EP4480213A1 - Two-dimensional mobility history information logging - Google Patents

Abstract

Disclosed is inter alia a user equipment, comprising means for: - connecting the user equipment to a primary network cell; - responsive to the user equipment connecting to the primary network cell: - creating a primary data entry in a nested data structure; - entering cell identity information of the primary network cell in the primary data entry; and - creating a secondary data entry in the nested data structure, wherein the secondary data entry is nested under the primary data entry.

Description

Two-dimensional Mobility History Information Logging

TECHNOLOGICAL FIELD

Various example embodiments according to the present disclosure relate to communication networks, such as wireless radio networks comprising base stations and mobile devices (aka user equipment (UE ] ], communicating with each other. Specifically, various example embodiments according to the present disclosure relate to mobility history information (MHI],

BACKGROUND

Various example embodiments according to the present disclosure are related but not limited to communication networks as defined by the 3GPP standard, such as the 5G standard, also referred to as New Radio [NR],

In wireless communication systems, MHI of a UE may be used for indicating the history of network cells visited by a UE over time. MHI has been introduced to optimize cell change mechanisms based on the history of recently visited cells and may for example be used to detect unnecessary and unwanted successful forth-back handovers (e.g. so-called ping-pong events] or in order to derive UE velocity information. For example, such velocity information may be used for speed-dependent mobility parameter settings or for more sophisticated mobility concepts based on mobility prediction e.g. supported by artificial intelligence [Al] or machine learning [ML] techniques.

For example, MHI may be used when a UE is operating in multi-radio dual-connectivity [MR-DC] mode, where a UE is simultaneously connected to multiple network cells, in particular to a primary network cell (PCell] controlled by a master node [MN] of a master cell group [MCG], and to a primary secondary network cell (PSCell] controlled by a secondary node (SN ] of a secondary cell group [SCG], For example, a UE may operate in dual-connectivity between Long Term Evolution [LTE] and NR, which means that the MN (or the SN] may be an eNodeB (eNB] enabling Evolved Universal Terrestrial Radio Access (E- UTRA], while the SN (or the MN] may be a gNodeB (gNB] enabling NR. This example may be referred to as E-UTRA-NR dual-connectivity (EN-DC] considering that E-UTRA is the MN and NR the SN.

In single-connectivity mode, a UE is connected to a single cell group (i.e., a single cell in case of no carrier aggregation, or a primary cell and related secondary cells for carrier aggregation]. In singleconnectivity mode, a MHI data entry for example would have to log merely the identity of a respective PCell serving a UE and the time the UE spent on this PCell. However, when considering the possibility (e.g. by switching] of both single-connectivity and dual-connectivity operations, logging the history of network cells visited by a UE may become more challenging.

SUMMARY OF SOME EXEMPLARY EMBODIMENTS

Various example embodiments according to the present disclosure may have the effect of providing a framework for logging mobility history information. Specifically, certain exemplary embodiments according to the present disclosure may address logging mobility history information by means of a nested (e.g. two-dimensional] data structure for considering e.g. both single-connectivity and dualconnectivity operation of a UE.

According to an exemplary aspect a user equipment is disclosed, comprising means for: connecting the user equipment to a primary network cell; responsive to the user equipment connecting to the primary network cell: creating a primary data entry in a nested data structure; entering cell identity information of the primary network cell in the primary data entry; and creating a secondary data entry in the nested data structure, wherein the secondary data entry is nested under the primary data entry.

According to the exemplary aspect, a method is also disclosed, the method comprising: connecting a user equipment to a primary network cell; responsive to the user equipment connecting to the primary network cell: creating a primary data entry in a nested data structure; entering cell identity information of the primary network cell in the primary data entry; and creating a secondary data entry in the nested data structure, wherein the secondary data entry is nested under the primary data entry.

This method may for example be performed and/or controlled by an apparatus, for example a UE. For example, the method may be performed and/or controlled by using at least one processor of the UE.

The UE may be understood as stationary device or a mobile device. For example, it may be a UE of a mobile communication network, for instance a 3G, LTE/4G, 5G NR, 5G network, or future communication standards such as e.g. 6G or the like. Further, it may be for example a hand-set, a smartphone, a tablet, a laptop, or any other mobile device. In various embodiments, it may be a vehicle for travelling in air, water, or on land, e.g. a plane or a drone, a ship or a car or a truck. It may also be a robot, a sensor device, a wearable device, an Internet of Things [IoT] device, a Machine Type Communication [MTC] device, or the likes. The means of the UE can be implemented in hardware and/or software. They may comprise for instance at least one processor for executing computer program code for performing the required functions, at least one memory storing the program code, or both. Alternatively, they could comprise for instance circuitry that is designed to implement the required functions, for instance implemented in a chipset or a chip, like an integrated circuit. In general, the means may comprise for instance one or more processing means or processors.

