Logging layer 1 (L1) measurement information

Abstract

A method is performed by a user equipment (UE) (700). The method comprises: responsive to detection of radio link failure (RLF) and / or failure of a mobility procedure, logging (402), in a data structure, Layer 1 (L1) measurement information. The L1 measurement information 5 comprises L1 measurements obtained by the UE from transmissions by one or more network entities. The one or more network entities comprise at least one neighbor network entity and / or at least one serving network entity of the UE preceding the RLF and / or the failure of the mobility procedure.

Description

LOGGING LAYER 1 (LI) MEASUREMENT INFORMATIONTECHNICAL FIELD

[0001] Embodiments of the disclosure relate to communication networks, and particularly to methods and apparatus for logging Layer 1 measurement information.BACKGROUNDLI / Layer 2 (L2) Triggered Mobility (LTM) support in the 3rdGeneration Partnership Project (3GPP) release 18

[0002] A high level description of an LTM operation can be found in 3 GPP Technical Specification (TS) 38.300 vl 8.0.0 (section 9.2.3.5). An excerpt is proposed below:LTM is a procedure in which a gNB receives LI measurement report(s) from a UE, and on their basis the gNB changes UE serving cell by a cell switch command signalled via a MAC CE. The cell switch command indicates an LTM candidate configuration that the gNB previously prepared and provided to the UE through RRC signalling. Then the UE switches to the target configuration according to the cell switch command. The LTM procedure can be used to reduce the mobility latency as described in Annex G.[...]The following principles apply to LTM:- Security key is maintained upon an LTM cell switch;- Subsequent LTM is supported.LTM supports both intra-gNB-DU and intra-gNB-CU inter-gNB-DU mobility. LTM supports both intra-frequency and inter -frequency mobility, including mobility to interfrequency cell that is not a current serving cell. LTM is supported only for licensed spectrum. The following scenarios are supported:- PCell change in non-CA scenario and non-DC scenario;- PCell and SCell(s) change in CA scenario;- Dual connectivity scenario, PCell and MCG SCell(s) change and intra-SN PSCell and SCG SCell(s) change without MN involvement. LTM for simultaneous PCell and PSCell change is not supported.While the UE has stored LTM candidate configurations the UE can also execute any L3 handover command sent by the network.

[0003] Figure 1 is a signaling diagram illustrating a signaling procedure for LTM, particularly a high level procedure for LTM. At step 102 of the procedure, a User Equipment (UE) is in a Radio Resource Control (RRC) connected state. At step 104, the UE transmits a measurement report to a gNB. At step 106, the gNB performs LTM candidate preparation. At step 108, the gNB transmits, to the UE, an RRC reconfiguration (an LTM candidate cell configuration). At step 112, Downlink (DL) synchronization with the candidate cells is performed between the UE and the gNB. At step 114, Uplink (UL) synchronization with the candidate cells is performed between the UE and the gNB. At step 116, the UE transmits, to the gNB, an LI measurement report. At step 118, the gNB makes an LTM decision. At step 120, the gNB transmits, to the UE, a cell switch command (a Media Access Control (MAC) Control Element (CE)). At step 112, the UE detaches from its source, and applies the target configurations. At step 124, a Random Access (RA) Channel (RACH) procedure is performed between the UE and the gNB. At step 126, LTM cell switch completion is performed between the UE and the gNB.

[0004] TS 38.401 vl8.1.0 describes intra- New Radio (NR) mobility when LTM is used with more detail concerning a gNB in split deployment, i.e.:- intra-gNB Distributed Unit (DU) (intra-gNB-DU) LTM (discussed in section 8.2. 1.4);- inter-gNB DU (inter-gNB-DU) LTM (discussed in section 8.2. 1.5); and- LTM with gNB Centralized Unit (CU) User Plane (UP) (gNB-CU-UP) change (discussed in section 8.2. 1.6).

[0005] Figure 2 is a signaling diagram illustrating a signaling procedure for intra-gNB-DU LTM. The signaling procedure begins with user data being shared between a UE and a gNB- DU and the gNB-DU and the gNB-CU. At step 202, Layer 3 (L3) measurement control and reports are performed. At step 204, the gNB-CU makes an LTM configuration decision. At step 206, the gNB-CU transmits, to the gNB-DU, a UE context modification request message. At step 208, the gNB-DU transmits, to the gNB-CU, a UE context modification response message. Step 210 is a repeat of step 206, and step 212 is a repeat of step 208. At step 214, the gNB-CU performs a DL RRC message transfer (RRCReconfiguration) towards the gNB-DU. At step 216, the gNB-DU transmits, to the UE, an RRCReconfiguration message. At step 218, the UE transmits, to the gNB-DU, an RRCReconfigurationComplete message. At step 220, the gNB-DU performs an UL RRC message transfer (RRCReconfigurationComplete) towards the gNB-CU. At step 222, the UE and gNB-DU perform an early Timing Advance (TA) acquisitionprocedure. At step 224, the UE transmits, to the gNB-DU, an LI measurement report.

[0006] At step 226, the gNB-DU makes an LTM Cell Switch Decision. At step 228, the gNB- DU transmits, to the UE, an LTM cell switch command. At step 230, the gNB-DU transmits, to the gNB-CU, a DU-CU cell switch notification (Target Cell ID) message. At step 232, the gNB-DU transmits, to the gNB-CU, a download data delivery status. At step 234, the gNB-DU detects UE access. At step 236, the gNB-DU transmits, to the gNB-CU, an access success (Target Cell ID) message. At step 238, the UE transmits, to the gNB-DU, an RRCReconfigurationComplete message. At step 240, the gNB-DU performs an UL RRC message transfer (RRCReconfigurationComplete) towards the gNB-CU. At step 242, the gNB- CU transmits, to the gNB-DU, a UE context modification request message (the prepared cells to be released). At step 244, the gNB-DU transmits, to the gNB-CU, a UE context modification response message. User data is then shared between the UE and gNB-DU and the gNB-DU and gNB-CU.

[0007] Figure 3 is a signaling diagram illustrating a signaling procedure for inter-gNB-DU LTM. The signaling procedure begins with user data being shared between a UE and a source gNB-DU and the source gNB-DU and the gNB-CU. At step 302, L3 measurement control and reports are performed. At step 304, the gNB-CU makes an LTM configuration decision. At step 306, the gNB-CU transmits, to a candidate gNB-DU, a UE context setup request message. At step 308, the candidate gNB-DU transmits, to the gNB-CU, a UE context setup response message. At step 310, the gNB-CU transmits, to the source gNB-DU, a UE context modification request message. At step 312, the source gNB-DU transmits, to the gNB-CU, a UE context modification response message. At step 314, the gNB-CU transmits, to the candidate gNB-DU, a UE context modification request message. At step 314, the candidate gNB-DU transmits, to the gNB-CU, a UE context modification response message. At step 318, the gNB-CU performs a DL RRC message transfer (RRCReconfiguration) towards the source gNB-DU. At step 320, the source gNB-DU transmits, to the UE, an RRCReconfiguration message. At step 322, the UE transmits, to the source gNB-DU, an RRCReconfigurationComplete message. At step 324, the source gNB-DU performs an UL RRC message transfer (RRCReconfigurationComplete) towards the gNB-CU. At step 326, the UE and source gNB-DU perform an early TA acquisition procedure, and this information is shared with the candidate gNB-DU. At step 328, the candidate gNB-DU performs DU-CU cell TA information transfer towards the gNB-CU. At step 330, the gNB-CU performs CU-DU cell TA information transfer towards the source gNB-DU. At step 332, the UE transmits, to thesource gNB-DU, an LI measurement report.

[0008] At step 334, the source gNB-DU makes an LTM Cell Switch Decision. At step 336, the source gNB-DU transmits, to the UE, an LTM cell switch command. At step 338, the source gNB-DU transmits, to the gNB-CU, a DU-CU cell switch notification (Target Cell ID, Transmission Configuration Indication (TCI) state ID) message. At step 340, the gNB-CU transmits, to the candidate gNB-DU, a CU-DU cell switch notification (Target Cell ID, TCI state ID) message. At step 342, the source gNB-DU transmits, to the gNB-CU, a download data delivery status. At step 344, the candidate gNB-DU detects UE access. At step 346, the candidate gNB-DU transmits, to the gNB-CU, an access success (Target Cell ID) message. At step 348, the UE transmits, to the candidate gNB-DU, an RRCReconfigurationComplete message. At step 350, the candidate gNB-DU performs an UL RRC message transfer (RRCReconfigurationComplete) towards the gNB-CU. At step 352, the gNB-CU transmits, to the source gNB-DU, a UE context release command (the prepared cells to be released). At step 354, the source gNB-DU transmits, to the gNB-CU, a UE context release complete message. User data is then shared between the UE and the candidate gNB-DU and the candidate gNB- DU and the source gNB-CU.Mobility Robustness Optimisation (MRO) in Self-Organized Network (SON)

[0009] Mobility Robustness Optimisation (MRO) aims at detecting and enabling correction of one or more of the following problems:- Connection failure due to intra-system or inter-system mobility;- Inter-system Unnecessary Handover (HO) (e.g., too early inter-system HO from NR to Evolved Universal Terrestrial Radio Access Network (E-UTRAN) with no Radio Link Failure (RLF));- Inter-system HO ping-pong;- Primary Secondary Cell (SCell) (PSCell) change failure;- Inter-system voice fallback failure;- Fast Master Cell Group (MCG) recovery failure.

[0010] MRO provides means to distinguish the above problems from NR coverage related problems and other problems not related to mobility.

[0011] For detection of a sub-optimal successful handover, MRO additionally enables observability of:- Successful HO due to intra-NR mobility; and- Successful HO due to inter- Radio Access Technology (RAT) mobility.

[0012] For detection of a sub-optimal successful PSCell addition / change, MRO additionally enables observability of:- Successful PSCell addition / change.MRO reports andLTM

[0013] One of the main objectives of the SON / Minimization of Drive Tests (MDT) enhancement Work Item (WI) in Release 19 Work Item Description (WID) [RP-234038] is to enhance the MRO features to optimize the LTM cell switch procedure, specifically:MRO enhancement for Release 18 mobility mechanisms, including, Lower layer triggered mobility (LTM), Conditional Handover (CHO) with candidate Secondary Cell Groups (SCGs), subsequent Conditional PSCell Addition and Change (CPAC) [RAN 3, RAN 2]: o Specification of the inter-node information exchange, including possible enhancements to interfaces [RAN3 ] o Identify and specify necessary UE reporting to enhance the mobility parameter tuning [RAN2 ]SUMMARY

[0014] There currently exist certain challenge(s). In RAN2 #126 meeting, the following agreement was reached:If available, log the LI measurements for serving cell, target cell and other LTM candidate cells in RLE report, upon RLE or mobility failure.

[0015] Based on this agreement, available LI measurements can be logged in an RLF report. However, how to log the LI measurements in the RLF report still needs to be solved. Moreover, if available LI measurements are also logged in other SON reports, e.g. Successful Handover Report (SHR) or Successful PSCell Report (SPR), then a similar problem relating to how to log LI measurements for other SON reports should also be considered.

[0016] In RAN2#127 meeting, one agreement regarding an LTM candidate cell indication was:We aim to log some info to deduce the ItmCandidate (similar like choCandidate) in SHR to indicate whether a neighbour cell is an LTM candidate cell or not, TBD ifexplicit / implicit.

[0017] Based on this agreement, an explicit / implicit indication on the LTM candidate cell should be logged. However, the problem of whether to use an explicit or implicit indication is not yet solved; under what conditions should the indication be explicit or implicit is also not settled.

[0018] Another agreement in RAN2#127 meeting was regarding RACH access type:RAN 2 include the specific access type in the RLF report, i.e. whether it is RA-based or RA-less cell switch. FFS details, e.g. if explicit or implicitly signalled.

[0019] Similarly, how to indicate the RACH access type needs to be worked out.

[0020] Embodiments of the present disclosure help solve one or more of the above- mentioned problems. There is also disclosed an implementation example of discussed embodiments.

[0021] Certain aspects of the disclosure and their embodiments may provide solutions to these or other challenges.

[0022] In a first aspect of the disclosure, there is provided a method performed by a UE. The method comprises: responsive to detection of radio link failure (RLF) and / or failure of a mobility procedure, logging, in a data structure, Layer 1 (LI) measurement information. The LI measurement information comprises LI measurements obtained by the UE from transmissions by one or more network entities. The one or more network entities comprise at least one neighbor network entity and / or at least one serving network entity of the UE preceding the RLF and / or the failure of the mobility procedure.

[0023] In a second aspect of the disclosure, there is provided a method performed by a network node. The method comprises: receiving from a User Equipment (UE), a report comprising a data structure comprising LI measurement information. The LI measurement information is logged in the data structure responsive to a radio link failure (RLF) and / or failure of a mobility procedure detected by the UE. The LI measurement information comprises LI measurements obtained by the UE from transmissions by one or more network entities. The one or more network entities comprise at least one neighbor network entity and / or at least one serving network entity of the UE preceding the RLF and / or the failure of the mobility procedure.

[0024] In a third aspect of the disclosure, there is provided a UE comprising processing circuitry configured to cause the UE to, responsive to detection of radio link failure (RLF) and / or failure of a mobility procedure, log, in a data structure, Layer 1 (LI) measurementinformation. The LI measurement information comprises LI measurements obtained by the UE from transmissions by one or more network entities. The one or more network entities comprise at least one neighbor network entity and / or at least one serving network entity of the UE preceding the RLF and / or the failure of the mobility procedure.

[0025] In a fourth aspect of the disclosure, there is provided a UE adapted to, perform a method according to embodiments of the first aspect.

[0026] In a fifth aspect of the disclosure, there is provided a network node comprising processing circuitry configured to cause the network node to receive from a User Equipment (UE), a report comprising a data structure comprising LI measurement information. The LI measurement information is logged in the data structure responsive to a radio link failure (RLF) and / or failure of a mobility procedure detected by the UE. The LI measurement information comprises LI measurements obtained by the UE from transmissions by one or more network entities. The one or more network entities comprise at least one neighbor network entity and / or at least one serving network entity of the UE preceding the RLF and / or the failure of the mobility procedure.

[0027] In a sixth aspect of the disclosure, there is provided a network node adapted to perform a method according to embodiments of the second aspect.

[0028] In a seventh aspect of the disclosure, there is provided a computer-readable storage medium storing code which, when executed by processing circuitry of a UE, causes the UE to perform a method according to embodiments of the first aspect.

[0029] In an eighth aspect of the disclosure, there is provided a computer-readable storage medium storing code which, when executed by processing circuitry of a network node, causes the network node to perform a method according to embodiments of the second aspect.

[0030] Embodiments of the present disclosure facilitate the enhancement of RLF reports, SHR, SPR or any other newly introduced MRO report regarding on how LI measurement results, LTM candidate cell indication(s), and indication information on RACH-less or RACH- based LTM are reported. The methods disclosed herein, and the introduced / updated information elements discussed herein, ensure that any one or more of LI measurement results, LTM candidate cell indication(s), and indication information on RACH-less or RACH-based LTM can be logged in the MRO report for LTM mobility optimization purposes.

[0031] Certain embodiments may provide one or more of the following technical advantage(s). Embodiments disclosed in the present disclosure enable the UE to log any one or more of LI measurement results, LTM candidate cell indication(s), and indicationinformation on RACH-less or RACH-based LTM in an MRO report. The transmission of such information enables the network to optimize its future LTM cell switch related decisions. The network can use this information to figure out the root cause for the LTM failure and near failure case. The teachings of certain embodiments may improve the performance (e.g., efficiency, reliability, etc.) of LTM and other mobility procedures in the network.BRIEF DESCRIPTION OF THE DRAWINGS

[0032] 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:

[0033] Figure 1 illustrates a signalling procedure for LTM;

[0034] Figure 2 illustrates a signaling procedure for intra-gNB-DU LTM;

[0035] Figure 3 illustrates a signaling procedure for inter-gNB-DU LTM;

[0036] Figure 4 is a flow chart illustrating a method in accordance with some embodiments;

[0037] Figure 5 is a flow chart illustrating a method in accordance with some embodiments;

[0038] Figure 6 shows an example of a communication system in accordance with some embodiments;

[0039] Figure 7 shows a UE in accordance with some embodiments;

[0040] Figure 8 shows a network node in accordance with some embodiments; and

[0041] Figure 9 is a block diagram illustrating a virtualization environment in which functions implemented by some embodiments may be virtualized.DETAILED DESCRIPTION

[0042] 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.

[0043] In the present disclosure, a UE may refer to any device using the service of a wireless network. A network node may refer to a node capable of providing services to a UE. Some embodiments below are described for L1 / L2 Triggered Mobility in NR, but can be extended to other RATs (e.g., to 6thGeneration (6G)).

[0044] The embodiments disclosed herein are applicable to all scenarios of LTM, including e.g. Primary Cell (PCell) change PSCell change and SCell change.

[0045] The LTM configuration provided to a UE may include one or more LTM candidatetarget cell(s), wherein the UE (and the target gNB-DU) is prepared for a potential LTM cell switch to any of the one or more candidate target cell(s). Herein, such a candidate target cell may be referred to as a “candidate target cell”, “LTM candidate target cell”, “candidate LTM target cell”, “candidate cell”, “LTM candidate cell”, “candidate LTM cell”, “LTM switch candidate cell”, “LTM switch candidate” or “LTM cell switch candidate”. Collectively, the one or more candidate target cell(s) may also be referred to as “LTM candidate list”, “LTM candidate cell list” or “LTM cell switch candidate list”.

[0046] Herein, reporting measurements (e.g. LI measurements or L3 measurements) are regarded as equivalent to reporting measurement results (e.g. LI measurement results or L3 measurement results).

[0047] In this disclosure, methods are described by taking NR as the radio technology of reference. This should be considered as non-limiting as the methods herein apply to any radio access technology where LTM mobility is supported, e.g. a future 6G radio access technology (e.g. based on a standard specified by 3GPP).

