA procedure (e.g., RA report) is needed. For example, based on the existing RA-report, there is no implicit or explicit mean to deduce whether a RA procedure is performed for an LTM cell switch (or for other purposes). In addition, it is not possible for the network to deduce from the RA report whether the RA procedure is performed based on the received cell switch command (RACH based cell switch) or due to the fallback from RACH-less cell switch command to the RACH-based cell switch (e.g., when the UE fails to complete the RACH-less cell switch and performs a random access procedure toward a candidate cell due to the failure of the RACH-less LTM cell switch procedure). Certain aspects of the disclosure and their embodiments may provide solutions to these or other challenges. The present disclosure comprises an enhancement to the information collected, stored and / or reported by a UE after or during a RA procedure for an LTM cell switch. For example, the UE may collect, store and / or report information associated with the RA procedure for the LTM cell switch such as an indication that a purpose of the RA procedure is an LTM cell switch operation. This information may enable a network node to analyze the performance of the RA procedures performed as part of the LTM cell switch procedure. The information may be included, for example, in one or more of: an RA report; a radio link failure report; a successful handover report (SHR); a successful PSCell change report (SPR); an UEInformationResponse message; an SCGFailureInformation message; or an MCGFailureInformation message. For example, an RA report may be enhanced with an indication that the RA procedure is performed for the purpose of an LTM cell switch mechanism. Thus, the present disclosure may comprise an enhancement to RA reporting (e.g., the RA report) with indications and / or information that enables a network node (e.g., RAN node) to analyze the performance of RA procedures performed as part of the LTM cell switch procedure, e.g., based on the received RA report logged and reported by the UE. The present disclosure may further enable a better power analysis during the RA procedure e.g., the reconstruction of the power level used in a preamble transmission attempt. As used herein, a RA procedure for LTM may comprise one or more steps of a RA procedure such as preamble transmission, reception of a TA command, reception of a trigger for preamble re-transmission (e.g. PDCCH order), preamble re-transmission, etc. The RA procedure may comprise the UE receiving a trigger for LTM cell switch. For example, while the UE is connected to a source cell, the UE receives an LTM cell switch command to change from the source cell to an LTM candidate cell (e.g. Medium Access Control (MAC) control element (CE) including an LTM candidate configuration identifier), and in response the UE transmits a preamble to an LTM candidate cell e.g. in case the UE does not have TA established. In some embodiments, the UE may trigger a random access procedure during LTM cell switch based on an indication of an LTM candidate cell configuration for an LTM candidate cell indicated in the LTM cell switch command. For example, the LTM cell switch command may include an LTM candidate ID which points to an LTM candidate cell configuration which includes that the LTM cell switch is to be based on random access. In some embodiments, the UE may trigger a random access procedure during LTM cell switch based on an indication in the LTM cell switch command, e.g., the presence or absence of a field in the LTM cell switch MAC CE. For example, there may be a particular value for the Timing Advance which indicates to the UE that random access is to be performed for the LTM cell switch procedure. In some embodiments, the UE may trigger a random access procedure during LTM cell switch based on the status of the Time Alignment timer monitored by the UE for an LTM candidate cell. The UE may perform random access to the LTM candidate cell indicated in the LTM cell switch command when the Time Alignment timer for that LTM candidate cell is expired. In some embodiments, the UE may first try to perform the LTM cell switch without RA (RACH-less LTM cell switch), and if that RACH-less LTM procedure fails (e.g. the UE detects the absence of a PDCCH transmission while a supervision timer is running), then the UE may fall back to RA procedure, and set the content of the RA report to include an indication that the random access procedure was initiated due to a failure in the RACH-less LTM cell switch procedure. For each of these cases there may be different information logged / transmitted by the UE, e.g., in the RA report. For example, a cause / purpose value for the random access procedure may be indicated e.g. random access in LTM cell switch due to RACH-less failure. According to the present disclosure there is provided a method performed by a UE. The method may comprise one or more of: ^ Receiving an indication indicating to perform an LTM mobility related procedure from the first cell to the second cell using an LTM cell switch command received from the distributed unit (DU) serving the first cell. o The command sent by the DU may include an indication / configuration(s) that instructs the UE to perform a random access procedure toward the second cell. The RA procedure might be for performing an LTM cell switch procedure. In some embodiments, the RA procedure might even be due to a failure of performing a RACH-less LTM cell switch procedure. ^ Performing random access procedure toward the second cell, either: o Upon receiving a RACH based cell switch command e.g., from the serving DU. o Upon failure in performing a RACH-less LTM cell switch procedure. ^ Storing a first set of information (also referred to herein as first information) associated to the random-access procedure, comprising one or more of: o An indication indicating the purpose of the random-access procedure is LTM cell switch. o An indication indicating whether the RA is triggered by a DCI indication in PDCCH or via a MAC CE. o An indication indicating whether the reception of the RAR was allowed / configured in the received LTM cell switch command or not. o An indication indicating whether the reception of the RAR from source cell was allowed / configured when the UE receives the random-access configuration to be used for acquiring a TA towards a candidate cell. o An indication of the time interval (e.g. in seconds, subframes of source, subframes of LTM candidate cell, number of time domain PRACH resources, time slots, OFDM symbols, etc.) between the time instance in which the UE receives the last trigger for TA establishment from source (if such TA establishment was received) until LTM cell switch command execution (i.e., performing RACH for the LTM cell switch). ^ In an embodiment, the UE may log the time elapsed between receiving the last trigger for the TA acquisition for the candidate cell toward which the UE performed the RA procedure for the RACH based LTM cell switch procedure and the time of executing the RACH based LTM cell switch toward that candidate cell. ^ In an embodiment, the UE may log the time elapsed between receiving the last trigger for the LTM cell switch toward any candidate LTM cell and the time of executing the RACH based LTM cell switch toward a candidate cell. o An indication indicating whether the LTM cell switch command includes the timing advance information or not. o An indication indicating whether the UE stored the TA received from the serving cell for the candidate cell toward which the LTM cell switch was performed or not. o An indication, indicating whether there is any difference between the TA the UE received from the serving cell and the TA UE received as part of the RA response message o An indication indicating the difference between the TA that UE received from the serving cell and the TA that UE received in the random access response message. o An indication indicating the TA that UE acquired as part of the RA procedure performed for the RACH based LTM cell switch purpose. o This indication may be useful for the network to verify the difference between the acquired TA from the neighboring / candidate cells. o An indication indicating whether the RA procedure was triggered due to failure in performing RACH-less LTM cell switch e.g., when the TA is provided in the LTM cell switch command and applied by the UE for switching to the target cell / beam. ^ Logging the above information concerning the TA may be valuable for the network, e.g., to determine the difference between the established TA and the TA that the UE acquired during the RA procedure for the cases in which the UE performs RA based LTM cell switch. In general, the information may enable improvement / optimization of TA acquisition procedures at the RAN nodes capable of LTM cell switch procedures. o An indication indicating the actual power level applied by the UE when transmitting the RA preamble for the LTM cell switch purpose. o An indication of the beam indicated in the DCI indication in PDCCH or in the MAC CE as the beam in which the UE is supposed to execute the random access procedure. o An indication of the best beam of the cell (e.g. beam or SSB or CSI-RS whose a quantity, such as RSRP, is the strongest) towards which the UE performs the random access procedure as measured by the UE before initiating the random access procedure, and / or at completion of the random access procedure, o Beam measurements (e.g. L1-RSRP of beams and / or SSBs, SS-RSRP values) when the UE is triggered to transmit a preamble for TA establishment and when the UE receives the LTM cell switch command. Performing a random access procedure toward the second cell may comprise the UE performing one or more steps related to random access such as one or more of: - Transmission of a preamble e.g. in case a preamble is transmitted in response to the UE receiving an LTM cell switch command; - Reception of an RA response (RAR) e.g. in case a preamble is transmitted in response to the UE receiving an LTM cell switch command; - Re-transmission of a preamble e.g. in case of not receiving a RAR within a RAR time window, when the UE transmits a preamble to an LTM candidate cell; - Reception of a TA value from the source cell either within an LTM cell switch command; - Selection of a RA resource, prior to the transmission or re-transmission of a preamble, upon reception of the LTM cell switch command; - Detection of contention in case the UE trigger RA upon reception of an LTM cell switch command. According to some embodiments there is provided a method performed by a user equipment, UE, being served by a first cell of a first network node. The method comprises performing a random access, RA, procedure for a lower-layer triggered mobility, LTM, cell switch to a second cell. The method further comprises determining first information associated with the RA procedure for the LTM cell switch to the second cell. According to some embodiments there is provided a method performed by a network node, wherein a user equipment, UE, is being served by a first cell of a first network node. The method comprises receiving, from the UE, first information associated with a random access, RA, procedure for a lower- layer triggered mobility, LTM, cell switch to a second cell. According to some embodiments there is provided a user equipment adapted to be served by a first cell of a first network node, the user equipment comprising processing and a memory. The memory contains instructions executable by the processing circuitry whereby the user equipment is operable to: perform a random access, RA, procedure for a lower-layer triggered mobility, LTM, cell switch to a second cell. The memory contains further instructions executable by the processing circuitry whereby the user equipment is operable to determine first information associated with the RA procedure for the LTM cell switch to the second cell. According to some embodiments there is provided a network node comprising processing circuitry and a memory. The memory contains instructions executable by the processing circuitry whereby the network node is operable to: receive, from a UE being served by a first cell of a first network node, first information associated with a random access, RA, procedure for a lower-layer triggered mobility, LTM, cell switch to a second cell. According to some embodiments there is provided a computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out any of the methods described above. According to some embodiments there is provided a computer-readable medium comprising instructions that, when executed on at least one processor, cause the at least one processor to perform any of methods described above. According to some embodiments there is provided a computer program product comprising non transitory computer readable media having stored thereon a computer program as described above. Certain embodiments may provide one or more of the following technical advantage(s). Based on the first information associated with an RA procedure for the LTM cell switch that is determined, stored and / or transmitted by the UE, (e.g., a new RA-purpose in the RA report), the network may identify that a random access procedure (e.g., a random access procedure associated with the collected random-access report) was performed as part of an LTM cell switch operation. Hence, the network node can correlate the random-access report to the LTM cell switch events. In addition, the network may determine whether the RACH-based LTM cell switch was initiated as fallback due to the failure of a RACH-less RA procedure. Moreover, the present disclosure enables the TA acquisition procedures at the RAN nodes (e.g., at the distributed unit) to be improved. For example, information may be collected concerning the TA value, e.g., the potential difference between the TA value already calculated at the network side and the TA value at the time of execution of the cell switch command network. BRIEF DESCRIPTION OF THE DRAWINGS For a better understanding of the embodiments of the present disclosure, and to show how it may be put into effect, reference will now be made, by way of example only, to the accompanying drawings, in which: Fig.1 depicts some ramifications of self-configuration / self-optimization functionality; Fig.2 is a flow chart illustrating a method in accordance with some embodiments; Fig.3 is a flow chart illustrating a method in accordance with some embodiments; Fig.4 is a signalling diagram illustrating an example implementation of the methods of Fig.2 and Fig. 3. Fig.5 shows an example of a communication system in accordance with some embodiments; Fig.6 shows a UE in accordance with some embodiments; Fig.7 shows a network node in accordance with some embodiments; and Fig. 8 is a block diagram illustrating a virtualization environment in which functions implemented by some embodiments may be virtualized. DETAILED DESCRIPTION Some of the embodiments contemplated herein will now be described more fully with reference to the accompanying drawings. Embodiments are provided by way of example to convey the scope of the subject matter to those skilled in the art. Figure 2 depicts a method in accordance with particular embodiments. The method of Figure 2 may be performed by a UE or wireless device (e.g. the UE 512 or UE 600 as described later with reference to Figures 5 and 6 respectively). The UE is being served by a first cell of a first network node. The method comprises, at step 202, performing a random access procedure for a lower-layer triggered mobility cell switch to a second cell. The method further comprises, at step 204, determining first information associated with the RA procedure for the LTM cell switch to the second cell. The method of Figure 2 may comprise storing or logging the first information. The method of Figure 2 may comprise transmitting, to a network node, at least some of the first information. The at least some of the first information may be transmitted in a random access report. The at least some of the first information may be transmitted in one or more of: a radio link failure report; a successful handover report; a successful PSCell change report; an UEInformationResponse message; an SCGFailureInformation message; and an MCGFailureInformation message. The first information associated with the RA procedure may comprise an indication that a purpose of the RA procedure is an LTM cell switch operation. The first information associated with the RA procedure may comprise one or more of: an indication of what triggered the UE to perform the RA procedure; an indication that the RA procedure was performed responsive to a downlink control information, DCI, indication; and an indication of a power level applied by the UE during the RA procedure. The first information may comprise information relating to one or more timing advance (TA) values associated with the RA procedure. The information relating to one or more TA values may comprise one or more of: an indication of whether a random-access configuration received by the UE and to be used for acquiring a TA for the second cell allows reception of an RA response, RAR from the first cell; an indication of a minimum time interval between the UE receiving from the first cell a trigger for TA establishment and the UE performing the RA procedure for the LTM cell switch to the second cell; an indication of whether the UE stored a TA value received from the first cell for the second cell; an indication of whether there is any difference between a TA value that the UE received from the first cell for the second cell and a TA value that the UE received as part of an RA response message during the RA procedure; an indication of a difference between a TA value that the UE received from the first cell for the second cell and a TA that the UE received as part of an RA response message during the RA procedure; an indication of a TA value for the second cell that the UE received during the RA procedure; and an indication of TA values for one or more candidate cells for cell switch. The first information may comprise an indication of at least one beam associated with the RA procedure. The indication of a beam may comprise one or more of: an indication of a beam in the second cell towards which the UE performed the RA procedure; an indication of a beam in the second cell that was indicated to the UE as a beam toward which the UE should perform the RA procedure; and an indication of a beam in the second cell selected by the UE based on beam measurements obtained before or after performing the RA procedure. The first information may comprise beam measurements associated with the RA procedure. The beam measurements may comprise one or both of: beam measurements obtained when the UE is triggered to transmit a preamble for timing advance establishment for the LTM cell switch to the second cell; and beam measurements obtained when the UE receives an LTM cell switch command to perform the RA procedure for the LTM cell switch to the second cell. The beam measurements may comprise one or more of: a signal strength value; a quality value; a cell identifier; a RSRP; a Layer-1 RSRP; a Synchronization Signal RSRP; a RSRQ; a Signal to Interference plus Noise Ratio (SINR); a beam index; a beam identifier; and a Synchronization Signal Block (SSB) index. The method of Figure 2 may further comprise performing the RA procedure responsive to receiving a first indication to perform the RA procedure for the LTM cell switch to the second cell. The first indication may comprise or be comprised in an LTM cell switch command for the LTM cell switch to the second cell. The first information may comprise information relating to the LTM cell switch command. The information relating to the LTM cell switch command may comprise one or more of: an indication of whether the LTM cell switch command allows reception of an RAR; an indication of whether the LTM cell switch command allows preamble retransmission; an indication of whether the LTM cell switch command allows power ramping; and an indication of whether the LTM cell switch command comprises timing advance information. The first indication may comprise or be comprised in one or more of: an MAC CE; a PDCCH order; and a DCI indication. The first indication may comprise one or more of: an indication of an LTM candidate cell configuration for the second cell; an indication of a beam index toward which the UE should perform the RA procedure; an LTM candidate configuration identifier; and a Timing Advance value. The first indication may be received from the first network node serving the first cell. Performing the RA procedure may comprise one or more of: transmitting an RA preamble to a second network node serving the second cell; receiving a timing advance command (TAC) for the LTM cell switch to the second cell; receiving a trigger for re-transmission of the RA preamble to the second network node serving the second cell; retransmitting the RA preamble to the second network node; receiving an RAR from the second network node; receiving a TA value from the first network node; detecting contention; and selecting an RAR. In some embodiments, the RA procedure may be successful. The network node to which at least some of the first information is transmitted may be a second network node serving the second cell. In other embodiments, the RA procedure may be unsuccessful. The network node to which the at least some of the first information is transmitted may be the first network node. In some embodiments, the first cell may be one of: a PCell for the UE; a PSCell for the UE; and a SCell for the UE. The second cell may be one or more of: a PCell for the UE; a PSCell for the UE; an SCell for the UE; a cell of the first network node; and a cell of a different network node to the first cell. The second cell may be configured by the UE as an LTM candidate target cell. The method of Figure 2 may further comprise performing the RA procedure responsive to determining that a RACH-less LTM cell switch to the second cell has failed. Determining that a RACH-less LTM cell switch to the second cell has failed may comprise determining that a supervision timer has expired without the UE receiving a Physical Downlink Control Channel (PDCCH) transmission. The method of Figure 2 may further comprise providing user data; and forwarding the user data to a host via the transmission to the network node. A complementary method performed by a network node is described with respect to Figure 3. Further detail regarding the method of Figure 2 performed by the UE is set out herein. The UE may perform the method in response to executing suitably formulated computer readable code. The computer readable code may be embodied or stored on a computer readable medium, such as a memory chip, optical disc, or other storage medium. The computer readable medium may be part of a computer