For example, the UE may comprise at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause an apparatus, for example the UE, at least to perform and/or to control the method according to the exemplary aspect.

According to the exemplary aspect, there is also disclosed a computer program, the computer program when executed by a processor of an apparatus, for example a UE, causing said apparatus to perform a method according to the exemplary aspect.

The computer program may be stored on computer-readable storage medium, in particular a tangible and/or non-transitory medium. The computer readable storage medium could for example be a disk or a memory or the like. The computer program could be stored in the computer readable storage medium in the form of instructions encoding the computer-readable storage medium. The computer readable storage medium may be intended for taking part in the operation of a device, like an internal or external memory, for example a Read-Only Memory [ROM] or hard disk of a computer, or be intended for distribution of the program, like an optical disc.

For example, connecting the UE to a primary network cell may occur by the UE leaving IDLE mode while being located within the coverage area of the primary network cell or by entering the primary network cell via handover (e.g. after previously being connected to another primary network cell]. Considering a wireless communication network, a UE may for example be connected to a primary network cell (PCell] provided by a master network node [MN] of a master cell group [MCG], Additionally, the UE may be simultaneously connected to a primary secondary network cell (PSCell] provided by a secondary network node (SN] of a secondary cell group (SCG],

Therein, a network node (e.g. an MN or an SN] may for example be understood as an electronic device, such as a node (e.g. a base station] of the radio access network or the core network of a communication system. For example, the network node may be or comprise such a base station (e.g. a gNodeB/gNB, eNodeB/eNB, BS, access node, access point, or the like] or be in communication with a base station. Generally, a network node may be a hardware and/or software component implementing a certain functionality. In an example of the exemplary aspect, the network node may be a node as defined by the 3GPP 5G standard. Accordingly, while the network node may be understood to be implemented in or be a single device or module, the network node may also be implemented across or comprise multiple devices or modules. Multiple network nodes of the exemplary aspect may in particular establish a communication system or network, which may in particular be an NR or 5G system or any other mobile communications system defined by a past or future standards, in particular successors of the present 3GPP standards.

Responsive to the UE connecting to the primary network cell, the (e.g. three] steps of creating a primary data entry in a nested data structure; entering cell identity information of the primary network cell in the primary data entry; and creating a secondary data entry in the nested data structure, wherein the secondary data entry is nested under the primary data entry, are performed and/or controlled. This may be understood to mean that (e.g. all of these three] steps are performed responsive to the UE connecting to the primary network cell. Further, it shall be understood that performing and/or controlling the steps of creating the primary data entry and secondary data entry may not be limited to a specific sequence. For example, a secondary data entry in the nested structure may be created together with or after creating the primary data entry.

The expression of responsive to the UE connecting to the primary network cell may be understood to mean that performing the following actions may be caused by the connecting to the primary network cell. In other words, these actions may be performed in reaction to (e.g. in response to, or upon, or when, or after] the UE connecting to the primary network cell. For example, this may be understood as on-time behavior, which may be in contrast to creating a primary data entry and/ or secondary data entry in response to disconnecting from a primary network cell (e.g. after leaving the primary network cell].

For example, a primary data entry and/ or a secondary data entry may both comprise at least two data fields, wherein a first data field is for entering cell identity information and a second data field is for entering connection time information. Creating a primary data entry and/or a secondary data entry may for example be understood to mean that these respective at least two data fields are created respectively generated.

For example, creating a primary data entry and a secondary data entry may be performed after determining a capability of the UE to create the primary data entry and secondary data entry and/or a capability of the UE to support dual-connectivity mode.

Entering cell identity information of the primary network cell in the primary data entry may for example be understood to mean that cell identity information of the primary network cell is entered in a data field of the primary data entry for entering cell identity information. Accordingly, other data fields of the primary data entry (e.g. a second data field for entering connection time information] may be left empty when entering cell identity information of the primary network cell in the primary data entry. In addition or in the alternative, such other data fields of the primary data entry may be filled with dummy information. Such dummy information may be replaced with the intended information e.g. later (e.g. upon a certain event, such as an entering or leaving of a respective network cell]. Before entering cell identity information of the primary network cell, the cell identity information may be obtained at the UE, for example from a network node providing the primary network cell.

For example, a nested data structure may be understood as a data structure that contains several data entries (e.g. at least a primary data entry and a secondary data entry], wherein at least one data entry of these data entries is nested under another data entry of the nested data structure. In some examples, the nested data structure may be referred to as two-dimensional (2D] data structure (e.g. in contrast to a one-dimensional (ID], non-nested data structure]. In an example, the nested data structure may be a MHI data structure (e.g. a 2 D MHI data structure] suitable for logging information on network cell visits of a respective UE. In another example, the nested data structure may be a MHI data structure for cell group types, e.g., master cell group and secondary cell group. Yet in another example, the nested data structure may imply that a data entry is created in association to another data entry (e.g., the secondary data entry is appended to the primary data entry, or e.g. the primary data entry is created semantically with a structure enabling carrying the secondary data entry].