[0048] For example, whilst embodiments disclosed herein may be discussed with reference to cells (e.g., candidate cells, measurements performed for cells, mobility between cells, etc.), it should be understood that the embodiments are also applicable to non-cellular networks. That is, the skilled person would understand that embodiments of the present disclosure are applicable to any network in which a UE receives transmissions from a network entity, from which LI measurements can be obtained, whether that network entity is a network node (e.g., a base station or base station component), a cell, a beam, or any other logical network entity.

[0049] The methods proposed in this disclosure are not limited to LTM mobility procedures. For example, the methods or parts of the methods can also apply to the normal L3 handover, or mobility procedure for non-terrestrial networks (NTNs). As such, the term “LTM mobility procedure”, as used herein, can be generalized to include and / or refer to any such mobility procedure.

[0050] The embodiments disclosed herein are described mainly focusing on Reference Signal Received Power (RSRP) as the measurement quantity of the concerned LI measurements (i.e. Ll-RSRP). However, the embodiments disclosed herein are applicable also for measurement, logging and reporting of other LI measurement quantities, such as LI- Reference Signal / Symbol Received Quality (RSRQ) or LI- Signal -to-Interference-plus-Noise Ratio (SINR).

[0051] The embodiments disclosed herein are further described mainly focusing on reportingLI measurement results in the RLF report. However, the embodiments, methods, options and examples described herein can also be applied to the SHR, the SPR or any other MRO reports (or any other SON reports).

[0052] When it is herein described that a UE logs some data, e.g. logs measurement results, (e.g., in a report) this means that it stores the data in a data structure that is prepared for inclusion and transmission of a (e.g., MRO or SON) report, and that the UE subsequently may send the (e.g., MRO or SON) report to the network, e.g. if requested by the network to do so.

[0053] As used herein, a neighbor network entity may refer to a neighbor cell, a neighbor network node, or one or more beams (e.g., Channel State Information (CSI) Reference Signal (RS)) of a neighbor network node (e.g., of the UE). A serving network entity may refer to a serving cell, a serving network node, or one or more beams (e.g., CSI-RS) of a serving network node (e.g., of the UE).

[0054] As used herein, a candidate network entity for a mobility procedure may be a cell, a network node, or a beam of a network node. For example, a candidate serving network entity for a mobility procedure may be a serving cell, a serving network node, or a beam of a serving network node. A candidate neighbor network entity for a mobility procedure may be a neighbor cell, a neighbor network node, or a beam of a neighbor network node.

[0055] As used herein, the term “near failure” of a mobility procedure (also referred to as a “sub-optimal” mobility procedure) may refer to a mobility procedure that is successful but which also meets one or more “near-failure” criteria. For example, the one or more near failure criteria may include any one or more of: the mobility procedure taking longer than a threshold amount of time to be completed, the mobility procedure resulting in more than a threshold number of dropped data packets, the mobility procedure resulting in one or more dropped services, service in a target cell being worse after the mobility procedure than service in a source cell (or below some threshold), and the mobility procedure involving more than a threshold number of failed access (e.g. RACH) attempts. Information regarding a near failure of a mobility procedure may be included in an SHR or SPR transmitted to a network node.

[0056] As used herein, “available measurements” may refer to measurements that have been obtained by the UE in a measurement period. Similarly, “available measured cells” may refer to cells for which measurements have been obtained by the UE in a measurement period.

[0057] As used herein, a “last serving” network entity (e.g., a last serving cell) may refer to a network entity of the UE (directly) preceding (i.e., before) the RLF and / or the failure or near failure of a mobility procedure.

[0058] Figure 4 depicts a method in accordance with particular embodiments. The method of Figure 4 may be performed by a UE or wireless device (e.g. the UE 612 or UE 700 as described later with reference to Figures 6 and 7 respectively). The method begins at step 402 in which, responsive to detection of RLF and / or failure or near failure of a mobility procedure, the UE logs, in a data structure, LI measurement information. For example, the mobility procedure may be an LTM procedure.

[0059] The LI measurement information may comprise LI measurements (e.g., RSRP measurements) obtained by the UE from transmissions (e.g., Synchronization Signal Block (SSBs)) by one or more network entities. The one or more network entities may comprise: at least one neighbor network entity; and / or at least one serving network entity of the UE preceding the RLF and / or the failure or near failure of the mobility procedure.

[0060] For example, the method of Figure 4 may further comprise obtaining the LI measurements. The UE may obtain the LI measurements by performing at least one LI measurement procedure on the transmissions by the one or more network entities.

[0061] The LI measurements may be logged in the data structure based on whether the at least one neighbor network entity and / or the serving network entity are candidate network entities for the mobility procedure. Alternatively, the LI measurements may be logged in the data structure regardless of whether the at least one neighbor network entity and / or the serving network entity are candidate network entities for the mobility procedure.

[0062] The LI measurement information may include LI measurements obtained by the UE from transmissions by the serving network entity regardless of whether the serving network entity is configured as a candidate network entity for the mobility procedure and / or whether a configuration for LI measurement reporting requires LI measurement reporting for the serving network entity (e.g., whether spCelllnclusion is set). Alternatively, the LI measurement information may include LI measurements obtained by the UE from transmissions by the serving network entity based on whether the serving network entity is configured as a candidate network entity for the mobility procedure and / or whether a configuration for LI measurement reporting requires LI measurement reporting for the serving network entity (e.g., whether spCelllnclusion is set).

[0063] The LI measurements may include all, or a subset of, a set of LI measurements obtained by the UE in a measurement period. For example, the subset may include one or more LI measurements of the set based on any one or more of: the one or more LI measurements meeting a threshold value; the one or more LI measurements having been obtained for anetwork entity for which the UE has obtained L3 measurements; the one or more LI measurements having been obtained for a network entity for which the UE has not obtained L3 measurements; the one or more LI measurements having been obtained for a network entity specified by a RRC configuration for LI measurement reporting (e.g., specified by nrOfReportedCells, nrOfReportedRS-PerCell and / or spCelllnclusion in LTM-CSI- ReportConflgy, a maximum number of LI measurements and / or L3 measurements allowed to be logged in the data structure; and a maximum number of network entities for which LI measurements and / or L3 measurements are allowed to be logged in the data structure.

[0064] For more detail on the above embodiments discussing the inclusion of the LI measurements in the LI measurement information, see the section entitled “Logging LI measurement results” below (particularly the sub-sections entitled “which LI measurement results should be logged” and “LI measurement results for the serving cell”).

[0065] Logging the LI measurement information in the data structure may comprise ordering the LI measurements in the data structure based on any one or more of: values of the LI measurements; values of L3 measurements obtained by the UE from transmissions by the one or more network entities; and whether the one or more network entities are candidate network entities for the mobility procedure. For more detail, see the section entitled “Logging LI measurement results” below (particularly the sub-sections entitled “LI measurement results for the neighboring LTM candidate cells” and “LI measurement results for the serving cell”).

[0066] The LI measurements logged in the data structure may be based on a mapping of measured values to reported values. For more detail, see the section entitled “Logging LI measurement results” below (particularly the sub-section entitled “LI measurement result, Ll- RSRP value and differential Ll-RSRP”).

[0067] Returning to step 402, additionally or alternatively to the LI measurement information including LI measurements, the LI measurement information may include: a first indication of whether a serving network entity of the UE preceding the RLF and / or the failure or near failure of the mobility procedure is a candidate network entity for the mobility procedure; and / or a second indication of whether a neighbor network entity of the UE is a candidate network entity for the mobility procedure. The first indication may be referred to herein as a “Indication of whether last serving cell is LTM candidate cell or not” and / or the second indication may also referred to herein as “Indication of whether a neighboring cell is LTM candidate cell or not”.

[0068] For more detail on the first and second indications, see the section entitled “LoggingLTM cell indications” below (particularly the sub-sections entitled “Indication of whether last serving cell is LTM candidate cell or not” and “Indication of whether a neighboring cell is LTM candidate cell or not”).

[0069] The first indication may be explicit or implicit. For example, the first indication may be explicit if the LI measurement information does not include LI measurements obtained from transmissions by the serving network entity. Alternatively, the first indication may be explicit regardless of whether the LI measurement information includes LI measurements obtained from transmissions by the serving network entity.

[0070] The first indication may be implicit if the LI measurement information includes LI measurements obtained by the UE from transmission by the serving network entity.

[0071] Similarly, the second indication may be explicit or implicit. For example, the second indication may be explicit if the LI measurement information does not include LI measurements obtained by the UE from transmissions by the neighbor network entity. Alternatively, the second indication may be explicit regardless of whether the LI measurement information includes LI measurements obtained by the UE from transmissions by the neighbor network entity.

[0072] The second indication may be implicit if the LI measurement information includes LI measurements obtained by the UE from transmissions by the neighbor network entity.

[0073] Returning to step 402, additionally or alternatively to the LI measurement information including any one or more of LI measurements, the first indication, and the second indication, the LI measurement information may include a third indication of an access type for a serving network entity of the UE preceding the RLF and / or the failure or near failure of the mobility procedure (e.g., following a first network entity switch being successfully performed for the serving network entity, where the first network entity switch may be successfully performed before the RLF). The third indication may indicate that the access type for the serving network entity is RACH-less or RACH-based. The third indication may be referred to herein as an “Indication of access type”.

[0074] For more detail on the third indication, see the section entitled “Logging access type, whether RACH-based or RACH-less LTM” below (particularly the sub-section entitled “Indication of access type and conditions for this indication”).

[0075] The third indication may be explicit or implicit. For example, the third indication may be implicit if the LI measurement information is logged in the data structure responsive to T304 expiry. For more detail, see the section entitled “Logging access type, whether RACH-based or RACH-less LTM” below (particularly the sub-section entitled “Indication of access type in SHR”).

[0076] The third indication may be explicit if the LI measurement information is logged in the data structure responsive to a cause other than T304 expiry. Alternatively, the third indication may be explicit regardless of the cause of the LI measurement information being logged in the data structure. For more detail, see the section entitled “Logging access type, whether RACH-based or RACH-less LTM” below (particularly the sub-sections entitled “Indication of access type in SHR” and “Explicit indication of access type”).

[0077] Returning to the method of Figure 4, the method may further comprise logging, in the data structure, an indication of a location of the UE when the UE performs a procedure for obtaining a TA estimation for a RACH-less mobility procedure. For example, the procedure may comprise the UE performing a TA measurement procedure or transmitting a preamble towards a candidate network entity for the RACH-less mobility procedure. For more detail, see the section below entitled “Logging location information when TA is estimated”.

[0078] At step 404, the UE may transmit, to a network node, a report comprising at least part of the data structure. In some embodiments, the data structure may be included in the report in its entirety. For example, the report may be an MRO report (such as an RLF report, an SHR report, or an SPR report) or a SON report. The report may comprise measurement information for multiple different RLFs, HO failures and / or near failures. For example, the report may comprise multiple data structures, each data structure comprising LI measurement information relating to a particular one or more RLFs, mobility failures or near failures. The report may be transmitted to the network node responsive to one or more triggers that are the same as or different to the triggers for logging the measurement information in the data structure (e.g., in response to a request from the network node, periodically, in response to the number of logged data structures or the amount of logged data meeting a threshold, etc).

[0079] Figure 5 depicts a method in accordance with particular embodiments. The method of Figure 5 may be performed by a network node (e.g. the network node 610 or network node 800 as described later with reference to Figures 6 and 8 respectively). The method begins at step 502 in which the network node receives, from a UE, a report comprising a data structure comprising LI measurement information. The LI measurement information is logged in the data structure responsive to a RLF and / or failure or near failure of a mobility procedure detected by the UE. For example, the mobility procedure may be an LTM procedure. The report may be an MRO report (such as an RLF report, a SHR report, or a SPR report) or a SON report.

[0080] The report may comprise LI measurement information for multiple different RLFs, HO failures and / or near failures. For example, the report may comprise multiple data structures, each data structure comprising LI measurement information relating to a particular one or more RLFs, mobility failures or near failures. The report may be transmitted by the UE responsive to one or more triggers that are the same as or different to the triggers for logging the measurement information in the data structure.

[0081] The LI measurement information may comprise LI measurements (e.g., RSRP measurements) obtained by the UE from transmissions (e.g., SSBs) by one or more network entities. The one or more network entities may comprise at least one neighbor network entity and / or at least one serving network entity of the UE preceding the RLF and / or the failure or near failure of the mobility procedure.

[0082] The LI measurements may be included in the LI measurement information based on whether the at least one neighbor network entity and / or the serving network entity are candidate network entities for the mobility procedure. Alternatively, the LI measurements may be included in the LI measurement information regardless of whether the at least one neighbor network entity and / or the serving network entity are candidate network entities for the mobility procedure.

[0083] The LI measurement information may include LI measurements obtained by the UE from transmissions by the serving network entity regardless of whether the serving network entity is configured as a candidate network entity for the mobility procedure and / or whether a configuration for LI measurement reporting requires LI measurement reporting for the serving network entity (e.g., whether spCelllnclusion is set). Alternatively, the LI measurement information may includes LI measurements obtained by the UE from transmissions by the serving network entity based on whether the serving network entity is configured as a candidate network entity for the mobility procedure and / or whether a configuration for LI measurement reporting requires LI measurement reporting for the serving network entity (e.g., whether spCelllnclusion is set).

[0084] The LI measurements may include all, or a subset of, a set of LI measurements obtained by the UE in a measurement period. For example, the subset may include one or more LI measurements of the set based on any one or more of: the one or more LI measurements meeting a threshold value; the one or more LI measurements having been obtained for a network entity for which the UE has obtained Layer 3, L3, measurements; the one or more LI measurements having been obtained for a network entity for which the UE has not obtained L3measurements; the one or more LI measurements having been obtained for a network entity specified by an RRC configuration for LI measurement reporting (e.g., specified by nrOfReportedCells, nrOfReportedRS-PerCell and / or spCelllnclusion in LTM-CSI- ReportConflgy, a maximum number of LI measurements and / or L3 measurements allowed to be logged in the data structure; and a maximum number of network entities for which LI measurements and / or L3 measurements are allowed to be logged in the data structure.

[0085] For more detail on the above embodiments discussing the inclusion of the LI measurements in the LI measurement information, see the section entitled “Logging LI measurement results” below (particularly the sub-sections entitled “which LI measurement results should be logged” and “LI measurement results for the serving cell”).

[0086] Logging the LI measurement information may comprise ordering the LI measurements in the data structure based on any one or more of: values of the LI measurements; values of L3 measurements obtained by the UE from transmissions by the one or more network entities; and whether the one or more network entities are candidate network entities for the mobility procedure. For more detail, see the section entitled “Logging LI measurement results” below (particularly the sub-sections entitled “LI measurement results for the neighboring LTM candidate cells” and “LI measurement results for the serving cell”).

[0087] The LI measurements included in the LI measurement information may be based on a mapping of measured values to reported values. For more detail, see the section entitled “Logging LI measurement results” below (particularly the sub-section entitled “LI measurement result, Ll-RSRP value and differential Ll-RSRP”).

[0088] Returning to step 502, additionally or alternatively to the LI measurement information including LI measurements, the LI measurement information may include a first indication of whether a serving network entity of the UE preceding the RLF and / or the failure or near failure of the mobility procedure is a candidate network entity for the mobility procedure; and / or a second indication of whether a neighbor network entity of the UE is a candidate network entity for the mobility procedure. The first indication may be referred to as an “Indication of whether last serving cell is LTM candidate cell or not” and / or the second indication may be referred to herein as an “Indication of whether a neighboring cell is LTM candidate cell or not”.

[0089] For more detail on the first and second indications, see the section entitled “Logging LTM cell indications” below (particularly the sub-sections entitled “Indication of whether last serving cell is LTM candidate cell or not” and “Indication of whether a neighboring cell isLTM candidate cell or not”).

[0090] The first indication may be explicit or implicit. For example, the first indication may be explicit if the LI measurement information does not include LI measurements obtained from transmissions by the serving network entity. Alternatively, the first indication may be explicit regardless of whether the LI measurement information includes LI measurements obtained from transmissions by the serving network entity.

[0091] The first indication may be implicit if the LI measurement information includes LI measurements obtained by the UE from transmission by the serving network entity.

[0092] Similarly, the second indication may be explicit or implicit. For example, the second indication may be explicit if the LI measurement information does not include LI measurements obtained by the UE from transmissions by the neighbor network entity. Alternatively, the second indication may be explicit regardless of whether the LI measurement information includes LI measurements obtained by the UE from transmissions by the neighbor network entity.

[0093] The second indication may be implicit if the LI measurement information includes LI measurements obtained by the UE from transmissions by the neighbor network entity.

[0094] Returning to step 502, additionally or alternatively to the LI measurement information including any one or more of LI measurements, the first indication, and the second indication, the LI measurement information may include a third indication of an access type for a serving network entity of the UE preceding the RLF and / or the failure or near failure of the mobility procedure (e.g., following a first network entity switch being successfully performed for the serving network entity, where the first network entity switch may be successfully performed before the RLF). The third indication may indicate that the access type for the serving network entity is RACH-less or RACH-based. The third indication may be referred to herein as an “Indication of access type”.

[0095] For more detail on the third indication, see the section entitled “Logging access type, whether RACH-based or RACH-less LTM” below (particularly the sub-sections entitled “Indication of access type and conditions for this indication”).

[0096] The third indication may be explicit or implicit. For example, the third indication may be implicit if the LI measurement information is logged in the data structure responsive to T304 expiry. For more detail, see the section entitled “Logging access type, whether RACH- based or RACH-less LTM” below (particularly the sub-section entitled “Indication of access type in SHR”).

[0097] The third indication may be explicit if the LI measurement information is logged in the data structure responsive to a cause other than T304 expiry. Alternatively, the third indication may be explicit regardless of the cause of the LI measurement information being logged in the data structure. For more detail, see the section entitled “Logging access type, whether RACH-based or RACH-less LTM” below (particularly the sub-sections entitled “Explicit indication of access type” and “Indication of access type in SHR”).