program product. Figure 3 depicts a method in accordance with particular embodiments. The method of Figure 3 may be performed by a network node. The network node may be a RAN node (e.g. the network node 510 or network node 700 as described later with reference to Figures 5 and 7 respectively). According to the method 3, a user equipment is being served by a first cell of a first network node. The method comprises, at step 302, receiving, from the UE, first information associated with an RA procedure for an LTM cell switch to a second cell. The first information may be received in a random access report. The first information may be transmitted in one or more of: an RLF report; a successful handover report; a successful PSCell change report; an UEInformationResponse message; an SCGFailureInformation message; and an MCGFailureInformation message. The first information associated with the RA procedure may comprise an indication that a purpose of the RA procedure is an LTM cell switch operation. The first information associated with the RA procedure may comprise one or more of: an indication of what triggered the UE to perform the RA procedure; an indication that the RA procedure was performed responsive to a DCI indication; and an indication of a power level applied by the UE during the RA procedure. The first information may comprise information relating to one or more TA values associated with the RA procedure. The information relating to one or more TA values may comprise one or more of: an indication of whether a random-access configuration received by the UE and to be used for acquiring a TA towards the second cell allows reception of an RAR from the first cell; an indication of a minimum time interval between the UE receiving from the first cell a trigger for TA establishment, and the UE performing the RA procedure for the LTM cell switch to the second cell; an indication of whether the UE stored a TA value received from the first cell for the second cell; an indication of whether there is any difference between a TA value that the UE received from the first cell for the second cell and a TA value that the UE received as part of an RA response message during the RA procedure; an indication of a difference between a TA value that the UE received from the first cell for the second cell and a TA value that the UE received as part of an RA response message during the RA procedure; an indication of a TA value for the second cell that the UE received during the RA procedure; and an indication of TA values for one or more candidate cells for cell switch. The first information may comprise an indication of at least one beam associated with the RA procedure. The indication of at least one beam may comprise one or more of: an indication of a beam of the second cell towards which the UE performed the RA procedure; an indication of a beam of the second cell that was indicated to the UE as a beam toward which the UE should perform the RA procedure; and an indication of a beam of the second cell selected by the UE based on beam measurements obtained before or after performing the RA procedure. The first information may comprise beam measurements associated with the RA procedure. The information relating to one or more TA values may comprise one or more of: an indication of whether a random-access configuration received by the UE and to be used for acquiring a TA towards the second cell allows reception of an RAR from the first cell; an indication of a minimum time interval between the UE receiving from the first cell a trigger for TA establishment, and the UE performing the RA procedure for the LTM cell switch to the second cell; an indication of whether the UE stored a TA value received from the first cell for the second cell; an indication of whether there is any difference between a TA value that the UE received from the first cell for the second cell and a TA value that the UE received as part of an RA response message during the RA procedure; an indication of a difference between a TA value that the UE received from the first cell for the second cell and a TA value that the UE received as part of an RA response message during the RA procedure; an indication of a TA value for the second cell that the UE received during the RA procedure; and an indication of TA values for one or more candidate cells for cell switch. The first information may comprise an indication of at least one beam associated with the RA procedure. The indication of at least one beam may comprise one or more of: an indication of a beam of the second cell towards which the UE performed the RA procedure; an indication of a beam of the second cell that was indicated to the UE as a beam toward which the UE should perform the RA procedure; and an indication of a beam of the second cell selected by the UE based on beam measurements obtained before or after performing the RA procedure. The first information comprises beam measurements associated with the RA procedure. The beam measurements may comprise one or both of: beam measurements obtained when the UE is triggered to transmit a preamble for TA establishment for the LTM cell switch to the second cell; and beam measurements obtained when the UE receives an LTM cell switch command to perform the RA procedure for the LTM cell switch to the second cell. The beam measurements may comprise one or more of: a signal strength value; a quality value; a cell identifier; an RSRP; a Layer-1 RSRP; a Synchronization Signal RSRP; an RSRQ; an SINR; a beam index; a beam identifier; and an SSB index. The first information may comprise information relating to an LTM cell switch command for the LTM cell switch to the second cell. The information relating to the LTM cell switch command may comprise one or more of: an indication of whether the LTM cell switch command allows reception of an RAR; an indication of whether the LTM cell switch command allows preamble retransmission; an indication of whether the LTM cell switch command allows power ramping; and an indication of whether the LTM cell switch command comprises TA information. The method of Figure 3 may further comprise, prior to receiving the first information, performing an RA procedure with the UE for the LTM cell switch of the UE to the second cell. Performing the RA procedure may comprise one or more of: receiving an RA preamble from the UE; transmitting a TAC for the LTM cell switch to the second cell; transmitting a trigger for re-transmission of the RA preamble to the UE; receiving a retransmission of the RA preamble from the UE; and transmitting an RA response, RAR, to the UE. In some embodiments, the RA procedure may be successful. The network node may be a second network node serving the second cell. In alternative embodiments, the network node may be the first network node. The method of Figure 3 may further comprise determining, based on the first information, that the RA procedure was for an LTM cell switch. The method of Figure 3 may further comprise updating one or more TA acquisition procedures at the first network node based on the first information. The first cell may be one of: a PCell for the UE; a PSCell for the UE; and an SCell for the UE. The second cell may be one or more of: a PCell for the UE; a PSCell for the UE; an SCell for the UE; a cell of the first network node; and a cell of a different network node to the first cell. The method of Figure 3 may further comprise: obtaining user data; and forwarding the user data to a host or a user equipment. The network node may perform the method in response to executing suitably formulated computer readable code. The computer readable code may be embodied or stored on a computer readable medium, such as a memory chip, optical disc, or other storage medium. The computer readable medium may be part of a computer program product. In the present disclosure, the terms ‘LTM cell switch’ and ‘L1 / L2 mobility operation’ are used interchangeably. The present disclosure comprises a method performed by a wireless terminal (so called a user equipment (UE)). The method may comprise one or more of the following steps. ^ Receiving an indication from a distributed unit (DU) serving a serving cell (e.g., an SpCell, which can be a PCell, PSCell, or SCell) for the UE. The indication may indicate to the UE to perform an L1 / L2 mobility cell switch procedure from the serving cell to a second cell (a target cell of L1 / L2 mobility operation which can be a PCell, SPCell or SCell). o The indication may be received as part of a DCI indication in PDCCH. o The indication may be received as part of a MAC control element (so-called a MAC CE). o The command sent by the DU may include an indication / configuration that instructs the UE to perform random access procedure toward the second / target cell. ^ The configuration may include the beam (SS / PBCH block or CSI-RS) index toward which the UE should perform the random-access procedure. ^ Performing random access procedure toward the second cell based on the received configuration(s). This may comprise an example implementation of step 202 ^ Determining / storing / logging a first set of information associated to the random-access procedure (also referred to herein as ‘first information’). This step may comprise an example implementation of step 204. The first set of information may comprise the first information of step 202 or step 302. The first set of information may comprise one or more of: o An indication indicating the purpose of the random-access procedure is LTM cell switch or L1 / L2 mobility operation. ^ An indication indicating how the LTM cell switch command was received, e.g., whether the LTM cell switch command was received as part of DCI indication in PDCCH, or as a MAC CE, etc. o An indication indicating whether the reception of the RAR was allowed / configured in the received LTM cell switch command. An indication indicating whether the LTM cell switch command includes the timing advance information. An indication indicating whether the UE stored the TA received from the serving cell for the candidate cell toward which the LTM cell switch was performed. An indication indicating whether there is any difference between the TA the UE received from the serving cell and the TA UE received as part of the RA response message An indication indicating the difference between the TA that UE received from the serving cell and the TA that UE received in the random access response message. An indication indicating the TA that UE acquired as part of the RA procedure performed for the RACH based LTM cell switch purpose. This indication would be useful for the network to verify the difference between the acquired TA from the neighboring / candidate cells. An indication indicating whether the RA procedure is triggered due to failure in performing RACH less LTM cell switch i.e., when the TA is provided in the LTM cell switch command and applied by the UE for switching to the target cell / beam. An indication indicating whether the LTM cell switch command includes the timing advance (TA) information. ^ In some embodiments the UE may log the timing advance value provided in the cell switch command. One or a list / set of indications indicating the TA of the candidate cells of the cell switch procedures irrespective of how they are acquired (either as part of cell switch command or as part of RAR). ^ Logging the above information concerning the TA may allow the network to determine the difference between the established TA and the TA that the UE acquired during the RA procedure for the instances in which the UE performs RA based LTM cell switch. In general, the first set of information may enable the improvement / optimization of TA acquisition procedures at the RAN nodes that are capable of LTM cell switch procedures. An indication indicating whether the preamble re-transmission was allowed / configured in the received LTM cell switch command. An indication indicating whether the power ramping was allowed / configured in the received LTM cell switch command. An indication indicating the actual power level applied by the UE when transmitting the preamble. o An indication indicating the beam (SS / PBCH block or CSI-RS) index as indicated in the indication received from the DU for the execution of the random access procedure. o An indication indicating the beam (SS / PBCH block or CSI-RS) index of the best beam based on the last available measurements performed at the UE before the execution of the random access procedure, or after completion of the random access procedure. In some embodiments, the measurements may comprise one or more of: RSRP (if available), the RSRQ (if available), the SINR (if available), and the RSSI (if available). In some embodiments, the said indication is included only if the beam (SS / PBCH block or CSI-RS) index of the best beam differs from the beam index as indicated in the indication received from the DU for the execution of the random access procedure. Some or all of the first set of information (e.g., one or more of the indications included in the first set of information) may be included in (as an example implementation of step 302 of Figure 3) one or more of: ^ A random-access report generated by the UE. The RA report may be generated by the UE at successful completion of the random access procedure, or at failure of the random access procedure. ^ An RLF-Report. The RLF report may be generated by the UE upon detecting RLF or HOF or LTM failure. ^ A Successful HO Report (SHR) or Successful PSCell change report (SPR). The SHR or SPR may be generated by the UE at successful completion of the PCell LTM or PSCell change via LTM. ^ An SCGFailureInformation message. The SCGFailureInformation message may be generated by the UE upon SCG failure. ^ An MCGFailureInformation message. The MCGFailureInformation message may be generated by the UE upon MCG failure and / or when the UE performs fast MCG link recovery. Figure 4 is a signaling diagram illustrating an example implementation of the methods of Figures 2 and 3. The network elements involved in the signaling diagram of Figure 4 are the UE 400, which is configured to perform the method of Figure 2, the first NW node 410 and the second network node 420. In a first alternative, the first NW node 410 performs the method of Figure 3, and in a second alternative, the second NW node 420 performs the method of Figure 3. In step 401 the UE 400 is being served by a first cell of the first NW node 410. In step 402, the UE 400 performs a random access procedure for a lower-layer triggered mobility cell switch to a second cell. The second cell is served by the second NW node 420. Step 402 may be considered an example implementation of the step 202 of Figure 2. In step 403, the UE 400 determines first information associated with the RA procedure for the LTM cell switch to the second cell. Step 403 may be considered an example implementation of step 204 of Figure 2. If the random access procedure of step 402 is successful, then alternative 1 of the signalling diagram may occur. In alternative 1, the UE 400 may in some examples transmit, in step 404, at least some of the first information to the second network node 420. Step 404 may be considered an example implementation of step 302 of Figure 3. If the random access procedure of step 402 is unsuccessful, then alternative 2 of the signalling diagram may occur. In alternative 2, the UE 400 may in some examples transmit, in step 405, at least some of the first information to the first network node 410. Step 405 may be considered an example implementation of step 302 of Figure 3. A non-limiting example implementation of the present disclosure is given below (where 3GPP TS 38.331 v17.5.0 is taken as the baseline). The impact of the method on TS 38.331 v 17.5.0 is shown in bold and underlined. In this example implementation, it is considered that a subset of the information included in the first set of information is reported in the random-access report or as part of a radio link failure report. UEInformationResponse The UEInformationResponse message is used by the UE to transfer information requested by the network. Signalling radio bearer: SRB1 or SRB2 (when logged measurement information is included) RLC-SAP: AM Logical channel: DCCH Direction: UE to network UEInformationResponse message -- ASN1START -- TAG-UEINFORMATIONRESPONSE-START UEInformationResponse-r16 ::= SEQUENCE { rrc-TransactionIdentifier RRC-TransactionIdentifier, criticalExtensions CHOICE { ueInformationResponse-r16 UEInformationResponse-r16-IEs, criticalExtensionsFuture SEQUENCE {} } } UEInformationResponse-r16-IEs ::= SEQUENCE { measResultIdleEUTRA-r16 MeasResultIdleEUTRA-r16 OPTIONAL, measResultIdleNR-r16 MeasResultIdleNR-r16 OPTIONAL, logMeasReport-r16 LogMeasReport-r16 OPTIONAL, connEstFailReport-r16 ConnEstFailReport-r16 OPTIONAL, ra-ReportList-r16 RA-ReportList-r16 OPTIONAL, rlf-Report-r16 RLF-Report-r16 OPTIONAL, mobilityHistoryReport-r16 MobilityHistoryReport-r16 OPTIONAL, lateNonCriticalExtension OCTET STRING OPTIONAL, nonCriticalExtension UEInformationResponse-v1700-IEs OPTIONAL } UEInformationResponse-v1700-IEs ::= SEQUENCE { successHO-Report-r17 SuccessHO-Report-r17 OPTIONAL, connEstFailReportList-r17 ConnEstFailReportList-r17 OPTIONAL, coarseLocationInfo-r17 OCTET STRING OPTIONAL, nonCriticalExtension SEQUENCE {} OPTIONAL } LogMeasReport-r16 ::= SEQUENCE { absoluteTimeStamp-r16 AbsoluteTimeInfo-r16, traceReference-r16 TraceReference-r16, traceRecordingSessionRef-r16 OCTET STRING (SIZE (2)), tce-Id-r16 OCTET STRING (SIZE (1)), logMeasInfoList-r16 LogMeasInfoList-r16, logMeasAvailable-r16 ENUMERATED {true} OPTIONAL, logMeasAvailableBT-r16 ENUMERATED {true} OPTIONAL, logMeasAvailableWLAN-r16 ENUMERATED {true} OPTIONAL, ... } LogMeasInfoList-r16 ::= SEQUENCE (SIZE (1..maxLogMeasReport- r16)) OF LogMeasInfo-r16 LogMeasInfo-r16 ::= SEQUENCE { locationInfo-r16 LocationInfo-r16 OPTIONAL, relativeTimeStamp-r16 INTEGER (0..7200), servCellIdentity-r16 CGI-Info-Logging-r16 OPTIONAL, measResultServingCell-r16 MeasResultServingCell-r16 OPTIONAL, measResultNeighCells-r16 SEQUENCE { measResultNeighCellListNR MeasResultListLogging2NR-r16 OPTIONAL, measResultNeighCellListEUTRA MeasResultList2EUTRA-r16 OPTIONAL }, anyCellSelectionDetected-r16 ENUMERATED {true} OPTIONAL, ..., [[ inDeviceCoexDetected-r17 ENUMERATED {true} OPTIONAL ]] } ConnEstFailReport-r16 ::= SEQUENCE { measResultFailedCell-r16 MeasResultFailedCell-r16, locationInfo-r16 LocationInfo-r16 OPTIONAL, measResultNeighCells-r16 SEQUENCE { measResultNeighCellListNR MeasResultList2NR-r16 OPTIONAL, measResultNeighCellListEUTRA MeasResultList2EUTRA-r16 OPTIONAL }, numberOfConnFail-r16 INTEGER (1..8), perRAInfoList-r16 PerRAInfoList-r16, timeSinceFailure-r16 TimeSinceFailure-r16, ... } ConnEstFailReportList-r17 ::= SEQUENCE (SIZE (1..maxCEFReport-r17)) OF ConnEstFailReport-r16 MeasResultServingCell-r16 ::= SEQUENCE { resultsSSB-Cell MeasQuantityResults, resultsSSB SEQUENCE{ best-ssb-Index SSB-Index, best-ssb-Results MeasQuantityResults, numberOfGoodSSB INTEGER (1..maxNrofSSBs-r16) } OPTIONAL } MeasResultFailedCell-r16 ::= SEQUENCE { cgi-Info CGI-Info-Logging-r16, measResult-r16 SEQUENCE { cellResults-r16 SEQUENCE{ resultsSSB-Cell-r16 MeasQuantityResults }, rsIndexResults-r16 SEQUENCE{ resultsSSB-Indexes-r16 ResultsPerSSB-IndexList } } } RA-ReportList-r16 ::= SEQUENCE (SIZE (1..maxRAReport-r16)) OF RA-Report-r16 RA-Report-r16 ::= SEQUENCE { cellId-r16 CHOICE { cellGlobalId-r16 CGI-Info-Logging-r16, pci-arfcn-r16 PCI-ARFCN-NR-r16 }, ra-InformationCommon-r16 RA-InformationCommon-r16 OPTIONAL, raPurpose-r16 ENUMERATED {accessRelated, beamFailureRecovery, reconfigurationWithSync, ulUnSynchronized, schedulingRequestFailure, noPUCCHResourceAvailable, requestForOtherSI, msg3RequestForOtherSI- r17, spare8ltmCellSwitch-r19, ltmRachLessFallback-r19spare7, spare6, spare5, spare4, spare3, spare2, spare1}, ..., [[ spCellID-r17 CGI-Info-Logging-r16 OPTIONAL ]] } RA-InformationCommon-r16 ::= SEQUENCE { absoluteFrequencyPointA-r16 ARFCN-ValueNR, locationAndBandwidth-r16 INTEGER (0..37949), subcarrierSpacing-r16 SubcarrierSpacing, msg1-FrequencyStart-r16 INTEGER (0..maxNrofPhysicalResourceBlocks-1) OPTIONAL, msg1-FrequencyStartCFRA-r16 INTEGER (0..maxNrofPhysicalResourceBlocks-1) OPTIONAL, msg1-SubcarrierSpacing-r16 SubcarrierSpacing OPTIONAL, msg1-SubcarrierSpacingCFRA-r16 SubcarrierSpacing OPTIONAL, msg1-FDM-r16 ENUMERATED {one, two, four, eight} OPTIONAL, msg1-FDMCFRA-r16 ENUMERATED {one, two, four, eight} OPTIONAL, perRAInfoList-r16 PerRAInfoList-r16, ..., [[ perRAInfoList-v1660 PerRAInfoList-v1660 OPTIONAL ]], [[ msg1-SCS-From-prach-ConfigurationIndex-r16 ENUMERATED {kHz1dot25, kHz5, spare2, spare1} OPTIONAL ]], [[ msg1-SCS-From-prach-ConfigurationIndexCFRA-r16 ENUMERATED {kHz1dot25, kHz5, spare2, spare1} OPTIONAL ]], [[ msgA-RO-FrequencyStart-r17 INTEGER (0..maxNrofPhysicalResourceBlocks-1) OPTIONAL, msgA-RO-FrequencyStartCFRA-r17 INTEGER (0..maxNrofPhysicalResourceBlocks-1) OPTIONAL, msgA-SubcarrierSpacing-r17 SubcarrierSpacing OPTIONAL, msgA-RO-FDM-r17 ENUMERATED {one, two, four, eight} OPTIONAL, msgA-RO-FDMCFRA-r17 ENUMERATED {one, two, four, eight} OPTIONAL, msgA-SCS-From-prach-ConfigurationIndex-r17 ENUMERATED {kHz1dot25, kHz5, spare2, spare1} OPTIONAL, msgA-TransMax-r17 ENUMERATED {n1, n2, n4, n6, n8, n10, n20, n50, n100, n200} OPTIONAL, msgA-MCS-r17 INTEGER (0..15) OPTIONAL, nrofPRBs-PerMsgA-PO-r17 INTEGER (1..32) OPTIONAL, msgA-PUSCH-TimeDomainAllocation-r17 INTEGER (1..maxNrofUL-Allocations) OPTIONAL, frequencyStartMsgA-PUSCH-r17 INTEGER (0..maxNrofPhysicalResourceBlocks-1) OPTIONAL, nrofMsgA-PO-FDM-r17 ENUMERATED {one, two, four, eight} OPTIONAL, dlPathlossRSRP-r17 RSRP-Range OPTIONAL, intendedSIBs-r17 SEQUENCE (SIZE (1..maxSIB)) OF SIB-Type-r17 OPTIONAL, ssbsForSI-Acquisition-r17 SEQUENCE (SIZE (1..maxNrofSSBs- r16)) OF SSB-Index OPTIONAL, msgA-PUSCH-PayloadSize-r17 BIT STRING (SIZE (5)) OPTIONAL, onDemandSISuccess-r17 ENUMERATED {true} OPTIONAL, ]] } PerRAInfoList-r16 ::= SEQUENCE (SIZE (1..200)) OF PerRAInfo-r16 PerRAInfoList-v1660 ::= SEQUENCE (SIZE (1..200)) OF PerRACSI-RSInfo-v1660 PerRAInfo-r16 ::= CHOICE { perRASSBInfoList-r16 PerRASSBInfo-r16, perRACSI-RSInfoList-r16 PerRACSI-RSInfo-r16 } PerRASSBInfo-r16 ::= SEQUENCE { ssb-Index-r16 SSB-Index, numberOfPreamblesSentOnSSB-r16 INTEGER (1..200), perRAAttemptInfoList-r16 PerRAAttemptInfoList-r16 } PerRACSI-RSInfo-r16 ::= SEQUENCE { csi-RS-Index-r16 CSI-RS-Index, numberOfPreamblesSentOnCSI-RS-r16 INTEGER (1..200) } PerRACSI-RSInfo-v1660 ::= SEQUENCE { csi-RS-Index-v1660 INTEGER (1..96) OPTIONAL } PerRAAttemptInfoList-r16 ::= SEQUENCE (SIZE (1..200)) OF PerRAAttemptInfo-r16 PerRAAttemptInfo-r16 ::= SEQUENCE { contentionDetected-r16 BOOLEAN OPTIONAL, dlRSRPAboveThreshold-r16 BOOLEAN OPTIONAL, ..., [[ fallbackToFourStepRA-r17 ENUMERATED {true} OPTIONAL ]] } SIB-Type-r17 ::= ENUMERATED {sibType2, sibType3, sibType4, sibType5, sibType9, sibType10-v1610, sibType11-v1610, sibType12-v1610,