That a secondary data entry is nested under a primary data entry may for example be understood to mean that the primary data entry is associated with (e.g. comprised by or accompanied by] the secondary data entry. For example, the secondary data entry may refer to or may be addressed through the primary data entry. In further examples, that a secondary data entry is nested under a primary data entry may be understood to mean that the primary data entry comprises (e.g. by including, e.g. after inserting or embedding] the secondary data entry and/or the further secondary data entry.

The primary data entry and the secondary data entry nested under the primary data entry may be created (e.g. generated] responsive to connecting the UE to the primary network cell. Accordingly, the nested secondary data entry may be available as soon as the UE is connected to the primary network cell e.g. for logging MHI on one or more UE connections to primary secondary cells.

For example, an alternative approach for logging the visited cells might be in an a-posteriori manner, which means that the cell identity and time a respective UE spent on a cell according to a respective cell visit is logged only after the respective UE has left the particular cell and also that a corresponding data entry is created (e.g. only] after the UE has left the particular cell. However, such an a-posteriori approach may require that a respective data entry exists, since when for example one or more data entries of primary secondary cell visits are nested under a corresponding primary data entry for logging a visit to a primary cell to which the UE is connected while connecting to one or more further primary secondary cells, several primary secondary cells may have been visited before the primary cell is changed. The entry for logging the primary cell visit may thus not exist yet. It follows that the logging (e.g. logs] of such visits of primary secondary cells would have to be temporarily cached in a separate dynamically allocated memory of the UE and these logs would have to be nested under a corresponding primary cell visit data entry until a primary cell change occurs.

Accordingly, the proposed approach of creating respective data entries and entering cell information responsive to connecting a UE to a network cell (in contrast to when disconnecting] may allow for using nested data structures for logging MHI without relying on additional interim storage for entering information on such visited network cells (e.g. primary secondary cell visits].

In the following, further exemplary features and exemplary embodiments of the different aspects of the present disclosure will be described in more detail.

According to an exemplary embodiment of the exemplary aspect, the UE further comprises means for: determining whether the user equipment is in single or dual-connectivity mode upon connection to the primary network cell; responsive to a determination that the user equipment is in dual-connectivity mode with the primary network cell and a primary secondary network cell, entering cell identity information of the primary secondary network cell in the secondary data entry; and responsive to a determination that the user equipment is in single-connectivity mode with the primary network cell, entering dummy cell identity information in the secondary data entry to indicate single-connectivity mode of the user equipment.

An additional check may be carried out for the UE capability to support dual-connectivity mode before storing MHI into a nested data structure, for example after determination that the UE is in single connectivity mode and before creating the nested data structure for that mode. Further considering such an example, responsive to a determination that the UE is in single-connectivity mode with a primary network cell and that dual-connectivity mode is supported, dummy cell identity information may be entered in a secondary data entry to indicate single-connectivity mode of the UE.

After the primary data entry and secondary data entry have been created upon the UE connecting to a primary cell, different exemplary scenarios may be considered depending on whether the UE operates in single- or in dual-connectivity mode. In single-connectivity mode, the UE may (e.g. only] be connected to a primary network cell and not to any primary secondary network cell, while in dualconnectivity mode, the UE may be connected to a primary network cell and simultaneously be connected to a primary secondary network cell.

If, in one example, it is determined that the UE operates in dual-connectivity mode, this may imply that in addition to being connected to a primary network cell, the UE is also connected to a primary secondary network cell, whose visit is to be logged in the MHI. In such a case, cell identity information of the primary secondary network cell to which the UE is connected is entered in the secondary data entry. For example, the cell identity information is entered in the first data field of the secondary data entry for entering cell identity information, while a second data field for entering connection time information is left empty.

If, in another example, it is determined that the UE operates in single-connectivity mode, this may imply that while the UE is already connected to a primary network cell, the UE does not connect to a primary secondary network cell. In such a case, no cell identity information of a primary secondary network cell is available for entering in the secondary data entry. Accordingly, dummy cell identity information may be entered in the secondary data entry e.g. to indicate single-connectivity mode of the UE. For example, such dummy cell identity information may be entered in the first data field of the secondary data entry for entering cell identity information, while a second data field for entering connection time information may be left empty. Therein, a dummy cell identity information may be understood as any kind of information indicating that no actual cell identity information is entered in the corresponding data entry.

According to an exemplary embodiment of the exemplary aspect, the UE further comprises means for: disconnecting the user equipment from the primary secondary network cell and connecting the user equipment to a further primary secondary network cell while remaining connected to the primary network cell; responsive to the user equipment disconnecting from the primary secondary network cell, entering connection time information indicative of a connection time in the primary secondary network cell in the secondary data entry; and responsive to the user equipment connecting to the further primary secondary network cell: creating a further secondary data entry in the nested data structure, wherein the further secondary data entry is nested under the primary data entry; and entering cell identity information of the further primary secondary network cell in the further secondary data entry.