[0098] For the method of Figure 5, the data structure may further comprise an indication of a location of the UE when the UE performs a procedure for obtaining a TA estimation for a RACH-less mobility procedure. For example, the procedure may comprise the UE performing a TA measurement procedure or transmitting a preamble towards a candidate network entity for the RACH-less mobility procedure. For more detail on the indication of the location of the UE when the UE obtains the TA estimation, see the section below entitled “Logging location information when TA is estimated”.

[0099] At step 504, the network node may determine one or more parameters for handover and / or a configuration of a network based on the LI measurement information. For example, the one or more parameters may comprise Handover Control Parameters (HCP), such as a Time-to-Trigger (TTT) parameter (i.e., the time duration that the UE’s signal quality needs to meet a handover threshold before a handover is triggered), a Handover Margin (Hysteresis) (i.e., the margin by which a target cell’s signal strength must exceed that of a source cell before handover is initiated), an Event A3 parameter (i.e., the main handover triggering event where a UE initiates a handover when a target cell signal quality becomes better than a source cell by a defined offset (A3 offset)), and an Event A1 / A2 parameter (i.e., events related to entry and exit thresholds for signal strength, used to determine when the UE should remain connected to the serving cell or prepare for cell reselection). Additionally or alternatively, the one or more parameters may comprise network parameters that can be optimized for SONs, such as quality parameters, coverage parameters, capacity bandwidth parameters, interference parameters, and handoff parameters.

[0100] The method of Figure 5 may further comprise the network node sending, to the UE, a request for the report (e.g., prior to receiving the report). In such a case, the report may be transmitted to the network node by the UE in response to receiving the request.Logging LI measurement resultsWhich LI measurement results should be logged

[0101] The LI measurements (e.g., the LI measurements discussed above in relation to Figure 4 and 5) can be logged in an RLF report for all the available LI measured LTM candidate cells and all the measured SSB and CSI / RS beams.

[0102] Alternatively, the LI measurements can be logged in an RLF report for a subset (e.g., the subset discussed above in relation to Figures 4 and 5) of cells or beams among all the available LI measured LTM candidate cells and / or all the measured SSB and CSI / RS beams. For example, some conditions to limit the subset of the measurement reports are listed below:• Only the LI measurement results for those cells or beams with the LI measurement results (e.g. RSRP) higher than a predefined threshold,• Only the LI measurement results for those cells or beams with L3 measurement results,• Only the LI measurement results for those cells or beams without L3 measurement results,• The subset of the LI measured cells or beams based on RRC configuration for LI measurement reporting by UCI, i.e. limited by nrOfReportedCells , nrOfReportedRS- P er Cell and / or spCelllnclusion in LTM-CSI-ReportConflg.• The total number of the cells with the existing L3 measurement results and the cells with LI measurement results should not exceed a predefined number.

[0103] If both LI measurement results and L3 measurement results are included in a SON report and they share a maximum number of measurement results to be reported, e.g. maximum 8, then the UE may report an equal number of LI measurement results and L3 measurement results, e.g. 4 of each, so that the maximum number is not exceeded. Alternatively, it may be left to UE implementation to determine the number of LI measurement results and the number of L3 measurement results to include in the SON report, as long as the maximum number is not exceeded.

[0104] If both LI measurement results and L3 measurement results are included in a SON report and a restriction to a maximum number of cells for which measurement results may be reported, e.g. 8, applies to LI measurement results and L3 measurement results together, then the UE may report LI measurement results for an equal number of cells as the number of cells that it reports L3 measurement results for. Alternatively, it may be left to UE implementation to determine the number of cells for which it reports LI measurement results and the number of cells for which it reports L3 measurement results in the SON report, as long as the maximum number is not exceeded.

[0105] In some embodiments, a UE may report LI measurement results (i.e. include LImeasurement results in a SON report) also for neighbor cells and / or neighbor beams (i.e. beams in neighbor cells) which are not candidate LTM cells or candidate LTM beams.LI measurement results for the serving cell

[0106] In some embodiments, the LI measurements for the last serving cell may always be logged (e.g., in a data structure) no matter if the serving cell is configured as a LTM candidate cell or what the configuration of spCelllnclusion is.

[0107] Alternatively, the LI measurements for the last serving cell may only be logged (e.g., in the data structure) if the last serving cell is configured as an LTM candidate cell. In this alternative, the LI measurement results for the last serving cell may, as one option, be logged separately from the LI measurement results for neighbor cells. As another option, the LI measurement results for the last serving cell may be logged together with the LI measurement results for neighbor cells, either with only neighbor cells that are candidate LTM cells or with neighbor cells which may or may not be candidate LTM cells.

[0108] In another option, the LI measurements for the last serving cell may only be logged if the serving cell is configured as an LTM candidate cell and when spCelllnclusion is set.

[0109] The last serving cell may refer to a source PCell (in case HO failure or LTM cell switch failure), a source PSCell (in case of PSCell Addition failure, PSCell Cange failure or LTM for adding or changing a PSCell), or a PCell (in case RLF).

[0110] Beam level LI measurements for last serving cell may be sorted based on the Ll- RSRP, e.g. the beam with the highest LI SS / PBCH block RSRP may be listed first if available. For the cells / beams with no available LI SS / PBCH block RSRP, it may sorted based on LI CSI-RS RSRP measurement results.

[0111] Cell level LI measurement for the last serving cell may be logged in the RLF report if available. If there are no cell level LI measurements available, then in one example, the highest beam level LI measurement is chosen as the cell level measurement result. In another example, all the beam level LI measurements are averaged to set the cell level measurement result or any other suitable mathematical calculation with the beam level LI measurement is performed to set the cell level measurement result. In yet another example, the UE may not the log the cell level LI measurement result.LI measurement results for the neighboring LTM candidate cells

[0112] The LI measurement results can be introduced in the same cell list as the legacy L3measurement results reporting, e.g. measResultListNR in RLF-Report. Different options for this implementation are listed below:• Include LI measurement results within the same list as for L3 measurement results if this LTM candidate cell has available LI and L3 measurement results.• Include LI measurement results within the same list as for L3 measurement results if this LTM candidate cell has available LI and L3 measurement results or if this LTM candidate cell has only available LI measurement results.

[0113] To sort the neighboring cells within measResultListNR, different options are listed below:• Option 1 is that the cell with the highest L3 measurement result (e.g. cell RSRP) is listed first and together with this the UE also includes the LI measurement quantities for the same cell if available. After the measurement results for the cell with the highest L3 measurement result (e.g. cell RSRP) follow measurement results (both L3 measurement results and LI measurement results if available) for the cell with the second highest L3 measurement result (e.g. cell RSRP), and so on until the last L3 measurement result that can be included in the list (which depends on the size of the list). In one method, after the measurement results for the cell with the lowest L3 measurement result follow the LI measurement results for cells for which only LI measurement results are available (i.e. no L3 measurement results are available). In another method, the additional LI measurement results after the last L3 measurement results are included only if there are entries left in the list. These additional LI measurement results may be ordered with the cell with the highest beam level LI measurement result first. Alternatively, it may be up to UE implementation whether the cells with only LI measurements are ordered with the cells with the highest beam level LI measurement results listed first or with the cells with the highest average beam level LI measurement results listed first. o According to this embodiment, since the cells are ordered according to the L3 measurement results, it is the gNB that, based on the LI measurements results included for the cells, deduces the order of the cells based on the LI measurements. In some cases, the order of the cells based on the LI measurement results is the same as the order of the cells based on the L3 measurement results, in another case it is not.• Option 2 is that the cells with the highest beam level LI measurement result or the cells with the highest average beam level LI measurement is listed first, and together with this, the UE also includes the L3 measurement quantities for the same cell if available. After the measurement results for the cell with the highest LI measurement result (e.g. highest beam level RSRP, or highest average beam level RSRP) follow measurement results (both LI measurement results and L3 measurement results if available) for the cell with the second highest LI measurement result (e.g. highest beam level RSRP, or highest average beam level RSRP), and so on until the last LI measurement result that can be included in the list (which depends on the size of the list). In one method, after the measurement results for the cell with the lowest LI measurement result follow cells for which only L3 measurement results are available (i.e. no LI measurement results are available). In another method, the additional L3 measurement results after the last LI measurement results are included only if there are entries left in the list. These additional L3 measurement results may be ordered with the cell with the highest cell level L3 measurement result first.• Option 3 is that under certain conditions, the sorting based on option 1 is used, and under some other conditions, the sorting based on option 2 is used. One implementation example for the conditions when the SON report is an RLF report is that if the RLF- Report is due to an LTM cell switch failure, then sorting based on option 1, otherwise option 2.

[0114] Alternatively, a separate cell list may be introduced in RLF-Report to report the LI measurement results e.g. a new measurement cell list other than the legacy measResultListNR in RLF-Report, for example, define a new cell list measResultLINeighCells in RLF-Report. Different options for this implementation are listed below:• Keep the L3 measurement reporting in measResultListNR and report LI measurement results in measResultLINeighCells.• If both LI and L3 measurements available for an LTM candidate cell, then report this cell with LI and L3 measurement results in measResultListNR and if only LI measurements are available for an LTM candidate cell, then report this cell with LI measurements in measResultLINeighCells .

[0115] To sort the neighboring cells within measResultLINeighCells, different options are listed below:• Option 1 is not to sort the neighboring cells, for each measurement frequency, measResultLINeighCells contains all the LTM candidate cells.• Option 2 is that the cells with the highest beam level LI measurement or the cells with the highest average beam level LI measurement is listed first.• Option 3 is that the LI measurement results in measResultLINeighCells are sorted cell by cell in the same order as the L3 measurement results are sorted in measResultListNR. Any additional LI measurement results, i.e. for cells for which there are no L3 measurement results in measResultListNR, may be sorted in accordance with option 1 or option 2 above.

[0116] During LTM, a UE may not be required to measure cell level LI RSRP for neighboring cell. Therefore, in one example, cell level LI measurement for neighboring cell may not be logged in the RLF-Report. In another example, the cell level LI RSRP may be set as the highest beam level LI RSRP measurement result of that cell. In another example, the cell level RSRP may be set to the average of the beam level LI RSRP measurement results of that cell. In some embodiments, the UE may report (following one of the above examples) measurements from neighbor cells regardless of whether the neighbor cells are LTM candidate cells or not. In some other embodiments, the UE may report (following one of the above examples) measurements only from neighbor cells that are LTM candidate cells.

[0117] In some embodiments, for each LTM candidate cell with available LI measurement results, the beam level LI measurement results may not need to be sorted if all the available LI measurement results can be reported or if all the beam level LI measurement results that are higher than a threshold can be reported, or if the highest N beam level LI measurement results can be reported. In some of the embodiments, this applies to LI measurement results on beams in neighbor cells which are not LTM candidate cells (i.e. LI measurement results on beams in non-LTM candidate neighbor cells may also be reported).

[0118] In some other embodiments, for each LTM candidate cell with available LI measurement results, the beam level LI measurement results may be ordered such that the beam with the highest LI measurements is listed first no matter if there is any restriction on the number or on the value(s) of the reported beam level LI measurement results. In some of the embodiments, this applies to LI measurement results on beams in neighbor cells which are not LTM candidate cells (i.e. LI measurement results on beams in non-LTM candidate neighbor cells may also be reported).

[0119] In some embodiments, where the number of neighbor cells, or (in some variants) thenumber of beams, for which LI measurement results may be reported is limited to a configured or specified number, e.g. N, then, if there are LI measurement results available for more than N neighbor cells (or more than N beams), the UE may prioritize reporting the LI measurement results from neighbor cells that are LTM candidate cells. For instance, if there are LI measurement results available for N+5 neighbor cells, and N+l of these neighbor cells are LTM candidate cells, the UE may report the LI measurement results from N of the N+l LTM candidate cells (selected and sorted according to any of the previously described sorting methods), even if there are LI measurement results available for non-LTM candidate neighbor cells which are better than one or more of the LI measurement results selected to be reported (i.e. even if there are LI measurement results available for non-LTM candidate neighbor cells which, according to the applied sorting method, would place them earlier in the list of reported LI measurement results if the UE had ignored the neighbor cell’s LTM candidate / non-LTM candidate status in the sorting of the measurement results to be reported).LI measurement result, Ll-RSRP value and differential Ll-RSRP

[0120] The LI measured Ll-RSRP value can be mapped to the reported value in RLF report based on some predefined mapping table, e.g. Table 10.1.6.1-1 in 3GPP TS 38.133 version 18.6.0. The reporting range for the Ll-RSRP measurement in the RLF report can follow the range of Ll-RSRP for LI measurement reporting (i.e. CSI reporting) or may follow the range of L3 RSRP for L3 measurement reporting.

[0121] Alternatively, the LI measured Ll-RSRP logged in the RLF report can be in the form of one reported full RSRP value followed by differential RSRP values based on some predefined mapping table, e.g. Table 10.1.6.1-2 in 3GPP TS 38.133 version 18.6.0. With differential LI measurement results reporting, the RLF report signaling overhead can be relatively low.

[0122] If in a later release of the 3GPP standard (e.g. release 20+), more LI measurement quantities are supported, e.g. Ll-RSRQ, Ll-SINR, etc. then in the RLF-Report, the value of Ll-RSRQ and / or Ll-SINR may be reported. Similarly in another implementation example, the differential Ll-RSRQ and / or Ll-SINR may be reported in RLF-Report. That is, any of the previously described embodiments, methods, options and examples may be applied also for measurement and reporting (in an RLF report or another SON report) of other LI measurement quantities than Ll-RSRP, such as Ll-RSRQ or Ll-SINR.Logging LTM cell indicationsIndication of whether last serving cell is LTM candidate cell or not (i.e., the first indication discussed in relation to Figures 4 and 5)

[0123] If the LI measurements for the last serving cell are logged no matter if the serving cell is configured as a LTM candidate cell or what the configuration of spCelllnclusion is, an explicit indication can be used to indicate if the last serving cell is an LTM candidate cell or not. This indication can (as one option) be used no matter if there are logged LI measurement results for the last serving cell, or (as another option) it can be used only when there are logged LI measurement results for the last serving cell, or (as yet another option) it can be used only when there are no logged LI measurement results for the last serving cell. The last serving cell may refer to a source PCell (in case of HO failure or LTM cell switch failure) or a PCell (in case of RLF).

[0124] If the LI measurements for the last serving cell are logged only when it is configured as an LTM candidate cell and spCelllnclusion is set, the inclusion of LI measurement can implicitly indicate, e.g. in the RLF report, that the last serving cell is an LTM candidate cell. Alternatively, an explicit indication can be used to indicate if the last serving cell is an LTM candidate cell or not. This indication can be used no matter if there is logged LI measurement results, or it can be used only when there are no logged LI measurement results. As another option, the explicit indication may be used only if there are no logged LI measurement results for the last serving cell, whereas if there are logged LI measurement results for the last serving cell (and if such LI measurement results are logged for the last serving cell only if the last serving cell is an LTM candidate cell), the presence of LI measurement results for the last serving cell in the SON report (e.g. the RLF report) may implicitly indicate that the last serving cell is an LTM candidate cell. Note that in options / variants where an explicit indication is used in a SON report (e.g. the RLF report) to indicate whether the last serving cell is an LTM candidate cell, this may have the form of a BOOLEAN Abstract Syntax Notation One (ASN. 1) type indication (with the possible values being “true” and “false”) or an ENUMERATED ASN. l type indicator (with a single possible value, e.g. “true”), where in the latter case the ENUMERATED type indicator would be optional and absence of it would indicate that the last serving cell is not an LTM candidate cell (or vice versa).

[0125] The last serving cell may be a source PCell (in case of HO failure or LTM cell switch failure), a source PSCell (in case of PSCell Addition failure, PSCell Cange failure or LTM foradding or changing a PSCell), or a PCell (in case of RLF).Indication of whether a neighboring cell is LTM candidate cell or not (i.e., the second indication discussed in relation to Figures 4 and 5)

[0126] If there are L 1 measurement results reported for a neighboring cell in the RLF report, the Network (NW) can understand that this cell is an LTM candidate cell, provided that (according to standard specification or configuration) LI measurement results are not reported for non-LTM candidate neighbor cells. However, there may still be no available LI measurement even for a LTM candidate cell. Thus, the presence of LI measurements for a neighbor cell can be seen as an implicit indication that it is an LTM candidate cell. Therefore, an explicit indication of whether a neighbor cell is an LTM candidate cell or not may not be needed. On the other hand, in this embodiment, the absence of LI measurements for a neighbor cell is not used to conclude that the cell is not an LTM candidate cell.

[0127] An explicit indication of whether a neighbor cell is an LTM candidate cell or not can be logged no matter if there is LI measurements reported. Or, as an alternative which may be combined with any of the above examples, this explicit indication may only be logged when there are no LI measurements reported, and the presence of LI measurement reports can be seen as implicit indication that the cell is an LTM candidate cell. One implementation example is to introduce the explicit indication within MeasResultsNR or any other new MeasResults Information Element (IE) (or other new IE) designed for LTM LI measurement reports in the RLF-Report, where the explicit indication e.g. could be denoted as ItmCandidate, which is set to “true” when the neighboring cell is an LTM candidate cell, or, when there is no reported LI measurements for an LTM candidate neighbor cell.

[0128] Whether a neighboring cell is an LTM candidate cell or not can also be indicated by a separate list, which is a list of LTM candidate cells at the time of connection failure.• In one example, the list contains the cell indication (i.e. the indication of whether the neighbor cell is an LTM candidate cell) for all the LTM candidate neighbor cells no matter if the cell has LI measurement results logged in the RLF Report or not.• In another example, this list only includes explicit indications for the LTM candidate neighbor cells without LI measurement results logged in the RLF Report.• In another example, this list only contains explicit indications for the LTM candidate neighbor cells without LI and L3 measurement results logged in RLF Report.• In another example (which may be combined with any of the above examples), except the neighboring LTM candidate cells, this list also includes an explicit indication for the last serving cell if it is an LTM candidate cell.Logging access type, whether RACH-based or RACH-less LTMIndication of access type (i. e. , the third indication discussed in relation to Figures 4 and 5) and conditions for this indication

[0129] In case of LTM cell switch failure, if ra-InformationCommon is included in the RLF- Report, the gNB can deduce that it is a RACH-based LTM cell switch failure. Thus, the presence of ra-InformationCommon in the RLF-Report can implicitly indicate if an LTM cell switch failure happens with a RACH-based or RACH-less LTM cell switch. However, in case the failure occurs after the successful execution of the LTM switch, no RA information may be included in the RLF-Report, hence the network may not be able to deduce whether RACH was used for connecting to the cell in which the failure occurred.