[0004] RA-Report field descriptions cellID This field indicates the CGI of the cell in which the associated random access procedure was performed. contentionDetected This field is used to indicate that contention was detected for the transmitted preamble in the given random access attempt or not. This field is not included when the UE performs random access attempt is using contention free random-access resources or when the raPurpose is set to requestForOtherSI or when the RA attempt is a 2-step RA attempt and fallback to 4-step RA did not occur (i.e. fallbackToFourStepRA is not included). csi-RS-Index, csi-RS-Index-v1660 This field is used to indicate the CSI-RS index corresponding to the random access attempt. If the random access procedure is for beam failure recovery, the field indicates the NZP- CSI-RS-ResourceId. For CSI-RS index larger than maxNrofCSI-RS-ResourcesRRM-1, the index value is the sum of csi-RS-Index (without suffix) and csi-RS-Index-v1660. dlPathlossRSRP Measeured RSRP of the DL pathloss reference obtained at the time of RA_Type selection stage of the RA procedure as captured in TS 38.321 [3]. dlRSRPAboveThreshold In 4 step random access procedure, this field is used to indicate whether the DL beam (SSB) quality associated to the random access attempt was above or below the threshold rsrp-ThresholdSSB in beamFailureRecoveryConfig in UL BWP configuration of UL BWP selected for random access procedure initiated for beam failure recovery; Otherwise, rsrp- ThresholdSSB in rach-ConfigCommon in UL BWP configuration of UL BWP selected for random access procedure. In 2 step random access procedure, this field is used to indicate whether the DL beam (SSB) quality associated to the random access attempt was above or below the threshold msgA-RSRP-ThresholdSSB in rach-ConfigCommonTwoStepRA in UL BWP configuration of UL BWP selected for random access procedure. fallbackToFourStepRA This field indicates if a fallback indication in MsgB is received (according to TS 38.321 [3]) for the 2-step random access attempt. intendedSIBs This field indicates the SIB(s) the UE wanted to receive as a result of the on demand SI request (when the RA procedure is a used as a SI request) initiated by the UE. That is, it indicates the one(s) of the SIB(s) in the SI message(s) requested to be broadcast that the UE was interested in. msg1-SCS-From-prach-ConfigurationIndex This field is set by the UE with the corresponding SCS for CBRA as derived from the prach-ConfigurationIndex in RACH-ConfigGeneric when the msg1-SubcarrierSpacing is absent; otherwise, this field is absent. msg1-SCS-From-prach-ConfigurationIndexCFRA This field is set by the UE with the corresponding SCS for CFRA as derived from the prach-ConfigurationIndex in RACH-ConfigGeneric when the msg1-SubcarrierSpacing is absent; otherwise, this field is absent. msgA-PUSCH-PayloadSize This field indicates the size of the overall payload available in the UE buffer at the time of initiating the 2 step RA procedure. The value refers to the index of TS 38.321, table 6.1.3.1-1, corresponding to the UE buffer size. msgA-RO-FDM This field indicates the number of msgA PRACH transmission occasions Frequency- Division Multiplexed in one time instance for the PRACH resources configured for 2-step CBRA.. msgA-RO-FDMCFRA This field indicates the number of msgA PRACH transmission occasions Frequency- Division Multiplexed in one time instance for the PRACH resources configured for 2-step CFRA. msgA-RO-FrequencyStart This field indicates the lowest resource block of the contention based random-access resources for 2-step CBRA in the random-access procedure. The indication has the form of the offset of the lowest PRACH transmissions occasion with respect to PRB 0 in the frequency domain. msgA-RO-FrequencyStartCFRA This field indicates the lowest resource block of the contention free random-access resources for the 2-step CFRA in the random-access procedure. The indication has the form of the offset of the lowest PRACH transmissions occasion with respect to PRB 0 in the frequency domain. msgA-SCS-From-prach-ConfigurationIndex This field is set by the UE with the corresponding SCS as derived from the msgA-PRACH- ConfigurationIndex in RACH-ConfigGenericTwoStepRA (see tables Table 6.3.3.1-1, Table 6.3.3.1-2, Table 6.3.3.2-2 and Table 6.3.3.2-3, TS 38.211