In some examples, when the respective UE operates in dual-connectivity mode, the UE may be connected to a primary network cell and may simultaneously be connected to a primary secondary network cell. In such a case, a secondary data entry nested under a primary data entry has been generated responsive to the UE connecting to the primary network cell and cell identity information of the primary secondary cell has been entered in the secondary data entry. In the event of (i.e. responsive to] disconnecting from the current primary secondary network cell (by the respective UE], connection time information indicative of a connection time in the primary secondary network cell may be entered in the secondary data entry. For example, such connection time information (e.g. a residence time information] indicates or represents a time period during which the UE has been connected to the primary secondary network cell, which may be understood as the time passed between connecting to and subsequently disconnecting from the primary secondary network cell. Together with the corresponding cell identity information of the primary secondary network cell, the time connection information may for example at least partially form the MHI. This may allow for logging the history of network cells visited by a UE over time.

After disconnecting from a primary secondary network cell, a UE operating in dual-connectivity mode may connect to a further primary secondary network cell. In such an example, a further secondary data entry in the nested data structure is created (responsive to the UE connecting to the further primary secondary network cell], wherein the further secondary data entry is nested under the primary data entry. In addition, cell identity information of the further primary secondary network cell is entered in the further secondary data entry. For example, this procedure for the further primary secondary cell may be seen as a repetition of the corresponding procedure for the primary secondary cell, wherein creating the further secondary data entry is however triggered by connecting to a further primary secondary network cell.

According to an exemplary embodiment of the exemplary aspect, the UE further comprises means for: disconnecting the user equipment from the primary secondary network cell while remaining connected to the primary network cell and switching to single-connectivity mode; responsive to the user equipment disconnecting from the primary secondary network cell, entering connection time information indicative of a connection time in the primary secondary network cell in the secondary data entry; and responsive to the user equipment switching to single-connectivity mode: creating a further secondary data entry in the nested data structure, wherein the further secondary data entry is nested under the primary data entry; and entering dummy cell identity information in the further secondary data entry to indicate no dual-connectivity mode of the user equipment.

In some examples, when the UE operates in dual-connectivity mode, the UE may be connected to a primary network cell and may simultaneously be connected to a primary secondary network cell. In such a case, a secondary data entry nested under a primary data entry may have been created (e.g. generated] responsive to the UE connecting to the primary network cell and cell identity information of the primary secondary cell has been entered in the secondary data entry. In the event of (i.e. responsive to] disconnecting from the current primary secondary network cell, connection time information indicative of a connection time in the primary secondary network cell may be entered in the secondary data entry as described above.

After disconnecting from a primary secondary network cell, the UE operating in dual-connectivity mode may switch to single-connectivity mode. In such an example, a further secondary data entry in the nested data structure may be created (responsive to the UE switching to single-connectivity mode], wherein the further secondary data entry is nested under the primary data entry. In addition, dummy (e.g. empty] cell identity information may be entered in the further secondary data entry to indicate no dual-connectivity mode of the UE (i.e. to indicate single-connectivity mode of the UE], It is noteworthy, that such a secondary data entry with dummy cell identity information might already exist in the nested data structure if the UE has already been in single-connectivity mode while being connected to the primary network cell. In an exemplary embodiment, no further such dummy secondary data entry is created in such a case, and the existing dummy secondary data entry is updated based on the additional time spent in single-connectivity mode. In another exemplary embodiment, a further dummy secondary data entry is created in such a case, and the new dummy secondary data entry is updated based on the additional time spent in single-connectivity mode

According to an exemplary embodiment of the exemplary aspect, the UE further comprises means for: connecting the user equipment to a further primary secondary network cell while remaining connected to the primary network cell and leaving single-connectivity mode; responsive to the user equipment leaving single-connectivity mode: entering connection time information indicative of a connection time in singleconnectivity mode in the secondary data entry; and responsive to the user equipment connecting to the further primary secondary network cell: creating a further secondary data entry in the nested data structure, wherein the further secondary data entry is nested under the primary data entry; entering cell identity information of the further primary secondary network cell in the further secondary data entry.

In some examples, when the UE operates in single-connectivity mode, the UE may be connected to a primary network cell and may then switch to dual-connectivity mode when connecting to a further primary secondary network cell. In such a case, a secondary data entry nested under a primary data entry may have been generated responsive to the UE connecting to the primary network cell and dummy cell identity information may have been entered in the secondary data entry. In the event of (i.e. responsive to] leaving single-connectivity mode, connection time information indicative of a connection time in single-connectivity mode may be entered in the secondary data entry. Further, as the UE is newly connected to a further primary secondary network cell after leaving single-connectivity mode, a further secondary data entry nested under the primary data entry may be created responsive to the UE connecting to the further primary secondary network cell and cell identity information of the further primary secondary network cell is entered in the further secondary data entry.