[0130] In accordance with the embodiments disclosed herein, an explicit access type indication (i.e. an indication if RACH-less or RACH-based access) may be introduced and a UE may include it in an RLF-Report, in case of radio link failure that happens shortly after a successful LTM cell switch, to indicate if the previous successfully executed LTM was RACH- less or RACH-based.

[0131] In one example, the explicit access type indication (e.g., RACH-less or RACH- based) may be logged in the RLF-Report only in case of radio link failure that happens after a successful LTM cell switch.

[0132] In another example, the explicit access type indication may be logged both in case of a LTM cell switch failure and in case of a radio link failure which happens after a successful LTM cell switch.Explicit indication of access type

[0133] The lastHO-Type in RLF-Report can be extended to indicate if it is RACH-less or RACH-based LTM, e.g. extend to lastHO-Type-r!7 ENUMERATED {cho, daps, rachLessLTM, rachBasedLTM}. Alternatively, lastHO-Type may only extended to indicate LTM cell switch, and a new IE may be introduced to indicate the access type. For example, lastHO-Type-r!7 may be extended to {cho, daps, Itm, sparel}, and anew IE may be introduced to indicate the access type, e.g. an ENUMERATED ASN.l type IE lastAccedssType-Type withthe possible values {rachLess, rachBased} , or a new ENUMERATED ASN. 1 type IE mazy be denoted as rachLessAccess with the only possible value being {true} (while absence of the IE indicates RACH-based access), or a new BOOLEAN ASN. l type IE, e.g. may be denoted as rachLessAccess with possible values being “true” and “false”.

[0134] In one example, the explicit access type indication may be used to differentiate RACH-less LTM and RACH-based LTM. In another example, this explicit access type indication may be used to differentiate RACH-less LTM and RACH-based LTM and to differentiate RACH-less L3 handover and RACH-based L3 handover (note that these handover types may also be subject to MRO mechanisms, e.g. involving reporting of related information in SON reports, e.g. the RLF report).Indication of access type in SHR

[0135] When SHR is triggered due to T304 cause (i.e. timer T304 passes a configured percentage of the configured T304 value / duration), the RACH related information associated to the random-access procedure in the target PCell is logged in SHR. Thus, in case that LTM SHR is triggered due to T304 cause, the presence of ra-InformationCommon can implicitly indicate that it is a RACH-based LTM cell switch (or RACH-based HO), and the absence of ra-InformationCommon can implicitly indicate that it is a RACH-less LTM.

[0136] However, if the SHR is triggered due to reasons other than T304 cause, according to 3GPP TS 38.331 version 18.3.0, no RACH related information associated to the random access procedure in the target PCell may be logged in SHR. In this case, an explicit access type indication may be introduced to indicate if the successfully executed LTM was RACH-less or RACH-based.

[0137] One option is that the explicit access type indication may be used to indicate RACH- less or RACH-based LTM if SHR is triggered due to reasons other than T304 cause. Alternatively, this explicit access type indication may be logged in SHR triggered due to any reason.

[0138] Another option is that the condition to log RACH related information associated to the random access procedure in the target PCell, e.g. ra-InformationCommon in SHR, may be modified if the SHR is regarding to an LTM cell switch. One example of such a modification of the logging condition is that ra-InformationCommon is logged if there is RACH related information associated to the random access procedure in the target PCell for RACH-based LTM.Logging location information when TA is estimated

[0139] The UE may need to have available TA information before RACH-less LTM. The UE may obtain the TA information using UE-based TA measurement, if configured, and / or by transmitting a preamble towards the candidate cell, if triggered by the gNB.

[0140] In one embodiment, to report the TA information in the SON report, the location information of when this TA is estimated can be sent also in the SON report.

[0141] With UE based TA estimation, the UE may log the location information of when this TA is estimated. With PDCCH ordered TA estimation, the UE may log the location information of when the latest PRACH is transmitted upon PDCCH ordered.Example implementation on the above embodiments

[0142] An example implementation of the above embodiments is given below (TS 38.331 V18.3.0 is taken as the baseline, and new text is indicated by underlined font).5.3.10.5 RLF report content determinationThe UE shall determine the content in the VarRLF-Report as follows:1> clear the information included in VarRLF-Report , if any; l>if the UE is not in SNPN access mode, set the plmn-IdentityList to include the list of EPLMNs stored by the UE (i.e. including the RPLMN); l>else if the UE is in SNPN access mode, set the snpn-IdentityList to include the list of equivalent SNPNs stored by the UE (i.e., including the registered SNPN identity); l>set the measResultLastServCell to include the cell level RSRP, RSRQ and the available SINR, of the source PCell (in case HO failure) or PCell (in case RLF) based on the available SSB and CSI-RS measurements collected up to the moment the UE detected failure; l>if measRSSI-ReportConflg is configured for the measObject indicated as the servingCellMO of the source PCell (in case HO failure) or PCell (in case of RLF), set the measResultLastServCellRSSI to the linear average of the available RS SI sample value(s) provided by lower layers for the frequency of the source PCell (in case HO failure) or PCell (in case of RLF) up to the moment the UE detected the failure;1> if the SS / PBCH block-based measurement quantities are available:2>set the rsIndexResults in measResultLastServCell to include all the available measurement quantities of the source PCell (in case HO failure) or PCell (in case RLF), ordered such that the highest SS / PBCH block RSRP is listed first if SS / PBCH block RSRP measurement results are available, otherwise the highest SS / PBCH block RSRQ is listed first if SS / PBCH block RSRQ measurement results are available, otherwise the highest SS / PBCH block SINR is listed first, based on the available SS / PBCH block based measurements collected up to the moment the UE detected failure;1> if the CSI-RS based measurement quantities are available:2> set the rsIndexResults in measResultLastServCell to include all the available measurement quantities of the source PCell (in case HO failure) or PCell (in case RLF), ordered such that the highest CSI-RS RSRP is listed first if CSI-RS RSRP measurement results are available, otherwise the highest CSI-RS RSRQ is listed first if CSI-RS RSRQ measurement results are available, otherwise the highest CSI-RS SINR is listed first, based on the available CSI-RS based measurements collected up to the moment the UE detected failure;1 > if the UE supports RLF-Report for LTM and the LI SS / PBCH block-based measurement quantities are available:2>set the rsIndexResultsLl in measResultLILastServCell to include all the available measurement quantities of the source PCell (in case HO failure) or PCell (in case RLF). ordered such that the highest LI SS / PBCH block RSRP is listed first, based on the available LI SS / PBCH block based measurements collected up to the moment the UE detected failure; l>if the UE supports RLF-Report for LTM and the LI CSI-RS based measurement quantities are available:2>set the rsIndexResultsLl in measResultLILastServCell to include all the available measurement quantities of the source PCell (in case HO failure) or PCell (in case RLF), ), ordered such that the highest LI CSI-RS RSRP is listed first, based on theavailable LI CSI-RS based measurements collected up to the moment the UE detected failure; l>for each of the configured measObjectNR in which measurements are available2> if the SS / PBCH block-based measurement quantities are available:3>set the measResultListNR in measResultNeighCells to include all the available measurement quantities of the best measured cells, other than the source PCell (in case HO failure) or PCell (in case RLF), ordered such that the cell with highest SS / PBCH block RSRP is listed first if SS / PBCH block RSRP measurement results are available, otherwise the cell with highest SS / PBCH block RSRQ is listed first if SS / PBCH block RSRQ measurement results are available, otherwise the cell with highest SS / PBCH block SINR is listed first, based on the available SS / PBCH block based measurements collected up to the moment the UE detected failure;4>for each neighbour cell included, include the optional fields that are available;NOTE Oa: For the neighboring cells included in measResultListNR in measResultNeighCells ordered based on the SS / PBCH block measurement quantities, UE also includes the CSI-RS based measurement quantities, if available.2> if the CSI-RS based measurement quantities are available:3>set the measResultListNR in measResultNeighCells to include all the available measurement quantities of the best measured cells, other than the source PCell (in case HO failure) or PCell (in case RLF), ordered such that the cell with highest CSI-RS RSRP is listed first if CSI-RS RSRP measurement results are available, otherwise the cell with highest CSI-RS RSRQ is listed first if CSI-RS RSRQ measurement results are available, otherwise the cell with highest CSI-RS SINR is listed first, based on the available CSI-RS based measurements collected up to the moment the UE detected radio link failure;4>for each neighbour cell included, include the optional fields that are available;NOTE Ob: For ordering the neighboring cells based on the CSI-RS measurement quantities, UE includes measurements only for the cells not yet included in measResultListNR in measResultNeighCells to avoid overriding SS / PBCH blockbased ordered measurements.2>for each neighbour cell, if any, included in measResultListNR in measResultNeighCells :3>if the UE supports RLF-Report for conditional handover and if the neighbour cell is one of the candidate cells for which the reconflgurationWithSync is included in the masterCellGroup in the MCG VarConditionalReconflg at the moment of the detected failure:4>set choConfig in MeasResult2NR to the execution condition for each measld within condTriggerConfig associated to the neighbour cell within the MCG Var Condi ti onalReconfig,'4> if the first entry of choConfig corresponds to a fulfilled execution condition at the moment of handover failure, or radio link failure; or4>if the second entry of choConfig, if available, corresponds to a fulfilled execution condition at the moment of handover failure, or radio link failure:5>set JirstTriggeredEvent to the execution condition condFirstEvent corresponding to the first entry of choConfig or to the execution condition condSecondEvent corresponding to the second entry of choConfig, whichever execution condition was fulfilled first in time;5>set timeBetweenEvents to the elapsed time between the point in time of fulfilling the condition in choConfig that was fulfilled first in time, and the point in time of fulfilling the condition in choConfig that was fulfilled second in time, if both the first execution condition corresponding to the first entry and the second execution condition corresponding to the second entry in the choConfig were fulfilled;3>if the UE supports RLF-Report for LTM and if the neighbour cell is one of the LTM candidate cells and if there is no available LI measurement quantities based on SS / PBCH block or CSI-RS:4>set ItmCandidate m Meas Result NR to true;1> if the UE supports RLF-Report for LTM. for each of the configured LTM candidate cell other than the source PCell (in case HO failure) or PCell (in case RLF) for which LI measurements are available:2> if the LI SS / PBCH block-based measurement quantities are available:3>set the meets ResidLltListNR in measResultLINeighCells to include all the available measurement quantities of the best measured cells, ordered such that the cell with the highest of the best beam level SS / PBCH block RSRP is listed first if SS / PBCH block RSRP measurement results are available, based on the available SS / PBCH block based measurements collected up to the moment the UE detected failure;NOTE Oc: For the neighboring cells included in measResultLIListNR in measResultLlNeishCells ordered based on the SS / PBCH block measurement quantities. UE also includes the CSI-RS based measurement quantities, if available.2> if theLl CSI-RS based measurement quantities are available:3>set the measResultLIListNR in measResultLlNeishCells to include all the available measurement quantities of the best measured cells, ordered such that the cell with the highest of the best beam level CSI-RS RSRP is listed first if CSI-RS RSRP measurement results are available, based on the available CSI-RS based measurements collected up to the moment the UE detected radio link failure;NOTE Od: For ordering the neighboring cells based on the CSI-RS measurement quantities. UE includes measurements only for the cells not vet included in measResultLIListNR in measResultLlNeishCells to avoid overriding SS / PBCH block-based ordered measurements. l>for each of the configured measObjectNR associated with neighboring cells if the associated reportConflgNR includes measRSSI-ReportConflg'.2> set the measResultNeighFreqRSSI in the measResultNeighFreqListRSSI to the linear average of the available RS SI sample value(s) provided by lower layers for the frequencies other than the frequency of the source PCell (in case HO failure) or of the PCell (in case RLF), up to the moment the UE detected failure; l>for each of the configured EUTRA frequencies in which measurements are available;2>set the measResultListEUTRA in measResultNeighCells to include the best measured cells ordered such that the cell with highest RSRP is listed first if RSRP measurement results are available, otherwise the cell with highest RSRQ is listed first, and based on measurements collected up to the moment the UE detected failure;3>for each neighbour cell included, include the optional fields that are available;NOTE 1: The measured quantities are filtered by the L3 filter as configured in the mobility measurement configuration. The measurements are based on the time domain measurement resource restriction, if configured. Exclude-listed cells are not required to be reported. l>set the c-RNTI to the C-RNTI used in the source PCell (in case HO failure) or PCell (in case RLF);1> if the failure is detected due to reconfiguration with sync failure as described in 5.3.5.8.3, set the fields in VarRLF-report as follows:2>set the connectionFaihireType to hof;2>if the UE supports RLF-Report for DAPS handover and if any DAPS bearer was configured while T304 was running:3>set lastHO-Type to daps,'3>if radio link failure was detected in the source PCell, according to clause 5.3.10.3:4>set timeConnSourceDAPS-Failure to the time between the initiation of the DAPS handover execution and the radio link failure detected in the source PCell while T304 was running;4>set the rlf-Cause to the trigger for detecting the source radio link failure in accordance with clause 5.3.10.4;> if the UE supports RLF-Report for conditional handover and if configuration of the conditional handover is available in the MCG VarConditionalReconflg at the moment of the handover failure:3>if the UE executed a conditional handover toward target PCell according to the condRRCReconflg of the target PCell:4>set timeSinceCHO-Reconflg to the time elapsed between the execution of the last RRCReconflguration message including reconflgurationWithSync for the target PCell of the failed conditional handover, and the reception in the source PCell of the last conditionalReconflguration including the condRRCReconflg of the target PCell of the failed conditional handover;3>else:4>set timeSinceCHO-Reconflg to the time elapsed between the execution of the last RRCReconflguration message including reconflgurationWithSync for the target PCell of the failed handover, and the reception in the source PCell of the last conditionalReconflguration including the condRRCReconflg,'3>set choCandidateCellList to include the global cell identity, if available, and otherwise to the physical cell identity and carrier frequency of each of the candidate target cells for conditional handover included in condRRCReconflg within the MCG VarConditionalReconflg at the time of the failed handover, excluding the candidate target cells included in measResultNeighCells,' >if the UE supports RLF-Report for conditional handover and if the last executed RRCReconflguration message including reconflgurationWithSync was concerning a conditional handover:3>set lastHO-Type to cho,' > if the UE supports RLF-Report for LTM and if the last executed RRCReconflguration message including reconflgurationWithSync was concerning a LTM cell switch:2>set the nrFailedPCellld in failedPCellld to the global cell identity and tracking area code, if available, and otherwise to the physical cell identity and carrier frequency of the target PCell of the failed handover;2> include nrPreviousCell in previousPCellld and set it to the global cell identity and tracking area code of the PCell where the last RRCReconfiguration message including reconflgurationWithSync was received;2>set the timeConnFailure to the elapsed time since the execution of the last RRCReconfiguration message including the reconflgurationWithSync, l>else if the failure is detected due to Mobility from NR failure as described in 5.4.3.5, set the fields in VarRLF-report as follows:2>set the connectionFaihireType to hofl.2> if last MobilityFromNRCommand concerned a failed inter-RAT handover from NR to E-UTRA and if the UE supports Radio Link Failure Report for Inter-RAT MRO EUTRA (NR to EUTRA):3>set the eutraFailedPCellld in failedPCellld to the global cell identity and tracking area code, if available, and otherwise to the physical cell identity and carrier frequency of the target PCell of the failed handover;2> include nrPreviousCell in previousPCellld and set it to the global cell identity and tracking area code of the PCell where the last MobilityFromNRCommand message was received;2>set the timeConnFailure to the elapsed time since the initialization of the handover associated to the last MobilityFromNRCommand message;2>if the UE supports RLF report for inter-system handover for voice fallback and if voiceFallbacklndication is included in the last MobilityFromNRCommand'.3> include the voice Fa UbackHO; l>else if the failure is detected due to radio link failure as described in 5.3.10.3, set the fields in VarRLF-report as follows:2>set the connectionFaihireType to rlfi,> set the rlf-Cause to the trigger for detecting radio link failure in accordance with clause 5.3.10.4; >set the nrFailedPCellld in failedPCellld to the global cell identity and the tracking area code, if available, and otherwise to the physical cell identity and carrier frequency of the PCell where radio link failure is detected; >if an RRCReconflguration message including the reconflgurationWithSync was received before the connection failure:3>if the last successfully executed RRCReconflguration message including the reconflgurationWithSync concerned an intra NR handover and it was received while connected to the previous PCell to which the UE was connected before connecting to the PCell where radio link failure is detected; and3>if T316 was not running before entering the PCell in which the radio link failure was detected; and3>if T311 was not running before entering the PCell in which the radio link failure was detected:4> include the nrPreviousCell in previousPCellld and set it to the global cell identity and the tracking area code of the PCell where the last executed RRCReconflguration message including reconflgurationWithSync was received;4>if the last executed RRCReconflguration message including reconflgurationWithSync was concerning a DAPS handover:5>set lastHO-Type to daps,'4>else if the last executed RRCReconflguration message including reconflgurationWithSync was concerning a conditional handover:5>set lastHO-Type to cho.'4>else if the last executed RRCReconflguration message including reconflgurationWithSync was concerning a LTM cell switch:5>set lastHO-Type to Itm.'4>set the timeConnFailure to the elapsed time since the execution of the last RRCReconflguration message including the reconflgurationWithSync,3>else if the last RRCReconflguration message including the reconflgurationWithSync concerned a handover to NR from E-UTRA and if the UE supports Radio Link Failure Report for Inter-RAT MRO EUTRA:4> include the eutraPreviousCell in previousPCellld and set it to the global cell identity and the tracking area code of the E-UTRA PCell where the last RRCReconflguration message including reconflgurationWithSync was received embedded in E-UTRA RRC message Mobility FromEUTRACommand message as specified in TS 36.331

[0010] clause 5.4.3.3;4>set the timeConnFailure to the elapsed time since reception of the last RRCReconflguration message including the reconflgurationWithSync embedded in E-UTRA RRC message Mobility FromEUTRACommand message as specified in TS 36.331

[0010] clause 5.4.3.3;3>if the last executed RRCReconflguration message including reconflgurationWithSync was concerning a RACH-less mobility procedure:4>set rachLess to true2>if configuration of the conditional handover is available in the MCG VarConditionalReconfig at the moment of declaring the radio link failure:3>set timeSinceCHO-Reconfig to the time elapsed between the detection of the radio link failure, and the reception, in the source PCell, of the last conditionalReconfiguration including the condRRCReconflg message;3>set choCandidateCellList to include the global cell identity if available, and otherwise to the physical cell identity and carrier frequency of each of all the candidate target cells for conditional handover included in condRRCReconflg within the MCG VarConditionalReconfig at the time of radio link failure, excluding the candidate target cells included in measResultNeighCells,' l>if connectionFailur eType is rlf and the rlf-Cause is set to randomAccessProblem or beamFailureRecoveryFailure,' orl>if connectionFailur eType is rlf and the rlf-Cause is set to IbtFailure and the radio link failure is detected during the random access procedure; or1> if connectionFailur eType is hof and if the failed handover is an intra-RAT handover:2>set the ra-InformationCommon to include the random-access related information as described in clause 5.7.10.5;1> if connectionFailur eType is rlf and the rlf-Cause is set to IbtFailure, and the radio link failure is not detected during the random access procedure:2>set the locationAndBandwidth and subcarrierSpacing in bwp-Info associated to the UL BWP in which the consistent uplink LBT failure was detected;1> if the rlf-Cause is set to t310-Expiry or t312-Expiry.2>set the ssbRLMConflgBitmap and / or csi-rsRLMConflgBitmap in measResultLastServCell to include the radio link monitoring configuration of the last serving cell, if available;1> if available, set the locationinfo as in 5.3.3.7.The UE may discard the radio link failure information or handover failure information, i.e. release the UE variable VarRLF-Report, 48 hours after the radio link failure / handover failure is detected.NOTE 2: In this clause, the term 'handover failure' has been used to refer to'reconfiguration with sync failure'.