[0016] ) when the msgA- SubcarrierSpacing is absent and when only 2-step random-access resources are available in the UL BWP used in the random-access procedure; otherwise, this field is absent. numberOfPreamblesSentOnCSI-RS This field is used to indicate the total number of successive RA preambles that were transmitted on the corresponding CSI-RS. numberOfPreamblesSentOnSSB This field is used to indicate the total number of successive RA preambles that were transmitted on the corresponding SS / PBCH block. onDemandSISuccess This field is set to true when the RA report entry is included because of either msg1 based on demand SI request or msg3 based on demand SI request and if the on-demand SI request is successful. Otherwise, the field is absent. perRAAttemptInfoList This field provides detailed information about a random access attempt. perRACSI-RSInfoList This field provides detailed information about the successive random access attempts associated to the same CSI-RS. perRASSBInfoList This field provides detailed information about the successive random access attempts associated to the same SS / PBCH block. ra-InformationCommon This field is used to provide information on random access attempts. This field is mandatory present.

[0005] raPurpose This field is used to indicate the RA scenario for which the RA report entry is triggered. The RA accesses associated to Initial access from RRC_IDLE, RRC re-establishment procedure, transition from RRC-INACTIVE. The indicator beamFailureRecovery is used in case of successful beam failure recovery related RA procedure in the SpCell. The indicator reconfigurationWithSync is used if the UE executes a reconfiguration with sync. The indicator ulUnSynchronized is used if the random access procedure is initiated in a SpCell by DL or UL data arrival during RRC_CONNECTED when the timeAlignmentTimer is not running in the PTAG or if the RA procedure is initiated in a serving cell by a PDCCH order. The indicator schedulingRequestFailure is used in case of SR failures. The indicator noPUCCHResourceAvailable is used when the UE has no valid SR PUCCH resources configured. The indicator requestForOtherSI is used for MSG1 based on demand SI request. The indicator msg3RequestForOtherSI is used in case of MSG3 based SI request. The field can also be used for the SCG-related RA-Report when the raPurpose is set to beamFailureRecovery, reconfigurationWithSync, ulUnSynchronized, schedulingRequestFailure and noPUCCHResourceAvailable. The indicator ltmCellSwitch is used in case of initiating RA procedure for LTM cell switch in an SpCell. The indicator of ltmRachLessFallback-r19 is used in case of initiating RA procedure for the failure of RACH-less LTM cell switch command. spCellID This field is used to indicate the CGI of the SpCell of the cell group associated to the SCell in which the associated random access procedure was performed. If the UE performs RA procedure on a SCell associated to the MCG, then this field is set to the CGI of the PCell and if the UE performs RA procedure on a SCell associated to the SCG, then this field is set to the CGI of the PSCell. If the CGI of the PSCell is not available at the UE for the RA procedure performed on a SCell associated to the SCG or for the RA procedure on the PSCell, this field is set to the CGI of the PCell. Otherwise, the field is absent. ssb-Index This field is used to indicate the SS / PBCH index of the SS / PBCH block corresponding to the random access attempt. ssbsForSI-Acquisition This field indicates the SSB(s) (in the form of SSB index(es)) that the UE used to receive the requested SI message(s). The field is present if the purpose of the random access procedure was to request on-demand SI (i.e. if the raPurpose is set to requestForOtherSI or msg3RequestForOtherSI). Otherwise, the field is absent. Upon successfully performing random-access procedure initialized with 4-step or 2-step RA type, or upon failed or successfully completed on-demand system information acquisition procedure in RRC_IDLE or RRC_INACTIVE state, or upon failed or successfully completed RA-SDT operation as specified in clause 5.3.13.5, the UE shall: 1> if the RPLMN or the PLMN selected by upper layers (see TS24.501

[0023] ) from the PLMN(s) included in the plmn-IdentityList in SIB1 is not included in plmn-IdentityList stored in a non-empty VarRA-Report; or 1> if the registered SNPN identity or the SNPN identity selected by upper layers (see TS24.501

[0023] ) from the list of SNPN(s) included in the NPN-IdentityInfoList in SIB1is not included in snpn-IdentityList stored in a non-empty VarRA-Report: 2> clear the information included in VarRA-Report; 1> if the UE is not in SNPN access mode and if the number of RA-Report entries stored in the ra-ReportList in VarRA-Report is less than maxRAReport: 2> if the number of PLMN entries in plmn-IdentityList in identityList stored in VarRA-Report is less than maxPLMN; or 2> if the number of PLMN entries in plmn-IdentityList in identityList stored in VarRA-Report is equal to maxPLMN and the list of EPLMNs is subset of or equal to the plmn-IdentityList stored in VarRA- Report: 3> append the following contents associated to the random-access procedure as a new entry in the VarRA-Report: 4> if the list of EPLMNs has been stored by the UE: 5> set the plmn-IdentityList to include the list of EPLMNs stored by the UE (i.e. includes the RPLMN) without exceeding the limit of maxPLMN; 4> else: 5> set the plmn-Identity, in plmn-IdentityList, to the PLMN selected by upper layers (see TS 24.501

[0023] ) from the PLMN(s) included in the plmn-IdentityInfoList in SIB1; 4> set the cellId to the global cell identity and the tracking area code, if available, otherwise to the physical cell identity and carrier frequency of the cell in which the corresponding random- access preamble was transmitted; 4> if the UE supports spCell ID indication: 5> if the corresponding random-access procedure was performed on an SCell of MCG: 6> set the spCellId to the global cell identity of the PCell; 5> if the corresponding random-access procedure was performed on an SCell of SCG: 6> set the spCellId to the global cell identity of the PSCell, if available, otherwise, set the spCellId to the global cell identity of the PCell; 5> if the corresponding random-access procedure was performed on PSCell: 6> if the cellId is not set to the global cell identity of the PSCell, set the spCellId to the global cell identity of the PCell; 4> set the raPurpose to include the purpose of triggering the random-access procedure; 4> set the ra-InformationCommon as specified in clause 5.7.10.5. > if the UE is in SNPN access mode and if the number of RA-Report entries stored in the ra-ReportList in VarRA-Report is less than maxRAReport: 2> if the number of SNPN identity entries in snpn-IdentityList in identityList stored in VarRA-Report is less than maxNPN; or 2> if the number of SNPN identity entries in snpn-IdentityList in identityList stored in VarRA-Report is equal to maxNPN and the list of equivalent SNPN(s) is subset of or equal to the snpn-IdentityList stored in VarRA-Report: 3> append the following contents associated to the random-access procedure as a new entry in the VarRA-Report: 4> if the list of equivalent SNPN(s) has been stored by the UE: 5> set the snpn-IdentityList to include the list of equivalent SNPN(s) stored by the UE (i.e. includes the registered SNPN identity) without exceeding the limit of maxNPN; 4> else: 5> set the snpn-Identity, in snpn-IdentityList, to the SNPN identity selected by upper layers (see TS 24.501