According to an exemplary embodiment of the exemplary aspect, the UE further comprises means for: disconnecting the user equipment from the primary network cell; and entering connection time information indicative of a connection time in the primary network cell in the primary data entry and entering connection time information in at least one of the secondary data entry and the further secondary data entry.

If for example the UE disconnects from the primary network cell, it is to be understood that several connection time information need to be entered. First, connection time information indicative of a connection time in the primary network cell are entered in the primary data entry. Second, connection time information need to be entered in a/the most recent secondary data entry nested under the primary data entry. The most recent secondary date entry which may for example be the secondary data entry or, if present, the further secondary data entry as described above. Depending on whether the UE has been in single-connectivity mode or dual-connectivity mode upon disconnecting from the primary network cell, connection time information for entering in the most recent secondary data entry nested under the primary data entry may be indicative of a connection time in a/the most recent primary secondary network cell or indicative of a connection time in single-connectivity mode as described above.

According to an exemplary embodiment of the exemplary aspect, the primary data entry and/or the secondary data entry and/or the further secondary data entry comprise at least a first data field for entering cell identity information and a second data field for entering connection time information.

For example, at least one of the primary data entry, the secondary data entry or the further secondary data entry may be understood as a tuple (e.g. a finite ordered list or sequence of elements] that contains cell identity information ("cellld”] and connection time information ("timeSpent”] in an exemplary form of {cellldjtimeSpent}.

It may be understood that regarding creating a corresponding data entry comprising at least a first data field and a second data field, the step of creating the data entry may comprise creating the corresponding first data field and second data field. In other words, upon creating a primary data entry and/or a secondary data entry and/or a further secondary data entry, respective first and second data fields contained in the respective data entries are likewise created. Alternatively, the step of creating the data entry may comprise creating the first data field, while the second data field is created upon a specific event, such as leaving a primary network cell or a primary secondary network cell.

Regarding the entering of cell identity information or connection time information in a primary data entry and/or a secondary data entry and/or a further secondary data entry, this may for example be understood as entering cell identity information or connection time information in the respective field for entering cell identity information or for entering connection time information of the respective data entry. In some examples, the primary data entry and/or the secondary data entry and/or the further secondary data entry may comprise further data fields for entering further information (e.g. further information related to logging MHI], For example, such further information may concern further information on a particular network cell (e.g. a primary network cell or a primary secondary network cell to which the UE is connected] and for example connection attributes on a connection to a particular network cell, such as for example reference signal information, frequency band information or beam information.

According to an exemplary embodiment of the exemplary aspect, the cell identity information of the primary network cell and/or of the primary secondary network cell and/or of the further primary secondary network cell is one of: a global cell identity (GCI]; and a physical cell identity [PCI] e.g. with a carrier frequency.

For example, cell identity information of a particular network cell (e.g. a primary network cell or primary secondary network cell] may be a global cell identity (GCI] or physical cell identity (PCI, for example and not necessarily together with a carrier frequency] of this particular network cell that allows for identifying this particular network cell among further network cells. A UE connecting to a network cell may for example obtain cell identity information of this particular network cell upon connecting with the network cell (e.g. by receiving synchronization/broadcast information from a base station providing the particular network cell].

According to an exemplary embodiment of the exemplary aspect, the primary data entry comprises the secondary data entry and/or the further secondary data entry.

For example, that a secondary data entry and/or a further secondary data entry is nested under a primary data entry may be understood to mean that for example the primary data entry comprises (e.g. by including e.g. after inserting or embedding or having a parent-child data relationship] the secondary data entry and/or the further secondary data entry. By the primary data entry comprising the secondary data entry and/or the further secondary data entry, a data structure comprising the primary data entry, the secondary data entry and/or the further secondary data entry may be understood as nested data structure (e.g. a 2D data structure]. In another example, a secondary data entry and/or a further secondary data entry may be contained (e.g. by being included, inserted or embedded] in a primary data entry as an information element.

According to an exemplary embodiment of the exemplary aspect, the user equipment further comprises means for: checking whether the user equipment is capable of dual-connectivity; and creating the nested data structure and corresponding primary and secondary data entries based on the checking.

According to an exemplary embodiment of the exemplary aspect, the user equipment further comprises means for: checking whether the user equipment is capable of dual-connectivity; creating the nested data structure and corresponding primary and secondary data entries based on the checking; and entering actual or obtained values in the created data entries or leaving the created data entries as empty data fields.

For example, a nested data structure (and corresponding primary and secondary data entries] is (e.g. only] created if it is determined (e.g. by checking whether the UE is capable of dual-connectivity] that the UE is capable of a dual-connectivity mode, as disclosed above.