[0143] The following is an example of an ASN.l implementation matching the above procedural text.RLF-Report-rl 6 : : = CHOICE { nr-RLF-Report-rl 6 SEQUENCE { measResultLastServCell-rl 6 MeasResultRLFNR-rl 6 , measResultNe ighCells -rl 6 SEQUENCE { measResultListNR-r 16 Meas ResultList2NR- r! 6 OPT IONAL , measResultListEUTRA-r 16 Meas ResultLis t2EUTRA-rl 6 OPTIONAL 1 OPTIONAL, c-RNT I -r! 6 RNTI-Value ,previousPCellId-r!6 CHOICE { nrPreviousCell-r!6 CGI- Inf o-Logging- r!6, eutraPreviousCell-r 16 CGI-Inf oEUTRALogging}OPTIONAL, failedPCellId-r!6 CHOICE { nrFailedPCellId-rl6 CHOICE { cellGlobalId-rl6 CGI-Info-Logging-rl 6, pci-arfcn-r!6 PCI -ARFCN-NR- r!6} , eutraFailedPCellld-rl 6 CHOICE { cellGlobalId-rl6 CGI-Inf oEUTRALogging, pci-arfcn-r!6 PCI-ARFCN-EUTRA-rl 6}}, reconnectCellId-rl6 CHOICE { nrReconnectCellld-r 16 CGI- Inf o-Logging- r!6, eutraReconnectCellld-rl 6 CGI-Inf oEUTRALogging}OPTIONAL, timeUntilReconnection-r 16 TimeUntilReconnection- r!6 OPTIONAL, reestablishmentCellld-r 16 CGI -Info -Logging- rl 6OPTIONAL, timeConnFailure-rl 6 INTEGER (0. .1023)OPTIONAL, times inceFailure-rl 6 Times inceFailure-rl 6, conne c tionFai lure Type -r 16 ENUMERATED {rlf, hof}, rlf-Cause-rl 6 ENUMERATED {t310-Expiry, randomAccess Problem, rlc-MaxNumRetx, beamFailureRecoveryFailure, IbtFailure-r 16, bh- rlf RecoveryFailure , t312-expiry-rl7 , sparel} locationlnfo-rl6 Locationlnfo-rl6OPTIONAL, no Sui t abl e Cell Found- rl 6 ENUMERATED {true}OPTIONAL, ra- In format! onCommon-rl 6 RA-Inf ormationCommon- r!6 OPTIONAL, csi-r sRLMConf igBitmap-vl 650 BIT STRING (SIZE (96) )OPTIONAL lastHO-Type-rl7 ENUMERATED {cho, daps,Itm, sparel} OPTIONAL,timeConnSourceDAPS-Failure-rl 7 TimeConnS our ceDAPS-Failure-rl7 OPTIONAL time Since OHO -Re conf ig-r 17 TimeSinceCHO-Reconf ig- r!7 OPTIONAL, cho0ellld-rl7 CHOICE { cellGlobalId-rl7 CGI- Inf o-Logging- r!6, pci-arfcn-r!7 PCI-ARFCN-NR-r 16 }OPTIONAL, choCandidateCellList-r 17 ChoCandidateCellList- r!7 OPTIONAL pSCellId-r!8 CHOICE { cellGlobalId-rl8 CGI- Inf o-Logging- r!6, pci-arfcn-r!8 PCI-ARFCN-NR-r 16 }OPTIONAL, mcg-RecoveryFailureCause-r 18 ENUMERATED {t316-Expiry, scg-Deactivated, spare2, sparel} OPTIONAL, scg-FailureCause-rl 8 ENUMERATED {t310-Expiry, randomAccess Problem, rlc-MaxNumRetx, synchReconf ig Failure SCG, s eg- Re con fig Failure , srb3- IntegrityFailure, scg-lbtFailure, beamFailureRecoveryFailure , t312-Expiry, bh-RLF, beamFailure, spare5, spare4, spare3, spare2, sparel }OPTIONAL, elaps edTime SCG-Failure-rl 8 E laps edTime SCG- Failure - rl8 OPTIONAL, voiceFallbackHO-r!8 ENUMERATED {true}OPTIONAL, measResultLastServCellRSSI-rl 8 RSSI-Range-rl6OPTIONAL, measResultNeighFreqListRSSI-r!8MeasResultNeighFreqListRSSI-r 18 OPTIONAL, bwp-Info-r!8 AttemptedBWP-Info- rl 8OPTIONAL, elaps edTimeT316-r 18 ElapsedTimeT316-rl8OPTIONAL, scg-FailedAf terMCG-r!8 ENUMERATED {true}OPTIONAL_ rachLess-r!9 _ ENUMERATED {true} _ OPTIONAL,_ measResultLILastServCell-r 19 _ MeasResultLlRLFNR-rl9, OPTIONAL,_ measResultLINeighCells-rl 9 _ MeasResultLlList2NR-eutra-RLF-Report-rl 6 SEQUENCE { failedPCellld-EUTRA CGI-InfoEUTRALogging, measResult-RLF-Report-EUTRA-r!6 OCTET STRING, measResult-RLF-Report-EUTRA-vl 690 OCTET STRINGOPTIONAL} } <omitted>MeasResultList2NR-rl 6 : := SEQUENCE (SIZE ( 1.. maxFreq) ) OFMeasResult2NR-r 16MeasResultList2EUTRA-rl 6 : := SEQUENCE (SIZE ( 1.. maxFreq) ) OFMeasResult2EUTRA-rl6MeasResultLlList2NR-rl9 : := SEQUENCE (SIZE ( 1.. maxFreq) ) OFMeasResultL12NR-r 19MeasResult2NR-rl6 : := SEQUENCE { ssbFrequency-r 16 ARFCN-ValueNROPTIONAL, refFreqCSI-RS-rl 6 ARFCN-ValueNROPTIONAL, measResultList-r!6 MeasResultListNR}MeasResultL12NR-rl9 : := SEQUENCE { ssbFrequency-r 19 ARFCN-ValueNR OPTIONAL, measResultList-rl9 MeasResultLIListNR,>}MeasResultListLogging2NR-rl 6 : := SEQUENCE (SIZE ( 1.. maxFreq) ) OF MeasResultLogging2NR-rl 6MeasResultLogging2NR-rl 6 : := SEQUENCE { carrierFreq-r 16 ARFCN-ValueNR, measResultListLoggingNR-r 16 MeasResultListLoggingNR-rl 6} MeasResultListLoggingNR-rl6 : := SEQUENCE (SIZE( 1. . maxCellReport) ) OF MeasResultLoggingNR-r 16MeasResultLoggingNR-rl6 : := SEQUENCE { physCellld-rl 6 PhysCellld, resultsSSB-Cell-r!6 Me as Quantity Re suits , numberOfGoodSSB-r!6 INTEGER ( 1. . maxNrof SSBs- r!6) OPTIONALMeasResult2EUTRA-rl6 : := SEQUENCE { carrier Freq-rl6 ARFCN-ValueEUTRA, measResultList-r!6 MeasResultListEUTRA}MeasResultRLFNR-rl 6 : := SEQUENCE { measResult-rl 6 SEQUENCE { cellResults-r!6 SEQUENCE! resultsSSB-Cell-r!6 Me as Quant ityRe suitsOPTIONAL, resultsCSI-RS-Cell-rl 6 Me as Quant ityRe suitsOPTIONAL}, rs IndexResults-r 16 SEQUENCE! resultsS SB- Indexes -rl 6 ResultsPerSSB-IndexList OPTIONAL, s sbRLMConf igBitmap-rl 6 BIT STRING (SIZE(64) ) OPTIONAL, r e sul t sCSI -RS- Indexes -r 16 ResultsPerCSI-RS-IndexList OPTIONAL, csi-rsRLMConfigBi tmap - r 16 BIT STRING (SIZEMeasResultSuccessH0NR-rl7 : := SEQUENCE { measResult-rl7 SEQUENCE { cellResults-r!7 SEQUENCE { resultsSSB-Cell-rl7 Me as Quant ityRe suitsOPTIONAL, resultsCSI-RS-Cell-rl7 Me a s Quant ityRe suitsOPTIONAL}, rs IndexResults-r 17 SEQUENCE { resultsS SB- Indexes -r 17 ResultsPerSSB-IndexList OPTIONAL, r e sul t sCSI -RS- Indexes -r 17 ResultsPerCSI-RS-IndexList OPTIONALChoCandidateCellList-rl7 : := SEQUENCE (SIZE( 1. . maxNrof CondCells -rl 6) ) OF ChoCandidateCell-r 17ChoCandidateCell-r 17 : := CHOICE { cellGloballd-r 17 CGI-Info-Logging-rl 6 pci-arfcn-rl7 PCI-ARFCN-NR-rl 6}SHR-Cause-r 17 : := SEQUENCE { t304-cause-rl7 ENUMERATED {true}OPTIONAL, t310-cause-rl7 ENUMERATED {true}OPTIONAL, t312-cause-rl7 ENUMERATED {true}OPTIONAL, sourceDAPS-Failure-rl7 ENUMERATED {true}OPTIONAL,}SPR-Cause-rl8 : : = SEQUENCE { t304-cause-r!8 ENUMERATED {true}OPTIONAL, t310-cause-r!8 ENUMERATED {true}OPTIONAL, t312-cause-r!8 ENUMERATED {true}OPTIONAL,}TimeSinceFailure-r 16 INTEGER (0. . 172800)MobilityHistoryReport-rl 6 : := VisitedCellInfoList-rl6TimeUntilReconnection-r 16 : := INTEGER (0..172800)TimeSinceCHO-Reconfig-rl7 : := INTEGER (0..1023)TimeSinceCPAC-Reconf ig-r!8 : := INTEGER (0.. 1023)TimeConnSourceDAPS-Failure-rl7 : := INTEGER (0..1023)UPInterruptionTimeAtHO-rl7 : := INTEGER (0..1023)ElapsedTimeT316-r 18 : := INTEGER (0..2000)ElapsedTimeSCG-Failure-r 18 : := INTEGER (0..1023)TimeSinceSHR-rl8 INTEGER (0. .172800)— TAG-UEINFORMATIONRESPONSE-STOP— ASN1STOP- MeasResultsMeasResultListNR : := SEQUENCE (SIZE( 1. . maxCellReport) ) OF MeasResultNRMeasResultNR : := SEQUENCE { physCellld PhysCellldOPTIONAL, me as Re suit SEQUENCE { cellResults SEQUENCE { res ultsSSB- CellMea s Quant ityRe suits OPTIONAL, resultsCSI-RS-CellMeas Quant ityRe suitsOPTIONAL}, rs IndexRe suits SEQUENCE { resultsS SB- Indexes ResultsPerSSB-IndexList OPTIONAL, re suit sCSI -RS -Indexes ResultsPerCSI-RS-IndexList OPTIONAL}OPTIONAL}, cgi-Info CGI-InfoNROPTIONAL choCandidate-rl7 ENUMERATED {true}OPTIONAL, choConf ig-r 17 SEQUENCE (SIZE (1..2) )OF CondTriggerConf ig-rl 6 OPTIONAL, triggeredEvent-r 17 SEQUENCE { timeBetweenEvents-rl7 TimeBetweenEvent- r!7OPTIONAL, f IrstTriggeredEvent-r 17 ENUMERATED{ condFirstEvent, condSecondEvent)OPTIONAL}OPTIONAL firstEntering-r!8 ENUMERATED {true}OPTIONAL ltmCandidate-rl9 ENUMERATED {true}OPTIONAL}MeasResultLlLrstNR : := SEQUENCE (SIZE( 1. . maxCellReport) ) OF MeasResultLINRMeasResultLINR : := SEQUENCE { physCellld PhysCellldOPTIONAL, rsIndexRe suits SEQUENCE { re sultsSSB- Indexes Re suits Per S SB-IndexList OPTIONAL, re suit sCSI -RS -Indexes ResultsPerCS I-RS- IndexList OPTIONAL}}MeasQuantityResults : := SEQUENCE { rsrp RSRP-RangeOPTIONAL, rsrq RSRQ-RangeOPTIONAL, sinr SINR-RangeOPTIONAL}ResultsPerSSB-IndexList : := SEQUENCE (SIZE (1. . maxNrof IndexesToReport2 ) ) OF ResultsPerSSB-IndexResultsPerSSB-Index : := SEQUENCE { ssb-Index SSB-Index, ssb-Results MeasQuantityResultsOPTIONAL}ResultsPerCSI-RS-IndexList: := SEQUENCE (SIZE (1. . maxNrof IndexesToReport2 ) ) OF ResultsPerCSI-RS-IndexResultsPerCSI-RS-Index : := SEQUENCE { csi-RS-Index CSI-RS-Index, csi- RS -Re suits MeasQuantityResultsOPTIONAL}