[0023] ) from the SNPN identities included in the NPN-IdentityInfoList in SIB1; 4> set the cellId to the global cell identity and the tracking area code, if available, otherwise to the physical cell identity and carrier frequency of the cell in which the corresponding random- access preamble was transmitted; 4> if the UE supports spCell ID indication: 5> if the corresponding random-access procedure was performed on an SCell of MCG: 6> set the spCellId to the global cell identity of the PCell; 5> if the corresponding random-access procedure was performed on an SCell of SCG: 6> set the spCellId to the global cell identity of the PSCell, if available, otherwise, set the spCellId to the global cell identity of the PCell; 5> if the corresponding random-access procedure was performed on PSCell: 6> if the cellId is not set to the global cell identity of the PSCell, set the spCellId to the global cell identity of the PCell; 4> set the raPurpose to include the purpose of triggering the random-access procedure; 4> set the ra-InformationCommon as specified in clause 5.7.10.5. The UE may discard the random access report information, i.e. release the UE variable VarRA-Report, 48 hours after the last successful random access procedure or the failed or successfully completed on-demand system information acquisition procedure or the failed or successfully completed RA-SDT procedure related information is added to the VarRA- Report. Figure 5 shows an example of a communication system 500 in accordance with some embodiments. In the example, the communication system 500 includes a telecommunication network 502 that includes an access network 504, such as a radio access network (RAN), and a core network 506, which includes one or more core network nodes 508. The access network 504 includes one or more access network nodes, such as network nodes 510a and 510b (one or more of which may be generally referred to as network nodes 510), or any other similar 3rd Generation Partnership Project (3GPP) access nodes or non-3GPP access points. Moreover, as will be appreciated by those of skill in the art, a network node is not necessarily limited to an implementation in which a radio portion and a baseband portion are supplied and integrated by a single vendor. Thus, it will be understood that network nodes include disaggregated implementations or portions thereof. For example, in some embodiments, the telecommunication network 502 includes one or more Open-RAN (ORAN) network nodes. An ORAN network node is a node in the telecommunication network 502 that supports an ORAN specification (e.g., a specification published by the O-RAN Alliance, or any similar organization) and may operate alone or together with other nodes to implement one or more functionalities of any node in the telecommunication network 502, including one or more network nodes 510 and / or core network nodes 508. Examples of an ORAN network node include an open radio unit (O-RU), an open distributed unit (O- DU), an open central unit (O-CU), including an O-CU control plane (O-CU-CP) or an O-CU user plane (O-CU-UP), a RAN intelligent controller (near-real time or non-real time) hosting software or software plug-ins, such as a near-real time control application (e.g., xApp) or a non-real time control application (e.g., rApp), or any combination thereof (the adjective “open” designating support of an ORAN specification). The network node may support a specification by, for example, supporting an interface defined by the ORAN specification, such as an A1, F1, W1, E1, E2, X2, Xn interface, an open fronthaul user plane interface, or an open fronthaul management plane interface. Moreover, an ORAN access node may be a logical node in a physical node. Furthermore, an ORAN network node may be implemented in a virtualization environment (described further below) in which one or more network functions are virtualized. For example, the virtualization environment may include an O-Cloud computing platform orchestrated by a Service Management and Orchestration Framework via an O-2 interface defined by the O-RAN Alliance or comparable technologies. The network nodes 510 facilitate direct or indirect connection of user equipment (UE), such as by connecting UEs 512a, 512b, 512c, and 512d (one or more of which may be generally referred to as UEs 512) to the core network 506 over one or more wireless connections. Example wireless communications over a wireless connection include transmitting and / or receiving wireless signals using electromagnetic waves, radio waves, infrared waves, and / or other types of signals suitable for conveying information without the use of wires, cables, or other material conductors. Moreover, in different embodiments, the communication system 500 may include any number of wired or wireless networks, network nodes, UEs, and / or any other components or systems that may facilitate or participate in the communication of data and / or signals whether via wired or wireless connections. The communication system 500 may include and / or interface with any type of communication, telecommunication, data, cellular, radio network, and / or other similar type of system. The UEs 512 may be any of a wide variety of communication devices, including wireless devices arranged, configured, and / or operable to communicate wirelessly with the network nodes 510 and other communication devices. Similarly, the network nodes 510 are arranged, capable, configured, and / or operable to communicate directly or indirectly with the UEs 512 and / or with other network nodes or equipment in the telecommunication network 502 to enable and / or provide network access, such as wireless network access, and / or to perform other functions, such as administration in the telecommunication network 502. In the depicted example, the core network 506 connects the network nodes 510 to one or more hosts, such as host 516. These connections may be direct or indirect via one or more intermediary networks or devices. In other examples, network nodes may be directly coupled to hosts. The core network 506 includes one more core network nodes (e.g., core network node 508) that are structured with hardware and software components. Features of these components may be substantially similar to those described with respect to the UEs, network nodes, and / or hosts, such that the descriptions thereof are generally applicable to the corresponding components of the core network node 508. Example core network nodes include functions of one or more of a Mobile Switching Center (MSC), Mobility Management Entity (MME), Home Subscriber Server (HSS), Access and Mobility Management Function (AMF), Session Management Function (SMF), Authentication Server Function (AUSF), Subscription Identifier De- concealing function (SIDF), Unified Data Management (UDM), Security Edge Protection Proxy (SEPP), Network Exposure Function (NEF), and / or a User Plane Function (UPF). The host 516 may be under the ownership or control of a service provider other than an operator or provider of the access network 504 and / or the telecommunication network 502, and may be operated by the service provider or on behalf of the service provider. The host 516 may host a variety of applications to provide one or more services. Examples of such applications include the provision of live and / or pre-recorded audio / video content, data collection services, for example, retrieving and compiling data on various ambient conditions detected by a plurality of UEs, analytics functionality, social media, functions for controlling or otherwise interacting with remote devices, functions for an alarm and surveillance center, or any other such function performed by a server. As a whole, the communication system 500 of Figure 5 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system may be configured to operate according to predefined rules or procedures, such as specific standards that include, but are not limited to: Global System for Mobile Communications (GSM); Universal Mobile Telecommunications System (UMTS); Long Term Evolution (LTE), and / or other suitable 2G, 3G, 4G, 5G standards, or any applicable future generation standard (e.g., 6G); wireless local area network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards (WiFi); and / or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave, Near Field Communication (NFC) ZigBee, LiFi, and / or any low-power wide-area network (LPWAN) standards such as LoRa and Sigfox. In some examples, the telecommunication network 502 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunications network 502 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 502. For example, the telecommunications network 502 may provide Ultra Reliable Low Latency Communication (URLLC) services to some UEs, while providing Enhanced Mobile Broadband (eMBB) services to other UEs, and / or Massive Machine Type Communication (mMTC) / Massive IoT services to yet further UEs. In some examples, the UEs 512 are configured to transmit and / or receive information without direct human interaction. For instance, a UE may be designed to transmit information to the access network 504 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 504. Additionally, a UE may be configured for operating in single- or multi-RAT or multi-standard mode. For example, a UE may operate with any one or combination of Wi-Fi, NR (New Radio) and LTE, i.e. being configured for multi-radio dual connectivity (MR-DC), such as E-UTRAN (Evolved-UMTS Terrestrial Radio Access Network) New Radio – Dual Connectivity (EN-DC). In the example illustrated in Figure 5, the hub 514 communicates with the access network 504 to facilitate indirect communication between one or more UEs (e.g., UE 512c and / or 512d) and network nodes (e.g., network node 510b). In some examples, the hub 514 may be a controller, router, a content source and analytics node, or any of the other communication devices described herein regarding UEs. For example, the hub 514 may be a broadband router enabling access to the core network 506 for the UEs. As another example, the hub 514 may be a controller that sends commands or instructions to one or more actuators in the UEs. Commands or instructions may be received from the UEs, network nodes 510, or by executable code, script, process, or other instructions in the hub 514. As another example, the hub 514 may be a data collector that acts as temporary storage for UE data and, in some embodiments, may perform analysis or other processing of the data. As another example, the hub 514 may be a content source. For example, for a UE that is a VR headset, display, loudspeaker or other media delivery device, the hub 514 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 514 then provides to the UE either directly, after performing local processing, and / or after adding additional local content. In still another example, the hub 514 acts as a proxy server or orchestrator for the UEs, in particular if one or more of the UEs are low energy IoT devices. The hub 514 may have a constant / persistent or intermittent connection to the network node 510b. The hub 514 may also allow for a different communication scheme and / or schedule between the hub 514 and UEs (e.g., UE 512c and / or 512d), and between the hub 514 and the core network 506. In other examples, the hub 514 is connected to the core network 506 and / or one or more UEs via a wired connection. Moreover, the hub 514 may be configured to connect to an M2M service provider over the access network 504 and / or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 510 while still connected via the hub 514 via a wired or wireless connection. In some embodiments, the hub 514 may be a dedicated hub – that is, a hub whose primary function is to route communications to / from the UEs from / to the network node 510b. In other embodiments, the hub 514 may be a non-dedicated hub – that is, a device which is capable of operating to route communications between the UEs and network node 510b, but which is additionally capable of operating as a communication start and / or end point for certain data channels. Figure 6 shows a UE 600 in accordance with some embodiments. As used herein, a UE refers to a device capable, configured, arranged and / or operable to communicate wirelessly with network nodes and / or other UEs. Examples of a UE include, but are not limited to, a smart phone, mobile phone, cell phone, voice over IP (VoIP) phone, wireless local loop phone, desktop computer, personal digital assistant (PDA), wireless camera, gaming console or device, music storage device, playback appliance, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), smart device, wireless customer-premise equipment (CPE), vehicle, vehicle-mounted or vehicle embedded / integrated wireless device, etc. Other examples include any UE identified by the 3rd Generation Partnership Project (3GPP), including a narrow band internet of things (NB-IoT) UE, a machine type communication (MTC) UE, and / or an enhanced MTC (eMTC) UE. A UE may support device-to-device (D2D) communication, for example by implementing a 3GPP standard for sidelink communication, Dedicated Short-Range Communication (DSRC), vehicle-to- vehicle (V2V), vehicle-to-infrastructure (V2I), or vehicle-to-everything (V2X). In other examples, a UE may not necessarily have a user in the sense of a human user who owns and / or operates the relevant device. Instead, a UE may represent a device that is intended for sale to, or operation by, a human user but which may not, or which may not initially, be associated with a specific human user (e.g., a smart sprinkler controller). Alternatively, a UE may represent a device that is not intended for sale to, or operation by, an end user but which may be associated with or operated for the benefit of a user (e.g., a smart power meter). The UE 600 includes processing circuitry 602 that is operatively coupled via a bus 604 to an input / output interface 606, a power source 608, a memory 610, a communication interface 612, and / or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in Figure 6. The level of integration between the components may vary from one UE to another UE. Further, certain UEs may contain multiple instances of a component, such as multiple processors, memories, transceivers, transmitters, receivers, etc. The processing circuitry 602 is configured to process instructions and data and may be configured to implement any sequential state machine operative to execute instructions stored as machine-readable computer programs in the memory 610. The processing circuitry 602 may be implemented as one or more hardware-implemented state machines (e.g., in discrete logic, field-programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), etc.); programmable logic together with appropriate firmware; one or more stored computer programs, general-purpose processors, such as a microprocessor or digital signal processor (DSP), together with appropriate software; or any combination of the above. For example, the processing circuitry 602 may include multiple central processing units (CPUs). The processing circuitry 602 may be operable to provide, either alone or in conjunction with other UE 600 components, such as the memory 610, UE 600 functionality. For example, the processing circuitry 602 may be configured to cause the UE 602 to perform the methods as described with reference to Figure 2. In the example, the input / output interface 606 may be configured to provide an interface or interfaces to an input device, output device, or one or more input and / or output devices. Examples of an output device include a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof. An input device may allow a user to capture information into the UE 600. Examples of an input device include a touch-sensitive or presence-sensitive display, a camera (e.g., a digital camera, a digital video camera, a web camera, etc.), a microphone, a sensor, a mouse, a trackball, a directional pad, a trackpad, a scroll wheel, a smartcard, and the like. The presence-sensitive display may include a capacitive or resistive touch sensor to sense input from a user. A sensor may be, for instance, an accelerometer, a gyroscope, a tilt sensor, a force sensor, a magnetometer, an optical sensor, a proximity sensor, a biometric sensor, etc., or any combination thereof. An output device may use the same type of interface port as an input device. For example, a Universal Serial Bus (USB) port may be used to provide an input device and an output device. In some embodiments, the power source 608 is structured as a battery or battery pack. Other types of power sources, such as an external power source (e.g., an electricity outlet), photovoltaic device, or power cell, may be used. The power source 608 may further include power circuitry for delivering power from the power source 608 itself, and / or an external power source, to the various parts of the UE 600 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source 608. Power circuitry may perform any formatting, converting, or other modification to the power from the power source 608 to make the power suitable for the respective components of the UE 600 to which power is supplied. The memory 610 may be or be configured to include memory such as random access memory (RAM), read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read- only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory 610 includes one or more application programs 614, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 616. The memory 610 may store, for use by the UE 600, any of a variety of various operating systems or combinations of operating systems. The memory 610 may be configured to include a number of physical drive units, such as redundant array of independent disks (RAID), flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, high-density digital versatile disc (HD-DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, holographic digital data storage (HDDS) optical disc drive, external mini-dual in-line memory module (DIMM), synchronous dynamic random access memory (SDRAM), external micro-DIMM SDRAM, smartcard memory such as tamper resistant module in the form of a universal integrated circuit card (UICC) including one or more subscriber identity modules (SIMs), such as a USIM and / or ISIM, other memory, or any combination thereof. The UICC may for example be an embedded UICC (eUICC), integrated UICC (iUICC) or a removable UICC commonly known as ‘SIM card.’ The memory 610 may allow the UE 600 to access instructions, application programs and the like, stored on transitory or non-transitory memory media, to off-load data, or to upload data. An article of manufacture, such as one utilizing a communication system may be tangibly embodied as or in the memory 610, which may be or comprise a device-readable storage medium. The processing circuitry 602 may be configured to communicate with an access network or other network using the communication interface 612. The communication interface 612 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 622. The communication interface 612 may include one or more transceivers used to communicate, such as by communicating with one or more remote transceivers of another device capable of wireless communication (e.g., another UE or a network node in an access network). Each transceiver may include a transmitter 618 and / or a receiver 620 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter 618 and receiver 620 may be coupled to one or more antennas (e.g., antenna 622) and may share circuit components, software or firmware, or alternatively be implemented separately. In some embodiments, communication functions of the communication interface 612 may include cellular communication, Wi-Fi communication, LPWAN communication, data communication, voice communication, multimedia communication, short-range communications such as Bluetooth, near-field communication, location-based communication such as the use of the global positioning system (GPS) to determine a location, another like communication function, or any combination thereof. Communications may be implemented in according to one or more communication protocols and / or standards, such as IEEE 802.11, Code Division Multiplexing Access (CDMA), Wideband Code Division Multiple Access (WCDMA), GSM, LTE, New Radio (NR), UMTS, WiMax, Ethernet, transmission control protocol / internet protocol (TCP / IP), synchronous optical networking (SONET), Asynchronous Transfer Mode (ATM), QUIC, Hypertext Transfer Protocol (HTTP), and so forth. Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface 612, via a wireless connection to a network node. Data captured by sensors of a UE can be communicated through a wireless connection to a network node via another UE. The output may be periodic (e.g., once every 15 minutes if it reports the sensed temperature), random (e.g., to even out the load from reporting from several sensors), in response to a triggering event (e.g., when moisture is detected an alert is sent), in response to a request (e.g., a user initiated request), or a continuous stream (e.g., a live video feed of a patient). As another example, a UE comprises an actuator, a motor, or a switch, related to a communication interface configured to receive wireless input from a network node via a wireless connection. In response to the received wireless input the states of the actuator, the motor, or the switch may change. For example, the UE may comprise a motor that adjusts the control surfaces or rotors of a drone in flight according to the received input or controls a robotic arm performing a medical procedure according to the received input. A UE, when in the form of an Internet of Things (IoT) device, may be a device for use in one or more application domains, these domains comprising, but not limited to, city wearable technology, extended industrial application and healthcare. Non-limiting examples of such an IoT device are devices which are or which are embedded in: a connected refrigerator or freezer, a TV, a connected lighting device, an electricity meter, a robot vacuum cleaner, a voice controlled smart speaker, a home security camera, a motion detector, a thermostat, a smoke detector, a door / window sensor, a flood / moisture sensor, an electrical door lock, a connected doorbell, an air conditioning system like a heat pump, an autonomous vehicle, a surveillance system, a weather monitoring device, a vehicle parking monitoring device, an electric vehicle charging station, a smart watch, a fitness tracker, a head-mounted display for Augmented Reality (AR) or Virtual Reality (VR), a wearable for tactile augmentation or sensory enhancement, a water sprinkler, an animal- or item-tracking device, a sensor for monitoring a plant or animal, an industrial robot, an Unmanned Aerial Vehicle (UAV), and any kind of medical device, like a heart rate monitor or a remote controlled surgical robot. A UE in the form of an IoT device comprises circuitry and / or software in dependence on the intended application of the IoT device in addition to other components as described in relation to the UE 600 shown in Figure 6. As yet another specific example, in an IoT scenario, a UE may represent a machine or other device that performs monitoring and / or measurements, and transmits the results of such monitoring and / or measurements to another UE and / or a network node. The UE may in this case be an M2M device, which may in a 3GPP context be referred to as an MTC device. As one particular example, the UE may implement the 3GPP NB-IoT standard. In other scenarios, a UE may represent a vehicle, such as a car, a bus, a truck, a ship and an airplane, or other equipment that is capable of monitoring and / or reporting on its operational status or other functions associated with its operation. In practice, any number of UEs may be used together with respect to a single use case. For example, a first UE might be or be integrated in a drone and provide the drone’s speed information (obtained through a speed sensor) to a second UE that is a remote controller operating the drone. When the user makes changes from the remote controller, the first UE may adjust the throttle on the drone (e.g. by controlling an actuator) to increase or decrease the drone’s speed. The first and / or the second UE can also include more than one of the functionalities described above. For example, a UE might comprise the sensor and the actuator, and handle communication of data for both the speed sensor and the actuators. Figure 7 shows a network node 700 in accordance with some embodiments. As used herein, network node refers to equipment capable, configured, arranged and / or operable to communicate directly or indirectly with a UE and / or with other network nodes or equipment, in a telecommunication network. Examples of network nodes include, but are not limited to, access points (APs) (e.g., radio access points), base stations (BSs) (e.g., radio base stations, Node Bs, evolved Node Bs (eNBs) and NR NodeBs (gNBs)), O-RAN nodes or components of an O-RAN node (e.g., O-RU, O-DU, O-CU). Base stations may be categorized based on the amount of coverage they provide (or, stated differently, their transmit power level) and so, depending on the provided amount of coverage, may be referred to as femto base stations, pico base stations, micro base stations, or macro base stations. A base station may be a relay node or a relay donor node controlling a relay. A network node may also include one or more (or all) parts of a distributed radio base station such as centralized digital units, distributed units (e.g., in an O-RAN access node) and / or remote radio units (RRUs), sometimes referred to as Remote Radio Heads (RRHs). Such remote radio units may or may not be integrated with an antenna as an antenna integrated radio. Parts of a distributed radio base station may also be referred to as nodes in a distributed antenna system (DAS). Other examples of network nodes include multiple transmission point (multi-TRP) 5G access nodes, multi-standard radio (MSR) equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, multi-cell / multicast coordination entities (MCEs), Operation and Maintenance (O&M) nodes, Operations Support System (OSS) nodes, Self-Organizing Network (SON) nodes, positioning nodes (e.g., Evolved Serving Mobile Location Centers (E-SMLCs)), and / or Minimization of Drive Tests (MDTs). The network node 700 includes processing circuitry 702, a memory 704, a communication interface 706, and a power source 708, and / or any other component, or any combination thereof. The network node 700 may be composed of multiple physically separate components (e.g., a NodeB component and a RNC component, or a BTS component and a BSC component, etc.), which may each have their own respective components. In certain scenarios in which the network node 700 comprises multiple separate components (e.g., BTS and BSC components), one or more of the separate components may be shared among several network nodes. For example, a single RNC may control multiple NodeBs. In such a scenario, each unique NodeB and RNC pair, may in some instances be considered a single separate network node. In some embodiments, the network node 700 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate memory 704 for different RATs) and some components may be reused (e.g., a same antenna 710 may be shared by different RATs). The network node 700 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 700, for example GSM, WCDMA, LTE, NR, WiFi, Zigbee, Z-wave, LoRaWAN, Radio Frequency Identification (RFID) or Bluetooth wireless technologies. These wireless technologies may be integrated into the same or different chip or set of chips and other components within network node 700. The processing circuitry 702 may comprise a combination of one or more of a microprocessor, controller, microcontroller, central processing unit, digital signal processor, application-specific integrated circuit, field programmable gate array, or any other suitable computing device, resource, or combination of hardware, software and / or encoded logic operable to provide, either alone or in conjunction with other network node 700 components, such as the memory 704, network node 700 functionality. For example, the processing circuitry 702 may be configured to cause the network node to perform the methods as described with reference to Figure 3. In some embodiments, the processing circuitry 702 includes a system on a chip (SOC). In some embodiments, the processing circuitry 702 includes one or more of radio frequency (RF) transceiver circuitry 712 and baseband processing circuitry 714. In some embodiments, the radio frequency (RF) transceiver circuitry 712 and the baseband processing circuitry 714 may be on separate chips (or sets of chips), boards, or units, such as radio units and digital units. In alternative embodiments, part or all of RF transceiver circuitry 712 and baseband processing circuitry 714 may be on the same chip or set of chips, boards, or units. The memory 704 may comprise any form of volatile or non-volatile computer-readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and / or any other volatile or non-volatile, non- transitory device-readable and / or computer-executable memory devices that store information, data, and / or instructions that may be used by the processing circuitry 702. The memory 704 may store any suitable instructions, data, or information, including a computer program, software, an application including one or more of logic, rules, code, tables, and / or other instructions capable of being executed by the processing circuitry 702 and utilized by the network node 700. The memory 704 may be used to store any calculations made by the processing circuitry 702 and / or any data received via the communication interface 706. In some embodiments, the processing circuitry 702 and memory 704 is integrated. The communication interface 706 is used in wired or wireless communication of signaling and / or data between a network node, access network, and / or UE. As illustrated, the communication interface 706 comprises port(s) / terminal(s) 716 to send and receive data, for example to and from a network over a wired connection. The communication interface 706 also includes radio front-end circuitry 718 that may be coupled to, or in certain embodiments a part of, the antenna 710. Radio front-end circuitry 718 comprises filters 720 and amplifiers 722. The radio front-end circuitry 718 may be connected to an antenna 710 and processing circuitry 702. The radio front-end circuitry may be configured to condition signals communicated between antenna 710 and processing circuitry 702. The radio front-end circuitry 718 may receive digital data that is to be sent out to other network nodes or UEs via a wireless connection. The radio front-end circuitry 718 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 720 and / or amplifiers 722. The radio signal may then be transmitted via the antenna 710. Similarly, when receiving data, the antenna 710 may collect radio signals which are then converted into digital data by the radio front-end circuitry 718. The digital data may be passed to the processing circuitry 702. In other embodiments, the communication interface may comprise different components and / or different combinations of components. In certain alternative embodiments, the network node 700 does not include separate radio front-end circuitry 718, instead, the processing circuitry 702 includes radio front-end circuitry and is connected to the antenna 710. Similarly, in some embodiments, all or some of the RF transceiver circuitry 712 is part of the communication interface 706. In still other embodiments, the communication interface 706 includes one or more ports or terminals 716, the radio front-end circuitry 718, and the RF transceiver circuitry 712, as part of a radio unit (not shown), and the communication interface 706 communicates with the baseband processing circuitry 714, which is part of a digital unit (not shown). The antenna 710 may include one or more antennas, or antenna arrays, configured to send and / or receive wireless signals. The antenna 710 may be coupled to the radio front-end circuitry 718 and may be any type of antenna capable of transmitting and receiving data and / or signals wirelessly. In certain embodiments, the antenna 710 is separate from the network node 700 and connectable to the network node 700 through an interface or port. The antenna 710, communication interface 706, and / or the processing circuitry 702 may be configured to perform any receiving operations and / or certain obtaining operations described herein as being performed by the network node. Any information, data and / or signals may be received from a UE, another network node and / or any other network equipment. Similarly, the antenna 710, the communication interface 706, and / or the processing circuitry 702 may be configured to perform any transmitting operations described herein as being performed by the network node. Any information, data and / or signals may be transmitted to a UE, another network node and / or any other network equipment. The power source 708 provides power to the various components of network node 700 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source 708 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 700 with power for performing the functionality described herein. For example, the network node 700 may be connectable to an external power source (e.g., the power grid, an electricity outlet) via an input circuitry or interface such as an electrical cable, whereby the external power source supplies power to power circuitry of the power source 708. As a further example, the power source 708 may comprise a source of power in the form of a battery or battery pack which is connected to, or integrated in, power circuitry. The battery may provide backup power should the external power source fail. Embodiments of the network node 700 may include additional components beyond those shown in Figure 7 for providing certain aspects of the network node’s functionality, including any of the functionality described herein and / or any functionality necessary to support the subject matter described herein. For example, the network node 700 may include user interface equipment to allow input of information into the network node 700 and to allow output of information from the network node 700. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 700. 5567 Figure 8 is a block diagram illustrating a virtualization environment 800 in which functions implemented by some embodiments may be virtualized. In the present context, virtualizing means creating virtual versions of apparatuses or devices which may include virtualizing hardware platforms, storage devices and networking resources. As used herein, virtualization can be applied to any device described herein, or components thereof, and relates to an implementation in which at least a portion of the functionality is implemented as one or more virtual components. Some or all of the functions described herein may be implemented as virtual components executed by one or more virtual machines (VMs) implemented in one or more virtual environments 800 hosted by one or more of hardware nodes, such as a hardware computing device that operates as a network node, UE, core network node, or host. Further, in embodiments in which the virtual node does not require radio connectivity (e.g., a core network node or host), then the node may be entirely virtualized. In some embodiments, the virtualization environment 800 includes components defined by the O-RAN Alliance, such as an O- Cloud environment orchestrated by a Service Management and Orchestration Framework via an O-2 interface. Applications 802 (which may alternatively be called software instances, virtual appliances, network functions, virtual nodes, virtual network functions, etc.) are run in the virtualization environment Q400 to implement some of the features, functions, and / or benefits of some of the embodiments disclosed herein. Hardware 804 includes processing circuitry, memory that stores software and / or instructions executable by hardware processing circuitry, and / or other hardware devices as described herein, such as a network interface, input / output interface, and so forth. Software may be executed by the processing circuitry to instantiate one or more virtualization layers 806 (also referred to as hypervisors or virtual machine monitors (VMMs)), provide VMs 808a and 808b (one or more of which may be generally referred to as VMs 808), and / or perform any of the functions, features and / or benefits described in relation with some embodiments described herein. The virtualization layer 806 may present a virtual operating platform that appears like networking hardware to the VMs 808. The VMs 808 comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and may be run by a corresponding virtualization layer 806. Different embodiments of the instance of a virtual appliance 802 may be implemented on one or more of VMs 808, and the implementations may be made in different ways. Virtualization of the hardware is in some contexts referred to as network function virtualization (NFV). NFV may be used to consolidate many network equipment types onto industry standard high volume server hardware, physical switches, and physical storage, which can be located in data centers, and customer premise equipment. In the context of NFV, a VM 808 may be a software implementation of a physical machine that runs programs as if they were executing on a physical, non-virtualized machine. Each of the VMs 808, and that part of hardware 804 that executes that VM, be it hardware dedicated to that VM and / or hardware shared by that VM with others of the VMs, forms separate virtual network elements. Still in the context of NFV, a virtual network function is responsible for handling specific network functions that run in one or more VMs 808 on top of the hardware 804 and corresponds to the application 802. Hardware 804 may be implemented in a standalone network node with generic or specific components. Hardware 804 may implement some functions via virtualization. Alternatively, hardware 804 may be part of a larger cluster of hardware (e.g. such as in a data center or CPE) where many hardware nodes work together and are managed via management and orchestration 810, which, among others, oversees lifecycle management of applications 802. In some embodiments, hardware 804 is coupled to one or more radio units that each include one or more transmitters and one or more receivers that may be coupled to one or more antennas. Radio units may communicate directly with other hardware nodes via one or more appropriate network interfaces and may be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a radio access node or a base station. In some embodiments, some signaling can be provided with the use of a control system 812 which may alternatively be used for communication between hardware nodes and radio units. Although the computing devices described herein (e.g., UEs, network nodes, hosts) may include the illustrated combination of hardware components, other embodiments may comprise computing devices with different combinations of components. It is to be understood that these computing devices may comprise any suitable combination of hardware and / or software needed to perform the tasks, features, functions and methods disclosed herein. Determining, calculating, obtaining or similar operations described herein may be performed by processing circuitry, which may process information by, for example, converting the obtained information into other information, comparing the obtained information or converted information to information stored in the network node, and / or performing one or more operations based on the obtained information or converted information, and as a result of said processing making a determination. Moreover, while components are depicted as single boxes located within a larger box, or nested within multiple boxes, in practice, computing devices may comprise multiple different physical components that make up a single illustrated component, and functionality may be partitioned between separate components. For example, a communication interface may be configured to include any of the components described herein, and / or the functionality of the components may be partitioned between the processing circuitry and the communication interface. In another example, non-computationally intensive functions of any of such components may be implemented in software or firmware and computationally intensive functions may be implemented in hardware. In certain embodiments, some or all of the functionality described herein may be provided by processing circuitry executing instructions stored on in memory, which in certain embodiments may be a computer program product in the form of a non-transitory computer-readable storage medium. In alternative embodiments, some or all of the functionality may be provided by the processing circuitry without executing instructions stored on a separate or discrete device-readable storage medium, such as in a hard-wired manner. In any of those particular embodiments, whether executing instructions stored on a non-transitory computer-readable storage medium or not, the processing circuitry can be configured to perform the described functionality. The benefits provided by such functionality are not limited to the processing circuitry alone or to other components of the computing device, but are enjoyed by the computing device as a whole, and / or by end users and a wireless network generally.