In some examples, a UE may not be capable of dual-connectivity, which may be understood to mean that the UE lacks technical requirements for operating in dual-connectivity mode. In this case, the UE may e.g. lack hardware (e.g. one or more transceivers] for connecting to a primary secondary network cell while being connected to a primary network cell. In such examples, the UE may (e.g. only] be capable of connecting to primary network cells, which may imply that (e.g. only] the visits of primary network cells need to be logged by the MHI. Then, it may not be necessary for the UE to use a nested data structure, because for example a data structure without nested entries (e.g. a one-dimensional list] may be sufficient for logging the visited primary network cells. In such a case, the UE may not perform creating the nested data structure and corresponding primary and secondary data entries, but for example may instead perform creating a non-nested data structure. The checking may be performed and/or controlled prior to the UE connecting to a primary network cell.

According to an exemplary embodiment of the exemplary aspect, the user equipment further comprises means for: checking whether the user equipment is capable of creating a nested data structure.

In some examples, the UE being capable of creating a nested data structure may be understood to mean that the UE is capable of storing MHI for primary network cells as well as primary secondary network cells, e.g. in a memory comprised by or connectable to or accessible by the UE. For example, if it is determined (e.g. by checking whether the UE is capable of creating the nested data structure] that the UE is capable of creating a nested data structure, the UE may proceed and create a nested data structure for creating a primary data entry and a secondary data entry and/or a further secondary data entry as described above. If, in other examples, it is determined (e.g. by checking whether the UE is capable of creating the nested data structure] that the UE is not capable of creating a nested data structure, the UE may use a legacy structure as data structure (e.g. a one-dimensional list] for logging

MHI.

According to an exemplary embodiment of the exemplary aspect, the nested data structure is generated according to a network configuration. Further, a UE according to an exemplary embodiment may further comprise means for: providing capability information of the user equipment to a network node; and receiving the network configuration from the network node, wherein the network configuration is determined at least partially based on the capability information of the user equipment.

It is to be understood that the presentation of the embodiments disclosed herein is merely by way of examples and non-limiting.

Herein, the disclosure of a method step shall also be considered as a disclosure of means for performing the respective method step. Likewise, the disclosure of means for performing a method step shall also be considered as a disclosure of the method step itself.

Other features will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits, for which reference should be made to the appended claims. It should be further understood that the drawings are not drawn to scale and that they are merely intended to conceptually illustrate the structures and procedures described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

Figs, la, b, c show schematic diagrams illustrating an example environment in which exemplary embodiments of the present disclosure may be performed;

Fig. 2 shows a flow chart illustrating an example embodiment of a method according to the present disclosure;

Figs. 3a, b show another flow chart illustrating an example embodiment of a method according to the present disclosure;

Fig. 4 shows a block diagram of an exemplary embodiment of a UE according to the present disclosure; and Fig. 5 shows a schematic illustration of examples of tangible and non-transitory computer- readable storage media.

DETAILED DESCRIPTION OF SOME EXEMPLARY EMBODIMENTS

The following description serves to deepen the understanding and shall be understood to complement and be read together with the description as provided in the above summary section of this specification.

Figs, la to lc show schematic diagrams illustrating an example environment in which exemplary embodiments of the present disclosure may be performed.

Both Fig. la and Fig. lb show the coverage areas of four primary network cells (PCells] labelled A, B, C and D (drawn in different line styles] and controlled by respective MN of an MCG as well as coverage areas of several primary secondary network cells [PSCells] labelled from 1 to 9 and controlled by respective SN of an SCG. As an example, it may be assumed that the shown PCells refer to macrocell deployment and the shown PSCells refer to picocell deployment. The bold solid curved arrow in both Fig. la and Fig. lb illustrates a UE’s trajectory between the two crosses marked along the respective arrows. Therein, the starting point of logging the cells visited by the UE in MR-DC mode may for example be by appearance from IDLE mode (shown in Fig. la] or by entering via handover (shown in Fig. lb].

Referring to the UE’s trajectory shown for the exemplary environment in Fig. la and Fig. lb, the UE may be connected to various PCells and PSCells when moving along this trajectory between the two crosses marked along the respective arrows as shown in the parallel logging of the visited cells according to Fig. lc. As it can be seen from Fig. lc, various exemplary scenarios may appear by switching between singleconnectivity mode and dual-connectivity mode of the UE. For example, the UE may connect to PCell A while being in single-connectivity mode, which means that no PSCell visit has to be logged. In the following, the UE may switch to dual-connectivity mode and connect to PSCell 2 while being connected to PCell A. In another example, the UE may remain in dual-connectivity mode while being connected to a primary cell (e.g. PCell A or PCell B] and then change the PSCell (e.g. from PSCell 2 to PSCell 3 or from PSCell 3 to PSCell 5], In yet another example, the UE may switch from dual-connectivity mode to singleconnectivity mode while being connected to PCell A, which means that the UE disconnects from the current PSCell (e.g. PSCell 7] and afterwards is not connected to any new PSCell. The MHI logs the connection time as the time the UE spent on the various PCells and PSCells, as well as in singleconnectivity mode, as shown in Fig. lc.