[0144] The following is an alternative implementation example (new text is indicated by underlined font).5.3.10.5 RLF report content determination [clause numbering from 3GPP TS 38.331]The UE shall determine the content in the VarRLF-Report as follows:1> clear the information included in VarRLF-Report , if any; l>if the UE is not in SNPN access mode, set the plmn-IdentityList to include the list of EPLMNs stored by the UE (i.e. including the RPLMN); l>else if the UE is in SNPN access mode, set the snpn-IdentityList to include the list of equivalent SNPNs stored by the UE (i.e., including the registered SNPN identity); l>set the measResultLastServCell to include the cell level RSRP, RSRQ and the available SINR, of the source PCell (in case HO failure) or PCell (in case RLF) based on the available SSB and CSI-RS measurements collected up to the moment the UE detected failure; l>if measRSSI-ReportConflg is configured for the measObject indicated as the servingCellMO of the source PCell (in case HO failure) or PCell (in case of RLF), set the measResultLastServCellRSSI to the linear average of the available RS SI sample value(s) provided by lower layers for the frequency of the source PCell (in case HO failure) or PCell (in case of RLF) up to the moment the UE detected the failure;1> if the SS / PBCH block-based measurement quantities are available:2>set the rsIndexResults in measResultLastServCell to include all the available measurement quantities of the source PCell (in case HO failure) or PCell (in case RLF), ordered such that the highest SS / PBCH block RSRP is listed first if SS / PBCH block RSRP measurement results are available, otherwise the highest SS / PBCH block RSRQ is listed first if SS / PBCH block RSRQ measurement results are available, otherwise the highest SS / PBCH block SINR is listed first, based on the available SS / PBCH block based measurements collected up to the moment the UE detected failure;1> if the CSI-RS based measurement quantities are available:2> set the rsIndexResults in measResultLastServCell to include all the available measurement quantities of the source PCell (in case HO failure) or PCell (in case RLF), ordered such that the highest CSI-RS RSRP is listed first if CSI-RS RSRP measurement results are available, otherwise the highest CSI-RS RSRQ is listed first if CSI-RS RSRQ measurement results are available, otherwise the highest CSI-RSSINR is listed first, based on the available CSI-RS based measurements collected up to the moment the UE detected failure;1 > if the UE supports RLF-Report for LTM and the LI SS / PBCH block-based measurement quantities are available:2>set the rsIndexResultsLl in measResultLILastServCell to include all the available measurement quantities of the source PCell (in case HO failure) or PCell (in case RLF), ordered such that the highest LI SS / PBCH block RSRP is listed first, based on the available LI SS / PBCH block based measurements collected up to the moment the UE detected failure; l>for each of the configured measObjectNR in which measurements are available2> if the SS / PBCH block-based measurement quantities are available:3>set the measResultListNR in measResultNeighCells to include all the available measurement quantities of the best measured cells, other than the source PCell (in case HO failure) or PCell (in case RLF), ordered such that the cell with highest SS / PBCH block RSRP is listed first if SS / PBCH block RSRP measurement results are available, otherwise the cell with highest SS / PBCH block RSRQ is listed first if SS / PBCH block RSRQ measurement results are available, otherwise the cell with highest SS / PBCH block SINR is listed first, based on the available SS / PBCH block based measurements collected up to the moment the UE detected failure;4>for each neighbour cell included, include the optional fields that are available;NOTE Oa: For the neighboring cells included in measResultListNR in measResultNeighCells ordered based on the SS / PBCH block measurement quantities, UE also includes the CSI-RS based measurement quantities, if available.2> if the CSI-RS based measurement quantities are available:3>set the measResultListNR in measResultNeighCells to include all the available measurement quantities of the best measured cells, other than the source PCell (in case HO failure) or PCell (in case RLF), ordered such that the cell with highest CSI-RS RSRP is listed first if CSI-RS RSRP measurement results are available, otherwise the cell with highest CSI-RS RSRQ is listed first if CSI-RS RSRQmeasurement results are available, otherwise the cell with highest CSI-RS SINR is listed first, based on the available CSI-RS based measurements collected up to the moment the UE detected radio link failure;4>for each neighbour cell included, include the optional fields that are available;NOTE Ob: For ordering the neighboring cells based on the CSI-RS measurement quantities, UE includes measurements only for the cells not yet included in measResultListNR in measResultNeighCells to avoid overriding SS / PBCH blockbased ordered measurements.2>for each neighbour cell, if any, included in measResultListNR in measResultNeighCells :3>if the UE supports RLF-Report for conditional handover and if the neighbour cell is one of the candidate cells for which the reconflgurationWithSync is included in the masterCellGroup in the MCG VarConditionalReconflg at the moment of the detected failure:4>set choConfig in MeasResult2NR to the execution condition for each measld within condTriggerConfig associated to the neighbour cell within the MCG Var Condi ti onalReconfig,'4> if the first entry of choConfig corresponds to a fulfilled execution condition at the moment of handover failure, or radio link failure; or4>if the second entry of choConfig, if available, corresponds to a fulfilled execution condition at the moment of handover failure, or radio link failure:5>set JirstTriggeredEvent to the execution condition condFirstEvent corresponding to the first entry of choConfig or to the execution condition condSecondEvent corresponding to the second entry of choConfig, whichever execution condition was fulfilled first in time;5>set timeBetweenEvents to the elapsed time between the point in time of fulfilling the condition in choConfig that was fulfilled first in time, and the point in time of fulfilling the condition in choConfig that was fulfilled second in time, if both the first execution condition corresponding to the first entryand the second execution condition corresponding to the second entry in the choConfig were fulfilled;1> if the UE supports RLF-Report for LTM, for each neighbor cell for which LI measurements are configured:2> if LI SS / PBCH block-based measurement quantities are available:3> if LI SS / PBCH block-based RSRP measurements are available:4> set the measResultList3NR to include all the available LI SS / PBCH block-based RSRP measurement results of the best measured cells, other than the source PCell (in case HO failure) or PCell (in case RLF). ordered such that the cell with highest LI SS / PBCH block-based RSRP (of all LI SS / PBCH block-based RSRP measurement results for the cell) is listed first.2> if the cell is an LTM candidate cell:3> set ItmCandidate in LlMeasPerCellResult,'NOTE Oc: If LI SS / PBCH block-based RSRP measurement results are available for both neighbour cells that area LTM candidate cells and and neighbour cells that are note LTM candidate cells, then the measurement results for the neighbour cells that are LTM candidate cells are included first. l>for each of the configured measObjectNR associated with neighboring cells if the associated reportConflgNR includes measRSSI-ReportConflg'.2> set the measResultNeighFreqRSSI in the measResultNeighFreqListRSSI to the linear average of the available RS SI sample value(s) provided by lower layers for the frequencies other than the frequency of the source PCell (in case HO failure) or of the PCell (in case RLF), up to the moment the UE detected failure; l>for each of the configured EUTRA frequencies in which measurements are available;2>set the measResultListEUTRA in measResultNeighCells to include the best measured cells ordered such that the cell with highest RSRP is listed first if RSRP measurement results are available, otherwise the cell with highest RSRQ is listed first, and based on measurements collected up to the moment the UE detected failure;3>for each neighbour cell included, include the optional fields that are available;NOTE 1: The measured quantities are filtered by the L3 filter as configured in the mobility measurement configuration. The measurements are based on the time domain measurement resource restriction, if configured. Exclude-listed cells are not required to be reported. l>set the c-RNTI to the C-RNTI used in the source PCell (in case HO failure) or PCell (in case RLF);1> if the failure is detected due to reconfiguration with sync failure as described in 5.3.5.8.3, set the fields in VarRLF-report as follows:2>set the connectionFaihireType to hof;2>if the UE supports RLF-Report for DAPS handover and if any DAPS bearer was configured while T304 was running:3>set lastHO-Type to daps,'3>if radio link failure was detected in the source PCell, according to clause 5.3.10.3:4>set timeConnSourceDAPS-Failure to the time between the initiation of the DAPS handover execution and the radio link failure detected in the source PCell while T304 was running;4>set the rlf-Cause to the trigger for detecting the source radio link failure in accordance with clause 5.3.10.4;2> if the UE supports RLF-Report for conditional handover and if configuration of the conditional handover is available in the MCG VarConditionalReconflg at the moment of the handover failure:3>if the UE executed a conditional handover toward target PCell according to the condRRCReconflg of the target PCell:4>set timeSinceCHO-Reconflg to the time elapsed between the execution of the last RRCReconflguration message including reconflgurationWithSync for the target PCell of the failed conditional handover, and the reception in the sourcePCell of the last conditionalReconflguration including the condRRCReconflg of the target PCell of the failed conditional handover;3>else:4>set timeSinceCHO-Reconflg to the time elapsed between the execution of the last RRCReconflguration message including reconflgurationWithSync for the target PCell of the failed handover, and the reception in the source PCell of the last conditionalReconflguration including the condRRCReconflg,'3>set choCandidateCellList to include the global cell identity, if available, and otherwise to the physical cell identity and carrier frequency of each of the candidate target cells for conditional handover included in condRRCReconflg within the MCG VarConditionalReconfig at the time of the failed handover, excluding the candidate target cells included in measResultNeighCells,'2>if the UE supports RLF-Report for conditional handover and if the last executed RRCReconflguration message including reconflgurationWithSync was concerning a conditional handover:3>set lastHO-Type to cho,'2> if the UE supports RLF-Report for LTM and if the last executed RRCReconflguration message including reconflgurationWithSync was concerning a LTM cell switch:2>set the nrFailedPCellld in failedPCellld to the global cell identity and tracking area code, if available, and otherwise to the physical cell identity and carrier frequency of the target PCell of the failed handover;2> include nrPreviousCell in previousPCellld and set it to the global cell identity and tracking area code of the PCell where the last RRCReconflguration message including reconflgurationWithSync was received;2>set the timeConnFailure to the elapsed time since the execution of the last RRCReconflguration message including the reconflgurationWithSync, l>else if the failure is detected due to Mobility from NR failure as described in 5.4.3.5, set the fields in VarRLF-report as follows:2>set the connectionFailureType to hofi.2> if last MobilityFromNRCommand concerned a failed inter-RAT handover from NR to E-UTRA and if the UE supports Radio Link Failure Report for Inter-RAT MRO EUTRA (NR to EUTRA):3>set the eutraFailedPCellld in failedPCellld to the global cell identity and tracking area code, if available, and otherwise to the physical cell identity and carrier frequency of the target PCell of the failed handover;2> include nrPreviousCell in previousPCellld and set it to the global cell identity and tracking area code of the PCell where the last MobilityFromNRCommand message was received;2>set the timeConnFailure to the elapsed time since the initialization of the handover associated to the last MobilityFromNRCommand message;2>if the UE supports RLF report for inter-system handover for voice fallback and if voiceFallbacklndication is included in the last MobilityFromNRCommand'.3> include the voice Fa UbackHO: l>else if the failure is detected due to radio link failure as described in 5.3.10.3, set the fields in VarRLF-report as follows:2>set the connectionFailureType to rlfi2> set the rlf-Cause to the trigger for detecting radio link failure in accordance with clause 5.3.10.4;2>set the nr FailedPCellld in failedPCellld to the global cell identity and the tracking area code, if available, and otherwise to the physical cell identity and carrier frequency of the PCell where radio link failure is detected;2>if an RRCReconfiguration message including the reconfigurationWithSync was received before the connection failure:3>if the last successfully executed RRCReconfiguration message including the reconfigurationWithSync concerned an intra NR handover and it was receivedwhile connected to the previous PCell to which the UE was connected before connecting to the PCell where radio link failure is detected; and >if T316 was not running before entering the PCell in which the radio link failure was detected; and >if T311 was not running before entering the PCell in which the radio link failure was detected:4> include the nrPreviousCell in previousPCellld and set it to the global cell identity and the tracking area code of the PCell where the last executed RRCReconflguration message including reconflgurationWithSync was received;4>if the last executed RRCReconflguration message including reconflgurationWithSync was concerning a DAPS handover:5>set lastHO-Type to daps,'4>else if the last executed RRCReconflguration message including reconflgurationWithSync was concerning a conditional handover:5>set lastHO-Type to cho.'4>else if the last executed RRCReconflguration message including reconfigurationWithSync was concerning a LTM cell switch:5>set lastHO-Type to Itm.'4>set the timeConnFailure to the elapsed time since the execution of the last RRCReconflguration message including the reconflgurationWithSync, >else if the last RRCReconflguration message including the reconflgurationWithSync concerned a handover to NR from E-UTRA and if the UE supports Radio Link Failure Report for Inter-RAT MRO EUTRA:4> include the eutraPreviousCell in previousPCellld and set it to the global cell identity and the tracking area code of the E-UTRA PCell where the last RRCReconflguration message including reconflgurationWithSync was receivedembedded in E-UTRA RRC message Mobility FromEUTRACommand message as specified in TS 36.331

[0010] clause 5.4.3.3;4>set the timeConnFailure to the elapsed time since reception of the last RRCReconflguration message including the reconflgurationWithSync embedded in E-UTRA RRC message Mobility FromEUTRACommand message as specified in TS 36.331

[0010] clause 5.4.3.3;3>if the last executed RRCReconflguration message including reconflgurationWithSync was concerning a RACH-less mobility procedure:4>set rachLess to true2>if configuration of the conditional handover is available in the MCG VarConditionalReconfig at the moment of declaring the radio link failure:3>set timeSinceCHO-Reconfig to the time elapsed between the detection of the radio link failure, and the reception, in the source PCell, of the last conditionalReconfiguration including the condRRCReconflg message;3>set choCandidateCellList to includethe global cell identity if available, and otherwise to the physical cell identity and carrier frequency of each of all the candidate target cells for conditional handover included in condRRCReconflg within the MCG VarConditionalReconfig at the time of radio link failure, excluding the candidate target cells included in measResultNeighCells,' l>if connectionFailur eType is rlf and the rlf-Cause is set to randomAccessProblem or beamFailureRecoveryFailure,' or l>if connectionFailur eType is rlf and the rlf-Cause is set to IbtFailure and the radio link failure is detected during the random access procedure; or1> if connectionFailur eType is hof and if the failed handover is an intra-RAT handover:2>set the ra-InformationCommon to include the random-access related information as described in clause 5.7.10.5;1> if connectionFailur eType is rlf and the rlf-Cause is set to IbtFailure, and the radio link failure is not detected during the random access procedure:2>set the locationAndBandwidth and subcarrierSpacing in bwp-Info associated to the UL BWP in which the consistent uplink LBT failure was detected;1> if the rlf-Cause is set to t310-Expiry or t312-Expiry.2>set the ssbRLMConflgBitmap and / or csi-rsRLMConflgBitmap in measResultLastServCell to include the radio link monitoring configuration of the last serving cell, if available;1> if available, set the locationinfo as in 5.3.3.7.The UE may discard the radio link failure information or handover failure information, i.e. release the UE variable VarRLF-Report, 48 hours after the radio link failure / handover failure is detected.NOTE 2: In this clause, the term 'handover failure' has been used to refer to'reconfiguration with sync failure'.

[0145] The following is an example of an ASN.1 implementation matching the above procedural text.RLF-Report-rl 6 : := CHOICE { nr-RLF-Report-rl 6 SEQUENCE { measResultLastServCell-rl 6 MeasResultRLFNR-rl 6, measResultNeighCells-rl 6 SEQUENCE { measResultListNR-r 16 MeasResultList2NR r!6 OPTIONAL, measResultListEUTRA-r 16 MeasResultList2EUTRA-rl 6 OPTIONAL1 OPTIONAL, c-RNTI-r!6 RNTI-Value, previousPCellId-rl6 CHOICE { nrPreviousCell-r!6 CGI- Inf o-Logging- r!6, eutraPreviousCell-r 16 CGI- Inf oEUTRALogging 1 OPTIONAL, failedPCellId-rl6 CHOICE { nrFailedPCellId-rl6 CHOICE { cellGlobalId-rl6 CGI-Info- Logging-rl 6, pci-arfcn-r!6 PCI -ARFCN-NR- r!61 , eutraFailedPCellld-rl 6 CHOICE {cellGlobal!d-rl6 CGI-Inf oEUTRALogging, pci-arfcn-r!6 PCI-ARFCN-EUTRA-rl 6}}, reconnectCellId-r!6 CHOICE { nrReconnectCellld-r 16 CGI-Info-Logging- r!6, eutraReconnectCellld-rl 6 CGI-Inf oEUTRALogging}OPTIONAL, timeUntilReconnection-r 16 TimeUntilReconnection- r!6 OPTIONAL, reestablishmentCellld-r 16 CGI -Info -Logging- rl 6OPTIONAL, timeConnFailure-rl 6 INTEGER (0. .1023)OPTIONAL, times inceFailure-rl 6 Times inceFailure-rl 6, conne c tionFai lure Type -r 16 ENUMERATED {rlf, hof}, rlf-Cause-rl 6 ENUMERATED {t310-Expiry, randomAccess Problem, rlc-MaxNumRetx, beamFailureRecoveryFailure, IbtFailure-r 16, bh- rlf RecoveryFailure , t312-expiry-rl7 , sparel} locationlnfo-r!6 Locationlnfo-rl6OPTIONAL, no Sui t abl e Cell Found- rl 6 ENUMERATED {true}OPTIONAL, ra- In format! onCommon-rl 6 RA-Inf ormationCommon- r!6 OPTIONAL, csi-r sRLMConf igBitmap-vl 650 BIT STRING (SIZE (96) )OPTIONAL lastHO-Type-rl7 ENUMERATED {cho, daps,Itm, sparel} OPTIONAL, timeConnSourceDAPS-Failure-rl 7 TimeConnS our ceDAPS-Failure-rl7 OPTIONAL, time Since CHO -Re conf ig-r 17 Time Since CHO- Re conf ig- r!7 OPTIONAL, choCellId-r!7 CHOICE { cellGlobalId-rl7 CGI- Inf o-Logging- r!6, pci-arfcn-r!7 PCI-ARFCN-NR-r 16 }OPTIONAL, choCandidateCellList-r 17 ChoCandidateCellList- r!7 OPTIONAL pSCell!d-rl8 CHOICE {cell Glob all d-rl 8 CGI- Inf o-Logging- r!6, pci-ar fcn-r 18 PCI-ARFCN-NR-r 16}OPTIONAL, mcg-RecoveryFailureCause-r 18 ENUMERATED {t316-Expiry, scg-Deactivated, spare2, sparel} OPTIONAL, scg-FailureCause-rl 8 ENUMERATED {t310-Expiry, randomAccess Problem, rlc-MaxNumRetx, synchReconf ig Failure SCG, s eg- Re con fig Failure , srb3-IntegrityFailure, scg-lbtFailure, beamFailureRecoveryFailure , t312-Expiry, bh-RLF, beamFailure, spare5, spare4, spare3, spare2, sparel }OPTIONAL, elapsedTimeSCG-Failure-rl 8 ElapsedTimeSCG- Failure rl8 OPTIONAL, voiceFallbackH0-r!8 ENUMERATED {true}OPTIONAL, measResultLastServCellRSSI- 18 RSSI-Range-rl6OPTIONAL, measResultNeighFreqListRSSI rl8MeasResultNeighFreqListRSSI-r 18 OPTIONAL, bwp-Info-r!8 AttemptedBWP-Info- rl 8OPTIONAL, elaps edTimeT316-r 18 ElapsedTimeT316-rl8OPTIONAL, scg-FailedAf terMCG-r!8 ENUMERATED {true}OPTIONAL_ rachLess-r!9 _ ENUMERATED {true}OPTIONAL,_ measResultLILastServCell-r 19 _ MeasResultLlRLFNR-rl9,OPTIONAL,_ measResultList3NR-r!9 _ MeasResultList3NR-r 19OPTIONAL b eutra-RLF-Report-rl 6 SEQUENCE { failedPCellld-EUTRA CGI-InfoEUTRALogging, measResult-RLF-Report-EUTRA-r!6 OCTET STRING, measResult-RLF-Report-EUTRA-vl 690 OCTET STRINGOPTIONAL}>MeasResultLIRLFNR-rl 9 : := SEQUENCE { rs!ndexResultsLl-rl9 _ SEQUENCE {_ resultsSSB-Indexes-r!9 _ ResultsPerSSB- IndexListOPTIONAL,},>1MeasResultList3NR-rl 9 : := SEQUENCE (l..maxFreq) OFMeasResult3NR-rl9MeasResult3NR-rl9 : := SEQUENCE {_ ssbFrequency-r 16 _ ARFCN-ValueNROPTIONAL,> UMeasResultList-rl 9 LIMeasResultList-rl 9 ,1LlMeasResultList-rl9 : := SEQUENCE ( 1. . maxLIMeas PerCellResults ) OF LlMeasPerCellResult-rl9LlMeasPerCellResult-rl9 : := SEQUENCE {> pci PhyCellld,> perBeamlndexLIMeasResultList-r 19 SEQUENCE(1. . maxnof PerBeamlndexLIMeasResults ) OF PerBeamlndexLlMeasResult- r!9, ltmCandidate-r!9 ENUMERATED {true} OPTIONAL,1PerBeamIndexLlMeasResult-rl9 : := SEQUENCE {> ssblndex SSB-IndexOPTIONAL,> HRsrp RSRP-RangeOPTIONAL,>}

[0146] Figure 6 shows an example of a communication system 600 in accordance with some embodiments.