[0006] EMBODIMENTS Group A Embodiments 1.A method performed by a user equipment, UE, being served by a first cell of a first network node, the method comprising: performing a random access, RA, procedure for a lower-layer triggered mobility, LTM, cell switch to a second cell; and determining first information associated with the RA procedure for the LTM cell switch to the second cell. 2. The method of embodiment 1 further comprising storing or logging the first information. 3. The method of embodiment 1 or 2 further comprising transmitting, to a network node, at least some of the first information. 4. The method of embodiment 3, wherein the RA procedure is successful. 5. The method of embodiment 4, wherein the network node to which the at least some of the first information is transmitted is a second network node serving the second cell. 6. The method of embodiment 3, wherein the RA procedure is unsuccessful. 7. The method of embodiment 6, wherein the network node to which the at least some of the first information is transmitted is the first network node. 8. The method of any of embodiments 3-7, wherein the at least some of the first information is transmitted in a random access report. 9. The method of any of embodiments 3-7, wherein the at least some of the first information is transmitted in one or more of: a radio link failure, RLF, report; a successful handover report, SHR; a successful PSCell change report, SPR; an UEInformationResponse message; an SCGFailureInformation message; and an MCGFailureInformation message. 0. The method of any preceding embodiment, wherein the first information associated with the RA procedure comprises an indication that a purpose of the RA procedure is an LTM cell switch operation. 1. The method of any preceding embodiment, wherein the first information associated with the RA procedure comprises one or more of: an indication of what triggered the UE to perform the RA procedure; an indication that the RA procedure was performed responsive to a downlink control information, DCI, indication; and an indication of a power level applied by the UE during the RA procedure. 2. The method of any preceding embodiment, wherein the first information comprises information relating to one or more timing advance, TA, values associated with the RA procedure. 3. The method of embodiment 12, wherein the information relating to one or more TA values comprises one or more of: an indication of whether a random-access configuration received by the UE and to be used for acquiring a TA for the second cell allows reception of an RA response, RAR from the first cell; an indication of a minimum time interval between the UE receiving from the first cell a trigger for TA establishment and the UE performing the RA procedure for the LTM cell switch to the second cell; an indication of whether the UE stored a TA value received from the first cell for the second cell; an indication of whether there is any difference between a TA value that the UE received from the first cell for the second cell and a TA value that the UE received as part of an RA response message during the RA procedure; an indication of a difference between a TA value that the UE received from the first cell for the second cell and a TA that the UE received as part of an RA response message during the RA procedure; an indication of a TA value for the second cell that the UE received during the RA procedure; and an indication of TA values for one or more candidate cells for cell switch. 14. The method of any preceding embodiment, wherein the first information comprises an indication of at least one beam associated with the RA procedure. 15. The method of embodiment 14, wherein the indication of a beam comprises one or more of: an indication of a beam in the second cell towards which the UE performed the RA procedure; an indication of a beam in the second cell that was indicated to the UE as a beam toward which the UE should perform the RA procedure; and an indication of a beam in the second cell selected by the UE based on beam measurements obtained before or after performing the RA procedure. 16. The method of any preceding embodiment, wherein the first information comprises beam measurements associated with the RA procedure. 17. The method of embodiment 16, wherein the beam measurements comprise one or both of: beam measurements obtained when the UE is triggered to transmit a preamble for timing advance, TA, establishment for the LTM cell switch to the second cell; and beam measurements obtained when the UE receives an LTM cell switch command to perform the RA procedure for the LTM cell switch to the second cell. 18. The method of embodiment 16 or 17, wherein the beam measurements comprise one or more of: a signal strength value; a quality value; a cell identifier; a Reference Signal Received Power, RSRP; a Layer-1 RSRP; a Synchronization Signal RSRP; a Reference Signal Received Quality, RSRQ; a Signal to Interference plus Noise Ratio, SINR; a beam index; a beam identifier; and a Synchronization Signal Block, SSB, index. 19. The method of any preceding embodiment, wherein the method further comprises: performing the RA procedure responsive to receiving a first indication to perform the RA procedure for the LTM cell switch to the second cell. 20. The method of embodiment 19, wherein the first indication comprises or is comprised in an LTM cell switch command for the LTM cell switch to the second cell. 21. The method of embodiment 20, wherein the first information comprises information relating to the LTM cell switch command. 2. The method of embodiment 21, wherein the information relating to the LTM cell switch command comprises one or more of: an indication of whether the LTM cell switch command allows reception of an RA response, RAR; an indication of whether the LTM cell switch command allows preamble retransmission; an indication of whether the LTM cell switch command allows power ramping; and an indication of whether the LTM cell switch command comprises timing advance, TA, information. 3. The method of any of embodiments 19-22, wherein the first indication comprises or is comprised in one or more of: a medium access control, MAC, control element, CE; a Physical Downlink Control Channel, PDCCH, order; and a downlink control information, DCI, indication. 4. The method of any of embodiments 19-23, wherein the first indication comprises one or more of: an indication of an LTM candidate cell configuration for the second cell; an indication of a beam index toward which the UE should perform the RA procedure; an LTM candidate configuration identifier; and a Timing Advance value. 5. The method of any one of embodiment 19 to 24, wherein the first indication is received from the first network node serving the first cell. 6. The method of any preceding embodiment, wherein the first cell is one of: a primary cell, PCell, for the UE; a primary cell of a secondary cell group, PSCell, for the UE; and a secondary cell, SCell, for the UE. 7. The method of any preceding embodiment, wherein the second cell is one or more of: a primary cell, PCell, for the UE; a primary cell of a secondary cell group, PSCell, for the UE; a secondary cell, SCell, for the UE; a cell of the first network node; and a cell of a different network node to the first cell. 8. The method of any preceding embodiment, wherein the second cell is configured by the UE as an LTM candidate target cell. 29. The method of any preceding embodiment, wherein the method further comprises: performing the RA procedure responsive to determining that a Random Access Channel less, RACH-less, LTM cell switch to the second cell has failed. 30. The method of embodiment 29, wherein determining that a RACH-less LTM cell switch to the second cell has failed comprises determining that a supervision timer has expired without the UE receiving a Physical Downlink Control Channel, PDCCH, transmission. 31. The method of any preceding embodiment, wherein performing the RA procedure comprises one or more of: transmitting an RA preamble to a second network node serving the second cell; receiving a timing advance command, TAC, for the LTM cell switch to the second cell; receiving a trigger for re-transmission of the RA preamble to the second network node serving the second cell; retransmitting the RA preamble to the second network node; receiving an RA response, RAR, from the second network node; receiving a timing advance, TA, value from the first network node; detecting contention; and selecting an RAR. 32. The method of any of the previous embodiments, further comprising: providing user data; and forwarding the user data to a host via the transmission to the network node. Group B Embodiments 33. A method performed by a network node, wherein a user equipment, UE, is being served by a first cell of a first network node, the method comprising: receiving, from the UE, first information associated with a random access, RA, procedure for a lower-layer triggered mobility, LTM, cell switch to a second cell. 34. The method of embodiment 33, wherein the method further comprises: prior to receiving the first information, performing a random access, RA, procedure with the UE for the LTM cell switch of the UE to the second cell. 35. The method of embodiment 34, wherein performing the RA procedure comprises one or more of: receiving an RA preamble from the UE; transmitting a timing advance command, TAC, for the LTM cell switch to the second cell; transmitting a trigger for re-transmission of the RA preamble to the UE; receiving a retransmission of the RA preamble from the UE; and transmitting an RA response, RAR, to the UE. 36. The method of embodiment 34 or 35, wherein the RA procedure is successful. 37. The method of any of embodiments 33-36, wherein the network node is a second network node serving the second cell. 38. The method of embodiment 33, wherein the network node is the first network node. 39. The method of any of embodiments 33-38, wherein the first information is received in a random access report. 40. The method of any of embodiments 33-38, wherein the first information is received in one or more of: a radio link failure, RLF, report; a successful handover report, SHR; a successful PSCell change report, SPR; an UEInformationResponse message; an SCGFailureInformation message; and an MCGFailureInformation message. 41. The method of any embodiments 33-40, wherein the first information associated with the RA procedure comprises an indication that a purpose of the RA procedure is an LTM cell switch operation. 42. The method of any of embodiments 33-41, wherein the first information associated with the RA procedure comprises one or more of: an indication of what triggered the UE to perform the RA procedure; an indication that the RA procedure was performed responsive to a downlink control information, DCI, indication; and an indication of a power level applied by the UE during the RA procedure. 3. The method of any of embodiments 33-42, wherein the first information comprises information relating to one or more timing advance, TA, values associated with the RA procedure. 4. The method of embodiment 43, wherein the information relating to one or more TA values comprises one or more of: an indication of whether a random-access configuration received by the UE and to be used for acquiring a TA towards the second cell allows reception of an RA response, RAR, from the first cell; an indication of a minimum time interval between the UE receiving from the first cell a trigger for TA establishment, and the UE performing the RA procedure for the LTM cell switch to the second cell; an indication of whether the UE stored a TA value received from the first cell for the second cell; an indication of whether there is any difference between a TA value that the UE received from the first cell for the second cell and a TA value that the UE received as part of an RA response message during the RA procedure; an indication of a difference between a TA value that the UE received from the first cell for the second cell and a TA value that the UE received as part of an RA response message during the RA procedure; an indication of a TA value for the second cell that the UE received during the RA procedure; and an indication of TA values for one or more candidate cells for cell switch. 5. The method of any of embodiments 33-44, wherein the first information comprises an indication of at least one beam associated with the RA procedure. 6. The method of embodiment 45, wherein the indication of at least one beam comprises one or more of: an indication of a beam of the second cell towards which the UE performed the RA procedure; an indication of a beam of the second cell that was indicated to the UE as a beam toward which the UE should perform the RA procedure; and an indication of a beam of the second cell selected by the UE based on beam measurements obtained before or after performing the RA procedure. 47. The method of any of embodiments 33-46, wherein the first information comprises beam measurements associated with the RA procedure. 48. The method of embodiment 47, wherein the beam measurements comprise one or both of: beam measurements obtained when the UE is triggered to transmit a preamble for TA establishment for the LTM cell switch to the second cell; and beam measurements obtained when the UE receives an LTM cell switch command to perform the RA procedure for the LTM cell switch to the second cell. 49. The method of embodiment 47 or 48, wherein the beam measurements comprise one or more of: a signal strength value; a quality value; a cell identifier; a Reference Signal Received Power, RSRP; a Layer-1 RSRP; a Synchronization Signal RSRP; a Reference Signal Received Quality, RSRQ; a Signal to Interference plus Noise Ratio, SINR; a beam index; a beam identifier; and a Synchronization Signal Block, SSB, index. 50. The method of any of embodiments 33-49, wherein the first information comprises information relating to an LTM cell switch command for the LTM cell switch to the second cell. 51. The method of embodiment 50, wherein the information relating to the LTM cell switch command comprises one or more of: an indication of whether the LTM cell switch command allows reception of an RA response, RAR; an indication of whether the LTM cell switch command allows preamble retransmission; an indication of whether the LTM cell switch command allows power ramping; and an indication of whether the LTM cell switch command comprises timing advance, TA, information. 52. The method of any of embodiments 33-51, wherein the method further comprises: determining, based on the first information, that the RA procedure was for an LTM cell switch. 53. The method of any of embodiments 33-52, wherein the method further comprises: updating one or more timing advance, TA, acquisition procedures at the first network node based on the first information. 54. The method of any of embodiments 33-53, wherein the first cell is one of: a primary cell, PCell, for the UE; a primary cell of a secondary cell group, PSCell, for the UE; and a secondary cell, SCell, for the UE. 55. The method of any of embodiments 33-54, wherein the second cell is one or more of: a primary cell, PCell, for the UE; a primary cell of a secondary cell group, PSCell, for the UE; a secondary cell, SCell, for the UE; a cell of the first network node; and a cell of a different network node to the first cell. 56. The method of any of the previous embodiments, further comprising: obtaining user data; and forwarding the user data to a host or a user equipment. Group C Embodiments 57. A user equipment, comprising: processing circuitry configured to cause the user equipment to perform any of the steps of any of the Group A embodiments; and power supply circuitry configured to supply power to the processing circuitry. 58. A network node, the network node comprising: processing circuitry configured to cause the network node to perform any of the steps of any of the Group B embodiments; power supply circuitry configured to supply power to the processing circuitry. 59. A user equipment, UE, the UE comprising: an antenna configured to send and receive wireless signals; radio front-end circuitry connected to the antenna and to processing circuitry, and configured to condition signals communicated between the antenna and the processing circuitry; the processing circuitry being configured to perform any of the steps of any of the Group A embodiments; an input interface connected to the processing circuitry and configured to allow input of information into the UE to be processed by the processing circuitry; an output interface connected to the processing circuitry and configured to output information from the UE that has been processed by the processing circuitry; and a battery connected to the processing circuitry and configured to supply power to the UE. 60. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a network node in a cellular network for transmission to a user equipment (UE), the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE. 61. The host of the previous embodiment, wherein: the processing circuitry of the host is configured to execute a host application that provides the user data; and the UE comprises processing circuitry configured to execute a client application associated with the host application to receive the transmission of user data from the host. 62. A method implemented in a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: providing user data for the UE; and initiating a transmission carrying the user data to the UE via a cellular network comprising the network node, wherein the network node performs any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE. 63. The method of the previous embodiment, further comprising, at the network node, transmitting the user data provided by the host for the UE. 64. The method of any of the previous 2 embodiments, wherein the user data is provided at the host by executing a host application that interacts with a client application executing on the UE, the client application being associated with the host application. 65. A communication system configured to provide an over-the-top (OTT) service, the communication system comprising: a host comprising: processing circuitry configured to provide user data for a user equipment (UE), the user data being associated with the over-the-top service; and a network interface configured to initiate transmission of the user data toward a cellular network node for transmission to the UE, the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to transmit the user data from the host to the UE. 66. The communication system of the previous embodiment, further comprising: the network node; and / or the UE. 67. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to initiate receipt of user data; and a network interface configured to receive the user data from a network node in a cellular network, the network node having a communication interface and processing circuitry, the processing circuitry of the network node configured to perform any of the operations of any of the Group B embodiments to receive the user data from a user equipment (UE) for the host. 68. The host of the previous 2 embodiments, wherein: the processing circuitry of the host is configured to execute a host application that receives the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application. 69. The host of the any of the previous 2 embodiments, wherein the initiating receipt of the user data comprises requesting the user data. 70. A method implemented by a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: at the host, initiating receipt of user data from the UE, the user data originating from a transmission which the network node has received from the UE, wherein the network node performs any of the steps of any of the Group B embodiments to receive the user data from the UE for the host. 71. The method of the previous embodiment, further comprising at the network node, transmitting the received user data to the host. 72. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a cellular network for transmission to a user equipment (UE), wherein the UE comprises a communication interface and processing circuitry, the communication interface and processing circuitry of the UE being configured to perform any of the operations of any of the Group A embodiments to receive the user data from the host. 73. The host of the previous embodiment, wherein the cellular network further includes a network node configured to communicate with the UE to transmit the user data to the UE from the host. 74. The host of the previous 2 embodiments, wherein: the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application. 75. A method implemented by a host operating in a communication system that further includes a network node and a user equipment (UE), the method comprising: providing user data for the UE; and initiating a transmission carrying the user data to the UE via a cellular network comprising the network node, wherein the UE performs any of the operations of any of the Group A embodiments to receive the user data from the host. 76. The method of the previous embodiment, further comprising: at the host, executing a host application associated with a client application executing on the UE to receive the user data from the host application. 77. The method of the previous embodiment, further comprising: at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application, wherein the user data is provided by the client application in response to the input data from the host application. 78. A host configured to operate in a communication system to provide an over-the-top (OTT) service, the host comprising: processing circuitry configured to provide user data; and a network interface configured to initiate transmission of the user data to a cellular network for transmission to a user equipment (UE), wherein the UE comprises a communication interface and processing circuitry, the communication interface and processing circuitry of the UE being configured to perform any of the steps of any of the Group A embodiments to transmit the user data to the host. 79. The host of the previous embodiment, wherein the cellular network further includes a network node configured to communicate with the UE to transmit the user data from the UE to the host. 80. The host of the previous 2 embodiments, wherein: the processing circuitry of the host is configured to execute a host application, thereby providing the user data; and the host application is configured to interact with a client application executing on the UE, the client application being associated with the host application. 81. A method implemented by a host configured to operate in a communication system that further includes a network node and a user equipment (UE), the method comprising: at the host, receiving user data transmitted to the host via the network node by the UE, wherein the UE performs any of the steps of any of the Group A embodiments to transmit the user data to the host. 82. The method of the previous embodiment, further comprising: at the host, executing a host application associated with a client application executing on the UE to receive the user data from the UE. 83. The method of the previous 2 embodiments, further comprising: at the host, transmitting input data to the client application executing on the UE, the input data being provided by executing the host application, wherein the user data is provided by the client application in response to the input data from the host application.