One approach for logging the visited cells might be in an a-posteriori manner, which means that the cell identity and time a UE spent on a cell according to a respective cell visit is logged (e.g. only] after the UE has left the particular cell and also that a corresponding data entry is created only after the UE has left the particular cell. However, such an a-posteriori approach may be limited, if for example data entries of PSCell visits are nested under a corresponding data entry for logging a visit to a PCell to which the UE is connected while connecting to one or more PSCells. For example, when several PSCells cells have been visited before the PCell is changed, the entry for logging the PCell visit (i.e. the outer structure, the "nest”] is not existing yet. It follows that the logs of visits of PSCells would have to be temporarily cached in a separate dynamically allocated memory e.g. comprised by or connectable to the UE and these logs would have to be nested under a corresponding PCell visit data entry as soon as a PCell change occurs. The resulting limitations may be considered as follows: an additional interim storage of the PSCell cell visits until a PCell change happens (i.e. an additional memory space] may be needed on UE side; missing PSCell visit information, if for example the UE fails before a PCell change happens.

Fig. 2 is a flow chart 200 illustrating an exemplary embodiment of a method according to the present disclosure. Without limiting the scope of the disclosure, it may be assumed in the following that a UE (e.g. as depicted in Fig. 4] performs the steps/actions of flow chart 200.

In action 210, a UE performs connecting the UE to a primary network cell.

For example, referring to the example environment illustrated in Figs, la to lc, a UE moving along the trajectory shown in Fig. la and Fig. lb may connect to Cell A as primary network cell. For example, this connecting to PCell A could occur by the UE leaving IDLE mode while being located within the coverage area of PCell A (shown in Fig. la] or by entering (e.g. becoming connect to] PCell A via handover from PCell D (shown in Fig. lb].

In action 220, one or more (e.g. three] steps are performed by the UE responsive to the UE connecting to the primary network cell as in action 210, which are creating a primary data entry in a nested data structure, entering cell identity information of the primary network cell in the primary data entry, and creating a secondary data entry in the nested data structure, wherein the secondary data entry is nested under the primary data entry.

For example, referring to the example environment illustrated in Figs, la to lc, the UE may perform creating (e.g. generating] a primary data entry in a nested data structure and entering cell identity information of PCell A (e.g. a global cell identity or a physical cell identity with a carrier frequency] to which the UE has connected in action 210 in this primary data entry. The UE may also perform creating a secondary data entry nested under the primary data entry created upon connecting to PCell A. For example, both the primary data entry and secondary data entry may comprise at least a first data field for entering cell identity information and a second data field for entering time connection information. In the present example, when entering the cell identity information of PCell A in the first data field of the primary data entry, the second data field for entering time connection information is left empty until the connection to the PCell A ends. It is to be understood that one or more of the steps according to action 220 may be performed responsive to connecting the UE to a respective PCell (e.g. PCell A] as primary cell.

In an optional action 230, the UE performs determining whether the UE is in single- or dualconnectivity mode upon connection to the primary network cell. In an optional action 240, responsive to a determining in optional action 230 that the UE is in dual-connectivity mode with the primary network cell and a primary secondary network cell, the UE performs entering cell identity information of the primary secondary network cell in the secondary data entry. In an optional action 250, responsive to a determination in optional action 230 that the UE is in single-connectivity mode with the primary network cell, the UE performs entering dummy cell identity information in the secondary data entry to indicate single-connectivity mode of the UE.

For example, referring to the example environment illustrated in Figs, la to lc, various use cases may occur that may be considered when logging the visited PCells and PSCells.

In one example, after having entered PCell A as primary network cell according to action 210 and after having created a primary data entry and a secondary data entry according to action 220, the UE may determine that it is in single-connectivity mode with PCell A, which means that the UE is currently not connected to any PSCell. In such an example, a dummy cell identity information (e.g. "noPSCell”] may be entered in the first data field of the secondary data entry to indicate single-connectivity mode of the UE. Further, the second data field for entering time information may be left empty until the UE switches from single-connectivity mode to dual-connectivity mode.

In another example, after having entered PCell B as primary network cell according to action 210 and after having created a primary data entry and a secondary data entry according to action 220, the UE may determine that it is in dual-connectivity mode with PCell B and PSCell 3, which means that the UE for example is simultaneously connected to PSCell 3 as primary secondary cell. In such an example, a cell identity information of PSCell 3 is entered in the first data field of the secondary data entry nested under the primary data entry on PCell B. Further, the second data field for entering time information is left empty until the UE leaves PSCell 3.