[0147] In the example, the communication system 600 includes a telecommunication network 602 that includes an access network 604, such as a radio access network (RAN), and a core network 606, which includes one or more core network nodes 608. The access network 604 includes one or more access network nodes, such as network nodes 610a and 610b (one or more of which may be generally referred to as network nodes 610), or any other similar 3rd Generation Partnership Project (3GPP) access nodes or non-3GPP access points. Moreover, aswill 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 602 includes one or more Open-RAN (ORAN) network nodes. An ORAN network node is a node in the telecommunication network 602 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 602, including one or more network nodes 610 and / or core network nodes 608.

[0148] 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 Al, Fl, Wl, El, 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 610 facilitate direct or indirect connection of user equipment (UE), such as by connecting UEs 612a, 612b, 612c, and 612d (one or more of which may be generally referred to as UEs 612) to the core network 606 over one or more wireless connections.

[0149] 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 600 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 ofdata and / or signals whether via wired or wireless connections. The communication system 600 may include and / or interface with any type of communication, telecommunication, data, cellular, radio network, and / or other similar type of system.

[0150] The UEs 612 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 610 and other communication devices. Similarly, the network nodes 610 are arranged, capable, configured, and / or operable to communicate directly or indirectly with the UEs 612 and / or with other network nodes or equipment in the telecommunication network 602 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 602.

[0151] In the depicted example, the core network 606 connects the network nodes 610 to one or more host computing systems, such as host 616. 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 606 includes one more core network nodes (e.g., core network node 608) 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 608. 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).

[0152] The host 616 may be under the ownership or control of a service provider other than an operator or provider of the access network 604 and / or the telecommunication network 602. The host 616 may host a variety of applications to provide one or more service. Examples of such applications include live and pre-recorded audio / video content, data collection services such as 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.

[0153] As a whole, the communication system 600 of Figure 6 enables connectivity betweenthe 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.

[0154] In some examples, the telecommunication network 602 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunications network 602 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network 602. For example, the telecommunications network 602 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 loT services to yet further UEs.

[0155] In some examples, the UEs 612 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 604 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network 604. 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).

[0156] In the example, the hub 614 communicates with the access network 604 to facilitate indirect communication between one or more UEs (e.g., UE 612c and / or 612d) and network nodes (e.g., network node 610b). In some examples, the hub 614 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub 614 may be a broadband router enabling access to the core network 606 for the UEs. As another example, the hub 614 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 610, or by executable code, script, process, or otherinstructions in the hub 614. As another example, the hub 614 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 614 may be a content source. For example, for a UE that is a VR device, display, loudspeaker, or other media delivery device, the hub 614 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub 614 then provides to the UE either directly, after performing local processing, and / or after adding additional local content. In still another example, the hub 614 acts as a proxy server or orchestrator for the UEs, in particular if one or more of the UEs are low energy loT devices.

[0157] The hub 614 may have a constant / persistent or intermittent connection to the network node 610b. The hub 614 may also allow for a different communication scheme and / or schedule between the hub 614 and UEs (e.g., UE 612c and / or 612d), and between the hub 614 and the core network 606. In other examples, the hub 614 is connected to the core network 606 and / or one or more UEs via a wired connection. Moreover, the hub 614 may be configured to connect to an M2M service provider over the access network 604 and / or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes 610 while still connected via the hub 614 via a wired or wireless connection. In some embodiments, the hub 614 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 610b. In other embodiments, the hub 614 may be a non-dedicated hub - that is, a device which is capable of operating to route communications between the UEs and network node 610b, but which is additionally capable of operating as a communication start and / or end point for certain data channels.

[0158] Figure 7 shows a UE 700 in accordance with some embodiments. The UE 700 presents additional details of some embodiments of the UE 612 of Figure 6. 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 cameras, gaming console or device, music storage / playback device, wearable terminal device, wireless endpoint, mobile station, tablet, laptop, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), an Augmented Reality (AR) or Virtual Reality (VR) 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.

[0159] A UE may support device-to-device (D2D) communication, for example by implementing a 3 GPP 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).

[0160] The UE 700 includes processing circuitry 702 that is operatively coupled via a bus 704 to an input / output interface 706, a power source 708, a memory 710, a communication interface 712, and / or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in Figure 7. 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.

[0161] The processing circuitry 702 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 710. The processing circuitry 702 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 702 may include multiple central processing units (CPUs). The processing circuitry 702 may be configured to cause the UE 702 to perform the methods as described with reference to Figure 4.

[0162] In the example, the input / output interface 706 may be configured to provide an interface or interfaces to an input device, output device, or one or more input and / or outputdevices. 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 700. 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.

[0163] In some embodiments, the power source 708 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 708 may further include power circuitry for delivering power from the power source 708 itself, and / or an external power source, to the various parts of the UE 700 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source 708. Power circuitry may perform any formatting, converting, or other modification to the power from the power source 708 to make the power suitable for the respective components of the UE 700 to which power is supplied.

[0164] The memory 710 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 710 includes one or more application programs 714, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data 716. The memory 710 may store, for use by the UE 700, any of a variety of various operating systems or combinations of operating systems.

[0165] The memory 710 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, holographicdigital 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 710 may allow the UE 700 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 710, which may be or comprise a device-readable storage medium.

[0166] The processing circuitry 702 may be configured to communicate with an access network or other network using the communication interface 712. The communication interface 712 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna 722. The communication interface 712 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 718 and / or a receiver 720 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter 718 and receiver 720 may be coupled to one or more antennas (e.g., antenna 722) and may share circuit components, software or firmware, or alternatively be implemented separately.

[0167] In the illustrated embodiment, communication functions of the communication interface 712 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 / intemet protocol (TCP / IP), synchronous optical networking (SONET), Asynchronous Transfer Mode (ATM), QUIC, Hypertext Transfer Protocol (HTTP),and so forth.

[0168] Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface 712, 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).

[0169] 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 to a robotic arm performing a medical procedure according to the received input.

[0170] A UE, when in the form of an Internet of Things (loT) 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 loT device are a device which is or which is 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 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 loT device comprises circuitry and / or software in dependence of the intended application of the loT device in addition to other components as described in relation to the UE 700 shown in Figure 7.

[0171] As yet another specific example, in an loT scenario, a UE may represent a machine or other device that performs monitoring and / or measurements, and transmits the results ofsuch 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.

[0172] 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.

[0173] Figure 8 shows a network node 800 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).

[0174] 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).

[0175] Other examples of network nodes include multiple transmission point (multi-TRP) 5G access nodes, multi -standard radio (MSR) equipment such as MSR BSs, networkcontrollers 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).

[0176] The network node 800 includes a processing circuitry 802, a memory 804, a communication interface 806, and a power source 808. The network node 800 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 800 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 800 may be configured to support multiple radio access technologies (RATs). In such embodiments, some components may be duplicated (e.g., separate memory 804 for different RATs) and some components may be reused (e.g., a same antenna 810 may be shared by different RATs). The network node 800 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node 800, 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 800.

[0177] The processing circuitry 802 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 800 components, such as the memory 804, to provide network node 800 functionality. For example, the processing circuitry 802 may be configured to cause the network node to perform the methods as described with reference to Figure 5.

[0178] In some embodiments, the processing circuitry 802 includes a system on a chip (SOC). In some embodiments, the processing circuitry 802 includes one or more of radiofrequency (RF) transceiver circuitry 812 and baseband processing circuitry 814. In some embodiments, the radio frequency (RF) transceiver circuitry 812 and the baseband processing circuitry 814 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 812 and baseband processing circuitry 814 may be on the same chip or set of chips, boards, or units.

[0179] The memory 804 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 computerexecutable memory devices that store information, data, and / or instructions that may be used by the processing circuitry 802. The memory 804 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 802 and utilized by the network node 800. The memory 804 may be used to store any calculations made by the processing circuitry 802 and / or any data received via the communication interface 806. In some embodiments, the processing circuitry 802 and memory 804 is integrated.

[0180] The communication interface 806 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 806 comprises port(s) / terminal(s) 816 to send and receive data, for example to and from a network over a wired connection. The communication interface 806 also includes radio front-end circuitry 818 that may be coupled to, or in certain embodiments a part of, the antenna 810. Radio front-end circuitry 818 comprises filters 820 and amplifiers 822. The radio front-end circuitry 818 may be connected to an antenna 810 and processing circuitry 802. The radio front-end circuitry may be configured to condition signals communicated between antenna 810 and processing circuitry 802. The radio front-end circuitry 818 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 818 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters 820 and / or amplifiers 822. The radio signal may then be transmitted via the antenna 810. Similarly, when receiving data, the antenna 810 may collect radio signals which are then converted intodigital data by the radio front-end circuitry 818. The digital data may be passed to the processing circuitry 802. In other embodiments, the communication interface may comprise different components and / or different combinations of components.

[0181] In certain alternative embodiments, the network node 800 does not include separate radio front-end circuitry 818, instead, the processing circuitry 802 includes radio front-end circuitry and is connected to the antenna 810. Similarly, in some embodiments, all or some of the RF transceiver circuitry 812 is part of the communication interface 806. In still other embodiments, the communication interface 806 includes one or more ports or terminals 816, the radio front-end circuitry 818, and the RF transceiver circuitry 812, as part of a radio unit (not shown), and the communication interface 806 communicates with the baseband processing circuitry 814, which is part of a digital unit (not shown).

[0182] The antenna 810 may include one or more antennas, or antenna arrays, configured to send and / or receive wireless signals. The antenna 810 may be coupled to the radio front-end circuitry 818 and may be any type of antenna capable of transmitting and receiving data and / or signals wirelessly. In certain embodiments, the antenna 810 is separate from the network node 800 and connectable to the network node 800 through an interface or port.

[0183] The antenna 810, communication interface 806, and / or the processing circuitry 802 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 810, the communication interface 806, and / or the processing circuitry 802 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.

[0184] The power source 808 provides power to the various components of network node 800 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source 808 may further comprise, or be coupled to, power management circuitry to supply the components of the network node 800 with power for performing the functionality described herein. For example, the network node 800 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 808. As a further example, the power source 808 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.

[0185] Embodiments of the network node 800 may include additional components beyond those shown in Figure 8 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 800 may include user interface equipment to allow input of information into the network node 800 and to allow output of information from the network node 800. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node 800. In some embodiments providing a core network node, such as core network node 108 of FIG. 6, some components, such as the radio front-end circuitry 818 and the RF transceiver circuitry 812 may be omitted.

[0186] Figure 9 is a block diagram illustrating a virtualization environment 900 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 900 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 900 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. Virtualization may facilitate distributed implementations of a network node, UE, core network node, or host.

[0187] Applications 902 (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.

[0188] Hardware 904 includes processing circuitry, memory that stores software and / orinstructions 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 906 (also referred to as hypervisors or virtual machine monitors (VMMs)), provide VMs 908a and 908b (one or more of which may be generally referred to as VMs 908), and / or perform any of the functions, features and / or benefits described in relation with some embodiments described herein. The virtualization layer 906 may present a virtual operating platform that appears like networking hardware to the VMs 908.

[0189] The VMs 908 comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and may be run by a corresponding virtualization layer 906. Different embodiments of the instance of a virtual appliance 902 may be implemented on one or more of VMs 908, 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.

[0190] In the context of NFV, a VM 908 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 908, and that part of hardware 904 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 908 on top of the hardware 904 and corresponds to the application 902.

[0191] Hardware 904 may be implemented in a standalone network node with generic or specific components. Hardware 904 may implement some functions via virtualization. Alternatively, hardware 904 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 910, which, among others, oversees lifecycle management of applications 902. In some embodiments, hardware 904 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. Insome embodiments, some signaling can be provided with the use of a control system 912 which may alternatively be used for communication between hardware nodes and radio units.

[0192] Although the computing devices described herein (e.g., UEs, network nodes) 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.

[0193] 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.