Claims

CLAIMS 1. A method performed by a user equipment, UE, being served by a first cell of a first network node, the method comprising: performing (202) a random access, RA, procedure for a lower-layer triggered mobility, LTM, cell switch to a second cell; and determining (204) first information associated with the RA procedure for the LTM cell switch to the second cell.

2. The method of claim 1, further comprising transmitting, to a network node, at least some of the first information.

3. The method of claim 2, wherein the RA procedure is successful, and the network node to which the at least some of the first information is transmitted is a second network node serving the second cell.

4. The method of claim 2, wherein the RA procedure is unsuccessful, and the network node to which the at least some of the first information is transmitted is the first network node.

5. The method of any of claims 2-4, wherein the at least some of the first information is transmitted in a random access report.

6. The method of any of claims 2-4, wherein the at least some of the first information is transmitted in one or more of: a radio link failure, RLF, report; a successful handover report, SHR; a successful PSCell change report, SPR; an UEInformationResponse message; an SCGFailureInformation message; and an MCGFailureInformation message.

7. The method of any preceding claim, wherein the first information associated with the RA procedure comprises an indication that a purpose of the RA procedure is an LTM cell switch operation.

8. The method of any preceding claim, wherein the first information associated with the RA procedure comprises one or more of: an indication of what triggered the UE to perform the RA procedure; an indication that the RA procedure was performed responsive to a downlink control information, DCI, indication; and an indication of a power level applied by the UE during the RA procedure.

9. The method of any preceding claim, wherein the first information comprises information relating to one or more timing advance, TA, values associated with the RA procedure.

10. The method of claim 9, wherein the information relating to one or more TA values comprises one or more of: an indication of whether a random-access configuration received by the UE and to be used for acquiring a TA for the second cell allows reception of an RA response, RAR from the first cell; an indication of a minimum time interval between the UE receiving from the first cell a trigger for TA establishment and the UE performing the RA procedure for the LTM cell switch to the second cell; an indication of whether the UE stored a TA value received from the first cell for the second cell; an indication of whether there is any difference between a TA value that the UE received from the first cell for the second cell and a TA value that the UE received as part of an RA response message during the RA procedure; an indication of a difference between a TA value that the UE received from the first cell for the second cell and a TA that the UE received as part of an RA response message during the RA procedure; an indication of a TA value for the second cell that the UE received during the RA procedure; and an indication of TA values for one or more candidate cells for cell switch.

11. The method of any preceding claim, wherein the method further comprises: performing the RA procedure responsive to receiving a first indication to perform the RA procedure for the LTM cell switch to the second cell.

12. The method of claim 11, wherein the first indication comprises or is comprised in an LTM cell switch command for the LTM cell switch to the second cell.

13. The method of claim 12, wherein the first information comprises information relating to the LTM cell switch command.

14. The method of claim 13, wherein the information relating to the LTM cell switch command comprises one or more of: an indication of whether the LTM cell switch command allows reception of an RA response, RAR; an indication of whether the LTM cell switch command allows preamble retransmission; an indication of whether the LTM cell switch command allows power ramping; and an indication of whether the LTM cell switch command comprises timing advance, TA, information.

15. The method of any preceding claim, wherein the method further comprises: performing the RA procedure responsive to determining that a Random Access Channel less, RACH-less, LTM cell switch to the second cell has failed.

16. The method of claim 15, wherein determining that a RACH-less LTM cell switch to the second cell has failed comprises determining that a supervision timer has expired without the UE receiving a Physical Downlink Control Channel, PDCCH, transmission.

17. The method of any preceding claim, wherein performing the RA procedure comprises one or more of: transmitting an RA preamble to a second network node serving the second cell; receiving a timing advance command, TAC, for the LTM cell switch to the second cell; receiving a trigger for re-transmission of the RA preamble to the second network node serving the second cell; retransmitting the RA preamble to the second network node; receiving an RA response, RAR, from the second network node; receiving a timing advance, TA, value from the first network node; detecting contention; and selecting an RAR.

18. A method performed by a network node, wherein a user equipment, UE, is being served by a first cell of a first network node, the method comprising: receiving (302), from the UE, first information associated with a random access, RA, procedure for a lower-layer triggered mobility, LTM, cell switch to a second cell.

19. The method of claim 18, wherein the method further comprises: prior to receiving the first information, performing a random access, RA, procedure with the UE for the LTM cell switch of the UE to the second cell.

20. The method of claim 19, wherein performing the RA procedure comprises one or more of: receiving an RA preamble from the UE; transmitting a timing advance command, TAC, for the LTM cell switch to the second cell; transmitting a trigger for re-transmission of the RA preamble to the UE; receiving a retransmission of the RA preamble from the UE; and transmitting an RA response, RAR, to the UE.

21. The method of claim 19 or 20, wherein the RA procedure is successful, and the network node is a second network node serving the second cell.

22. The method of claim 18, wherein the network node is the first network node.

23. The method of any of claims 18-22, wherein the first information is received in a random access report.

24. The method of any of claims 18-22, wherein the first information is received in one or more of: a radio link failure, RLF, report; a successful handover report, SHR; a successful PSCell change report, SPR; an UEInformationResponse message; an SCGFailureInformation message; and an MCGFailureInformation message.

25. The method of any claims 18-24, wherein the first information associated with the RA procedure comprises an indication that a purpose of the RA procedure is an LTM cell switch operation.

26. The method of any of claims 18-25, wherein the first information associated with the RA procedure comprises one or more of: an indication of what triggered the UE to perform the RA procedure; an indication that the RA procedure was performed responsive to a downlink control information, DCI, indication; and an indication of a power level applied by the UE during the RA procedure.

27. The method of any of claims 18-26, wherein the first information comprises information relating to one or more timing advance, TA, values associated with the RA procedure.

28. The method of claim 27, wherein the information relating to one or more TA values comprises one or more of: an indication of whether a random-access configuration received by the UE and to be used for acquiring a TA towards the second cell allows reception of an RA response, RAR, from the first cell; an indication of a minimum time interval between the UE receiving from the first cell a trigger for TA establishment, and the UE performing the RA procedure for the LTM cell switch to the second cell; an indication of whether the UE stored a TA value received from the first cell for the second cell; an indication of whether there is any difference between a TA value that the UE received from the first cell for the second cell and a TA value that the UE received as part of an RA response message during the RA procedure; an indication of a difference between a TA value that the UE received from the first cell for the second cell and a TA value that the UE received as part of an RA response message during the RA procedure; an indication of a TA value for the second cell that the UE received during the RA procedure; and an indication of TA values for one or more candidate cells for cell switch.

29. The method of any of claims 18-28, wherein the first information comprises information relating to an LTM cell switch command for the LTM cell switch to the second cell.

30. The method of claim 29, wherein the information relating to the LTM cell switch command comprises one or more of: an indication of whether the LTM cell switch command allows reception of an RA response, RAR; an indication of whether the LTM cell switch command allows preamble retransmission; an indication of whether the LTM cell switch command allows power ramping; and an indication of whether the LTM cell switch command comprises timing advance, TA, information.

31. The method of any of claims 18-30, wherein the method further comprises: determining, based on the first information, that the RA procedure was for an LTM cell switch.

32. The method of any of claims 18-31, wherein the method further comprises: updating one or more timing advance, TA, acquisition procedures at the first network node based on the first information.

33. A user equipment (400) adapted to be served by a first cell of a first network node, the user equipment comprising processing circuitry and a memory, the memory containing instructions executable by the processing circuitry whereby the user equipment is operable to: perform (202) a random access, RA, procedure for a lower-layer triggered mobility, LTM, cell switch to a second cell; and determine (204) first information associated with the RA procedure for the LTM cell switch to the second cell.

34. The user equipment as claimed in claim 33 wherein the memory further contains instructions executable by the processing circuitry whereby the user equipment is operable to perform the method as claimed in any one of claims 2 to 17.

35. A network node (410, 420) comprising processing circuitry and a memory, the memory containing instructions executable by the processing circuitry whereby the network node is operable to: receive (302), from a UE being served by a first cell of a first network node, first information associated with a random access, RA, procedure for a lower-layer triggered mobility, LTM, cell switch to a second cell.

36. The network node as claimed in claim 35, wherein the memory further contains instructions executable by the processing circuitry whereby the network node is operable to perform the method as claimed in any one of claims 19 to 32.

37. A computer program, comprising instructions which, when executed on at least one processor, cause the at least one processor to carry out a method according to any of claims 1 to 32.

38. A computer-readable medium comprising instructions that, when executed on at least one processor, cause the at least one processor to perform the method according to any of claims 1 to 38.

39. A computer program product comprising non transitory computer readable media having stored thereon a computer program according to claim 37.

Images