[0194] The following groups of numbered statements set our embodiments of thedisclosure:Group A Embodiments1. A method performed by a user equipment, UE, the method comprising: responsive to detection of radio link failure, RLF, and / or failure or near failure of a mobility procedure, logging, in a data structure, Layer 1, LI, measurement information.2. The method of embodiment 1, wherein the LI measurement information comprises LI measurements obtained by the UE from transmissions by one or more network entities, wherein the one or more network entities comprise at least one neighbor network entity and / or at least one serving network entity of the UE preceding the RLF and / or the failure or near failure of the mobility procedure.3. The method of embodiment 2, wherein the at least one neighbor network entity comprises at least one of a neighbor cell, a neighbor network node, and one or more beams of a neighbor network node, and / or the at least one serving network entity comprises at least one of a serving cell, serving network node, and one or more beams of a serving network node.4. The method of any of embodiments 2-3, wherein the UE obtains the LI measurements by performing at least one LI measurement procedure on the transmission by the one or more network entities.5. The method of any of embodiments 2-4, wherein the LI measurements are logged in the data structure based on whether the at least one neighbor network entity and / or the serving network entity are candidate network entities for the mobility procedure.6. The method of any of embodiments 2-4, wherein the LI measurements are logged in the data structure regardless of whether the at least one neighbor network entity and / or the serving network entity are candidate network entities for the mobility procedure.7. The method of any of embodiments 2-6, wherein the LI measurement information includes L 1 measurements obtained by the UE from transmissions by the serving network entity regardless of whether the serving network entity is configured as a candidatenetwork entity for the mobility procedure and / or whether a configuration for LI measurement reporting requires LI measurement reporting for the serving network entity.8. The method of any of embodiments 2-6, wherein the LI measurement information includes L 1 measurements obtained by the UE from transmissions by the serving network entity based on whether the serving network entity is configured as a candidate network entity for the mobility procedure and / or whether a configuration for LI measurement reporting requires LI measurement reporting for the serving network entity.9. The method of any of embodiments 2-8, wherein the LI measurements include Reference Symbol / Signal Received Power, RSRP, measurements.10. The method of any of embodiments 2-9, wherein the LI measurements include all, or a subset of, a set of LI measurements obtained by the UE in a measurement period.11. The method of embodiment 10, wherein the subset includes one or more LI measurements of the set based on any one or more of: the one or more LI measurements meeting a threshold value; the one or more LI measurements having been obtained for a network entity for which the UE has obtained Layer 3, L3, measurements; the one or more LI measurements having been obtained for a network entity for which the UE has not obtained L3 measurements; the one or more LI measurements having been obtained for a network entity specified by a Radio Resource Control, RRC, configuration for LI measurement reporting; a maximum number of LI measurements and / or L3 measurements allowed to be logged in the data structure; and a maximum number of network entities for which LI measurements and / or L3 measurements are allowed to be logged in the data structure.12. The method of any of embodiments 2-11, wherein logging the LI measurement information comprises ordering the LI measurements in the data structure based on any one or more of:values of the LI measurements; values of L3 measurements obtained by the UE from transmissions by the one or more network entities; and whether the one or more network entities are candidate network entities for the mobility procedure. The method of any of embodiments 2-12, wherein the LI measurements logged in the data structure are based on a mapping of measured values to reported values. The method of any of embodiments 2-13, the method further comprising obtaining the LI measurements. The method of any of the preceding embodiments, wherein the LI measurement information includes: a first indication of whether a serving network entity of the UE preceding the RLF and / or the failure or near failure of the mobility procedure is a candidate network entity for the mobility procedure; and / or a second indication of whether a neighbor network entity of the UE is a candidate network entity for the mobility procedure. The method of embodiment 15, wherein the serving network entity is a serving cell, a serving network node, or a beam of a serving network node, and / or the neighbor network entity is a neighbor cell, a neighbor network node, or a beam of a neighbor network node. The method of any of embodiments 15-16, wherein the first indication is explicit or implicit. The method of embodiment 17, wherein the first indication is explicit if the LI measurement information does not include LI measurements obtained from transmissions by the serving network entity. The method of embodiment 17, wherein the first indication is explicit regardless of whether the LI measurement information includes LI measurements obtained from transmissions by the serving network entity.The method of any of embodiments 17-19, wherein the first indication is implicit if the LI measurement information includes LI measurements obtained by the UE from transmission by the serving network entity. The method of any of embodiments 15-20, wherein the second indication is explicit or implicit. The method of embodiment 21, wherein the second indication is explicit if the LI measurement information does not include LI measurements obtained by the UE from transmissions by the neighbor network entity. The method of embodiment 21, wherein the second indication is explicit regardless of whether the LI measurement information includes LI measurements obtained by the UE from transmissions by the neighbor network entity. The method of any of embodiments 21-23, wherein the second indication is implicit if the LI measurement information includes LI measurements obtained by the UE from transmissions by the neighbor network entity. The method of any preceding embodiment, wherein the LI measurement information includes a third indication of an access type for a serving network entity of the UE preceding the RLF and / or the failure or near failure of the mobility procedure. The method of embodiment 25, wherein the serving network entity is a serving cell, a serving network node, or a beam of a serving network node, and / or the neighbor network entity is a neighbor cell, a neighbor network node, or a beam of a neighbor network node. The method of any of embodiments 25-26, wherein the third indication is included in the LI measurement information following a first network entity switch being successfully performed for the serving network entity. The method of embodiment 27, wherein the first network entity switch is successfully performed before the RLF.29. The method of any of embodiments 25-28, wherein the third indication is explicit or implicit.30. The method of embodiment 29, wherein the third indication is implicit if the LI measurement information is logged in the data structure responsive to T304 expiry and / or the third indication is explicit if the LI measurement information is logged in the data structure responsive to a cause other than T304 expiry.31. The method of embodiment 29, wherein the third indication is explicit regardless of the cause of the LI measurement information being logged in the data structure.32. The method of any of embodiments 25-31, wherein the third indication indicates that the access type for the serving network entity is Random Access Channel, RACH, -less or RACH-based.33. The method of any preceding embodiment, the method further comprising logging, in the data structure, an indication of a location of the UE when the UE performs a procedure for obtaining a Timing Advance, TA, estimation for a RACH-less mobility procedure.34. The method of embodiment 33, wherein the procedure for obtaining the TA estimation comprises initiating a TA measurement procedure or transmitting a preamble towards a candidate network entity for the RACH-less mobility procedure.35. The method of embodiment 34, wherein the candidate network entity is a cell, a network node, or a beam of a network node.36. The method of any preceding embodiment, the method further comprising transmitting, to a network node, a report comprising at least part of the data structure.37. The method of embodiment 36, wherein the report is a Mobility Robustness Optimization, MRO, report or Self Organizing Network, SON, report.38. The method of embodiment 37, wherein the MRO report is an RLF report, a Successful Handover Report, SHR, report, or a Successful Primary Secondary Cell, PSCell, Report, SPR, report.39. The method of any preceding embodiment, wherein the mobility procedure is a Ll / Layer 2, L2, Triggered Mobility, LTM, procedure.Group B Embodiments40. A method performed by a network node, the method comprising: receiving, from a User Equipment, UE, a report comprising a data structure comprising LI measurement information, wherein the LI measurement information is logged in the data structure responsive to a radio link failure, RLF, and / or failure or near failure of a mobility procedure detected by the UE.41. The method of embodiment 40, wherein the LI measurement information comprises LI measurements obtained by the UE from transmissions by one or more network entities, wherein the one or more network entities comprise at least one neighbor network entity and / or at least one serving network entity of the UE preceding the RLF and / or the failure or near failure of the mobility procedure.42. The method of embodiment 41, wherein the at least one neighbor network entity comprises at least one of a neighbor cell, a neighbor network node, and one or more beams of a neighbor network node, and / or the at least one serving network entity comprises at least one of a serving cell, serving network node, and one or more beams of a serving network node.43. The method of any of embodiments 41-42, wherein the LI measurements are included in the LI measurement information based on whether the at least one neighbor network entity and / or the serving network entity are candidate network entities for the mobility procedure.44. The method of any of embodiments 41-42, wherein the LI measurements are included in the LI measurement information regardless of whether the at least one neighbor networkentity and / or the serving network entity are candidate network entities for the mobility procedure.45. The method of any of embodiments 41-44, wherein the LI measurement information includes L 1 measurements obtained by the UE from transmissions by the serving network entity regardless of whether the serving network entity is configured as a candidate network entity for the mobility procedure and / or whether a configuration for LI measurement reporting requires LI measurement reporting for the serving network entity.46. The method of any of embodiments 41-44, wherein the LI measurement information includes L 1 measurements obtained by the UE from transmissions by the serving network entity based on whether the serving network entity is configured as a candidate network entity for the mobility procedure and / or whether a configuration for LI measurement reporting requires LI measurement reporting for the serving network entity.47. The method of any of embodiments 41-46, wherein the LI measurements include Reference Symbol / Signal Received Power, RSRP, measurements.48. The method of any of embodiments 41-47, wherein the LI measurements include all, or a subset of, a set of LI measurements obtained by the UE in a measurement period.49. The method of embodiment 48, wherein the subset includes one or more LI measurements of the set based on any one or more of: the one or more LI measurements meeting a threshold value; the one or more LI measurements having been obtained for a network entity for which the UE has obtained Layer 3, L3, measurements; the one or more LI measurements having been obtained for a network entity for which the UE has not obtained L3 measurements; the one or more LI measurements having been obtained for a network entity specified by a Radio Resource Control, RRC, configuration for LI measurement reporting; a maximum number of LI measurements and / or L3 measurements allowed to be logged in the data structure; anda maximum number of network entities for which LI measurements and / or L3 measurements are allowed to be logged in the data structure. The method of any of embodiments 41-49, wherein logging the LI measurement information comprises ordering the LI measurements in the data structure based on any one or more of: values of the LI measurements; values of L3 measurements obtained by the UE from transmissions by the one or more network entities; and whether the one or more network entities are candidate network entities for the mobility procedure. The method of any of embodiments 41-50, wherein the LI measurements included in the LI measurement information are based on a mapping of measured values to reported values. The method of any of embodiments 40-51, wherein the LI measurement information includes: a first indication of whether a serving network entity of the UE preceding the RLF and / or the failure or near failure of the mobility procedure is a candidate network entity for the mobility procedure; and / or a second indication of whether a neighbor network entity of the UE is a candidate network entity for the mobility procedure. The method of embodiment 52, wherein the serving network entity is a serving cell, a serving network node, or a beam of a serving network node, and / or the neighbor network entity is a neighbor cell, a neighbor network node, or a beam of a neighbor network node. The method of any of embodiments 52-53, wherein the first indication is explicit or implicit. The method of embodiment 54, wherein the first indication is explicit if the LI measurement information does not include LI measurements obtained from transmissions by the serving network entity.The method of embodiment 54, wherein the first indication is explicit regardless of whether the LI measurement information includes LI measurements obtained from transmissions by the serving network entity. The method of any of embodiments 54-56, wherein the first indication is implicit if the LI measurement information includes LI measurements obtained by the UE from transmission by the serving network entity. The method of any of embodiments 52-57, wherein the second indication is explicit or implicit. The method of embodiment 58, wherein the second indication is explicit if the LI measurement information does not include LI measurements obtained by the UE from transmissions by the neighbor network entity. The method of embodiment 58, wherein the second indication is explicit regardless of whether the LI measurement information includes LI measurements obtained by the UE from transmissions by the neighbor network entity. The method of any of embodiments 58-60, wherein the second indication is implicit if the LI measurement information includes LI measurements obtained by the UE from transmissions by the neighbor network entity. The method of any of embodiments 40-61, wherein the LI measurement information includes a third indication of an access type for a serving network entity of the UE preceding the RLF and / or the failure or near failure of the mobility procedure. The method of embodiment 62, wherein the serving network entity is a serving cell, a serving network node, or a beam of a serving network node, and / or the neighbor network entity is a neighbor cell, a neighbor network node, or a beam of a neighbor network node.64. The method of any of embodiments 62-63, wherein the third indication is included in the LI measurement information following a first network entity switch being successfully performed for the serving network entity.65. The method of embodiment 64, wherein the first network entity switch is successfully performed before the RLF.66. The method of any of embodiments 62-65, wherein the third indication is explicit or implicit.67. The method of embodiment 66, wherein the third indication is implicit if the LI measurement information is logged in the data structure responsive to T304 expiry and / or the third indication is explicit if the LI measurement information is logged in the data structure responsive to a cause other than T304 expiry.68. The method of embodiment 66, wherein the third indication is explicit regardless of the cause of the LI measurement information being logged in the data structure.69. The method of any of embodiments 62-68, wherein the third indication indicates that the access type for the serving network entity is Random Access Channel, RACH, -less or RACH-based.70. The method of any of embodiments 40-69, wherein the data structure further comprises an indication of a location of the UE when the UE performs a procedure for obtaining a Timing Advance, TA, estimation for a RACH-less mobility procedure.71. The method of embodiment 70, wherein the procedure comprises performing a TA measurement procedure or transmitting a preamble towards a candidate network entity for the RACH-less mobility procedure.72. The method of embodiment 71 , wherein the candidate network entity is a cell, a network node, or a beam of a network node.13. The method of any of embodiments 40-72, wherein the report is a Mobility Robustness Optimization, MRO, report or Self Organizing Network, SON, report.74. The method of embodiment 73, wherein the MRO report is an RLF report, a Successful Handover Report, SHR, report, or a Successful Primary Secondary Cell, PSCell, Report, SPR, report.75. The method of any of embodiments 40-74, wherein the mobility procedure is a Ll / Layer 2, L2, Triggered Mobility, LTM, procedure.76. The method of any of embodiments 40-75, further comprising determining one or more parameters for handover and / or a configuration of a network based on the LI measurement information.77. The method of any of embodiments 40-76, further comprising sending, to the UE, a request for the report.Group C Embodiments78. 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.79. 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.80. 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 cause the user equipment 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.

Claims

1. CLAIMS1. A method performed by a user equipment, UE (700), the method comprising: responsive to detection of radio link failure, RLF, and / or failure of a mobility procedure, logging (402), in a data structure, Layer 1, LI, measurement information, wherein the LI measurement information comprises LI measurements obtained by the UE from transmissions by one or more network entities, wherein the one or more network entities comprise at least one neighbor network entity and / or at least one serving network entity of the UE preceding the RLF and / or the failure of the mobility procedure.

2. The method of claim 1, wherein the at least one neighbor network entity comprises at least one of a neighbor cell, a neighbor network node, and one or more beams of a neighbor network node, and / or the at least one serving network entity comprises at least one of a serving cell, serving network node, and one or more beams of a serving network node.

3. The method of any of the preceding claims, wherein the UE obtains the LI measurements by performing at least one LI measurement procedure on the transmission by the one or more network entities.

4. The method of any of the preceding claims, wherein the LI measurements are logged in the data structure based on whether the at least one neighbor network entity and / or the serving network entity are candidate network entities for the mobility procedure, or , wherein the LI measurements are logged in the data structure regardless of whether the at least one neighbor network entity and / or the serving network entity are candidate network entities for the mobility procedure.

5. The method of any of the preceding claims, wherein the LI measurement information includes L 1 measurements obtained by the UE from transmissions by the serving network entity regardless of whether the serving network entity is configured as a candidate network entity for the mobility procedure and / or whether a configuration for LI measurement reporting requires LI measurement reporting for the serving network entity, or wherein the LI measurement information includes LI measurements obtained by the UE from transmissions by the serving network entity based on whether the servingnetwork entity is configured as a candidate network entity for the mobility procedure and / or whether a configuration for LI measurement reporting requires LI measurement reporting for the serving network entity.

6. The method of any of the preceding claims, wherein the LI measurements include all, or a subset of, a set of LI measurements obtained by the UE in a measurement period.

7. The method of claim 6, wherein the subset includes one or more LI measurements of the set based on any one or more of: the one or more LI measurements meeting a threshold value; the one or more LI measurements having been obtained for a network entity for which the UE has obtained Layer 3, L3, measurements; the one or more LI measurements having been obtained for a network entity for which the UE has not obtained L3 measurements; the one or more LI measurements having been obtained for a network entity specified by a Radio Resource Control, RRC, configuration for LI measurement reporting; a maximum number of LI measurements and / or L3 measurements allowed to be logged in the data structure; and a maximum number of network entities for which LI measurements and / or L3 measurements are allowed to be logged in the data structure.

8. The method of any of the preceding claims, wherein logging the LI measurement information comprises ordering the LI measurements in the data structure based on any one or more of: values of the LI measurements; values of L3 measurements obtained by the UE from transmissions by the one or more network entities; and whether the one or more network entities are candidate network entities for the mobility procedure.

9. The method of any of the preceding claims, wherein the LI measurement information includes:a first indication of whether a serving network entity of the UE preceding the RLF and / or the failure of the mobility procedure is a candidate network entity for the mobility procedure; and / or a second indication of whether a neighbor network entity of the UE is a candidate network entity for the mobility procedure.

10. The method of claim 9, wherein the serving network entity is a serving cell, a serving network node, or a beam of a serving network node, and / or the neighbor network entity is a neighbor cell, a neighbor network node, or a beam of a neighbor network node.

11. The method of any preceding claim, wherein the LI measurement information includes a third indication of an access type for a serving network entity of the UE preceding the RLF and / or the failure of the mobility procedure.

12. The method of claim 11, wherein the third indication is included in the LI measurement information following a first network entity switch being successfully performed for the serving network entity.

13. The method of claim 12, wherein the first network entity switch is successfully performed before the RLF.

14. The method of any preceding claim, the method further comprising logging, in the data structure, an indication of a location of the UE when the UE performs a procedure for obtaining a Timing Advance, TA, estimation for a RACH-less mobility procedure.

15. The method of any preceding claim, the method further comprising transmitting (404), to a network node (800), a report comprising at least part of the data structure.

16. The method of claim 15, wherein the report is a Mobility Robustness Optimization, MRO, report or Self Organizing Network, SON, report.

17. The method of any preceding claim, wherein the mobility procedure is a Ll / Layer 2, L2, Triggered Mobility, LTM, procedure.

18. A method performed by a network node (800), the method comprising: receiving (502), from a User Equipment, UE (700), a report comprising a data structure comprising LI measurement information, wherein the LI measurement information is logged in the data structure responsive to a radio link failure, RLF, and / or failure of a mobility procedure detected by the UE, wherein the LI measurement information comprises LI measurements obtained by the UE from transmissions by one or more network entities, wherein the one or more network entities comprise at least one neighbor network entity and / or at least one serving network entity of the UE preceding the RLF and / or the failure of the mobility procedure.

19. The method of claim 18, wherein the at least one neighbor network entity comprises at least one of a neighbor cell, a neighbor network node, and one or more beams of a neighbor network node, and / or the at least one serving network entity comprises at least one of a serving cell, serving network node, and one or more beams of a serving network node.

20. The method of any of claims 18-19, wherein the LI measurements are included in the LI measurement information based on whether the at least one neighbor network entity and / or the serving network entity are candidate network entities for the mobility procedure, or, wherein the LI measurements are included in the LI measurement information regardless of whether the at least one neighbor network entity and / or the serving network entity are candidate network entities for the mobility procedure.

21. The method of any of claims 18-20, wherein the LI measurement information includes LI measurements obtained by the UE from transmissions by the serving network entity regardless of whether the serving network entity is configured as a candidate network entity for the mobility procedure and / or whether a configuration for LI measurement reporting requires LI measurement reporting for the serving network entity, or wherein the LI measurement information includes LI measurements obtained by the UE from transmissions by the serving network entity based on whether the serving network entity is configured as a candidate network entity for the mobility procedure and / or whether a configuration for LI measurement reporting requires LI measurement reporting for the serving network entity.

22. The method of any of claims 18-21, wherein the LI measurements include all, or a subset of, a set of LI measurements obtained by the UE in a measurement period.

23. The method of any of claims 18-22, wherein the LI measurements are ordered in the data structure based on any one or more of: values of the LI measurements; values of L3 measurements obtained by the UE from transmissions by the one or more network entities; and whether the one or more network entities are candidate network entities for the mobility procedure.

24. The method of any of claims 18-23, wherein the LI measurement information includes: a first indication of whether a serving network entity of the UE preceding the RLF and / or the failure of the mobility procedure is a candidate network entity for the mobility procedure; and / or a second indication of whether a neighbor network entity of the UE is a candidate network entity for the mobility procedure.

25. The method of any of claims 18-24, wherein the LI measurement information includes a third indication of an access type for a serving network entity of the UE preceding the RLF and / or the failure of the mobility procedure.

26. The method of any of claim 25, wherein the third indication is included in the LI measurement information following a first network entity switch being successfully performed for the serving network entity.

27. The method of claim 26, wherein the first network entity switch is successfully performed before the RLF.

28. The method of any of claims 25-27, wherein the third indication indicates that the access type for the serving network entity is Random Access Channel, RACH, -less or RACH- based.

29. The method of any of claims 18-28, wherein the data structure further comprises an indication of a location of the UE when the UE performs a procedure for obtaining a Timing Advance, TA, estimation for a RACH-less mobility procedure.

30. The method of any of claims 18-29, wherein the report is a Mobility Robustness Optimization, MRO, report or Self Organizing Network, SON, report.

31. The method of claim 30, wherein the MRO report is an RLF report, a Successful Handover Report, SHR, report, or a Successful Primary Secondary Cell, PSCell, Report, SPR, report.

32. The method of any of claims 18-31, wherein the mobility procedure is a Ll / Layer 2, L2, Triggered Mobility, LTM, procedure.

33. The method of any of claims 18-32, further comprising determining (504) one or more parameters for handover and / or a configuration of a network based on the LI measurement information.

34. The method of any of claims 18-33, further comprising sending, to the UE, a request for the report.

35. A user equipment, UE, (700) comprising processing circuitry (702) configured to cause the UE to: responsive to detection of radio link failure, RLF, and / or failure of a mobility procedure, log (402), in a data structure, Layer 1, LI, measurement information, wherein the LI measurement information comprises LI measurements obtained by the UE from transmissions by one or more network entities, wherein the one or more network entities comprise at least one neighbor network entity and / or at least one serving network entity of the UE preceding the RLF and / or the failure of the mobility procedure.

36. The UE of claim 35, wherein the processing circuitry is further configured to cause the UE to perform the method according to any one of claims 2 to 17.

37. A user equipment, UE, (700) adapted to perform the method according to any one of claims 1 to 17.

38. A network node (800) comprising processing circuitry (802) configured to cause the network node to: receive (502), from a User Equipment, UE (700), a report comprising a data structure comprising LI measurement information, wherein the LI measurement information is logged in the data structure responsive to a radio link failure, RLF, and / or failure of a mobility procedure detected by the UE, wherein the LI measurement information comprises LI measurements obtained by the UE from transmissions by one or more network entities, wherein the one or more network entities comprise at least one neighbor network entity and / or at least one serving network entity of the UE preceding the RLF and / or the failure of the mobility procedure.

39. The network node of claim 38, wherein the processing circuitry is further configured to cause the network node to perform the method according to any one of claims 19 to 34.

40. A network node (800) adapted to perform the method according to any one of claims 18 to 34.

41. A computer-readable storage medium storing code which, when executed by processing circuitry (1002) of a user equipment (1000), causes the user equipment to perform a method according to any one of claims 1 to 17.

42. A computer-readable storage medium storing code which, when executed by processing circuitry (802) of a network node (800) of a network node, causes the network node to perform a method according to any one of claims 18 to 34.

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