The primary data entry and the secondary data entry nested under the primary data entry may be created responsive to connecting the UE to the primary network cell. Accordingly, the nested secondary data entry may be available as soon as the UE is connected to the primary network cell for logging MHI on simultaneous UE connections to a respective primary secondary cell. For example, an alternative approach for logging the visited cells might be in an a-posteriori manner, which means that the cell identity and time a UE spent on a cell according to a respective cell visit is logged (e.g. only] after the UE has left the particular cell and also that a corresponding data entry is created (e.g. only] after the UE has left the particular cell. For example, when several primary secondary cells have been visited before the primary cell is changed, the entry for logging the primary cell visit may not be existing yet. It follows that the logs of visits of primary secondary cells would have to be temporarily cached in a separate dynamically allocated memory of the UE and these logs would have to be nested under a corresponding primary cell visit data entry until a primary cell change occurs, e.g. to be provided by the respective UE to the respective network cell.

Accordingly, creating respective data entries and entering cell information responsive to connecting a UE to a network cell (in contrast to when disconnecting] may allow for using nested data structures for logging MHI without relying on additional interim storage for entering information on primary secondary cell visits.

Referring to for example the exemplary embodiment of a method of the exemplary aspect disclosed above in view flow chart 200 of Fig. 2, the present disclosure provides a logging process where the logging of the cell visit information may already be started with entering the respective cell. In contrast to for example an a-posteriori approach, an on-time logging is proposed which enables a nested data structure for MHI logging, wherein for example occurring PSCell visits of a UE can be logged and nested under a data entry of a simultaneous PCell visit before the PCell visit ends.

To give some non-limiting examples of the exemplary aspect, the connecting to a cell by a UE may be divided into two generic cases that distinguish UE transitions between the UE’s radio resource control (RRC] states: when the UE PCell visit is determined by the UE transitioning from RRCJDLE to RRC_CONNECTED; when the UE PCell visit is determined by the UE being in RRC_CONNECTED, but changing the PCell (e.g. through a handover procedure, e.g. RRCReconfiguration with Sync],

In further examples of the exemplary aspect, the process of logging for an entered PCell should be ceased based on two cases of leaving the cell, that distinguish UE transition between the UE’s RRC states: when the UE PCell visit leaving condition is determined by the UE transitioning from RRC_CONNECTED to RRCJDLE; when the UE PCell visit leaving condition is determined by the UE being in RRC_CONNECTED, but changing the PCell to another PCell (e.g. through a handover procedure, e.g. RRCReconfiguration withSync], In further examples of the exemplary aspect, conditions to add and fulfil a new record for MHI logging in dual-connectivity may be: getting connected to a new primary secondary cell (or entering dual-connectivity mode]; changing a primary secondary cell to another one; leaving a primary secondary cell (or leaving dual-connectivity mode].

In further examples of the exemplary aspect, the content of visited cells in MHI logging may be given by: empty records for primary secondary cell identities in case dual-connectivity conditions are not met (i.e. dual-connectivity not activated yet]; empty records for time spent in a primary secondary cell in case the primary secondary cell has not been left yet.

Referring to for example the exemplary embodiment of a method of the exemplary aspect and disclosed above in view of flow chart 200 of Fig. 2, another non-limiting example for the MHI logging process according to the present disclosure is given in the following (if/ else conditions and levels from 1 to 5 are used to make clear the particular steps]:

If a UE operating in MR-DC mode supports storage of two-dimensional nested mobility history information, the UE shall:

1> upon connecting to a new suitable PCell in NR or LTE (RRC_CONNECTED]:

2> include an entry in variable VarMobilityHistoryReport that allows for further nested, possibly after removing the oldest entry, if necessary, according to following: 3> if the global cell identity of the PCell is available:

4> include the global cell identity of that cell in the field visitedPCellld- rl7 of the entry;

3> else:

4> include the physical cell identity and carrier frequency of that cell in the field visitedPCellId-rl7 of the entry;

3> include a further nested entry in variable VarMobilityHistoryReport per PCell entry after removing the oldest entry, if maximum is reached, according to following:

3> if UE operates in single connectivity mode with PCell (no dual-connectivity]:

4> enter dummy field "no PSCell” in the field visitedPSCellId-rl7 of the nested data structure while the field timeSpentPS-rl7 is left empty

3> else (being in dual-connectivity]:

4> if the global cell identity of the PSCell is available:

5> include the global cell identity of that cell in the field visitedPSCellId-rl7 of the entry;

4> else: 5> include the physical cell identity and carrier frequency of that cell in the field visitedPSCell!d-rl7 of the entry;

3> upon getting additionally connected to a PSCell (activating dual-connectivity or changing to a new PSCell (e.g., SN Change procedure]:

4> include timeSpentPS-rl7 of the previous PSCell field irrespective of "no PSCell” or active dual-connectivity;

4> if the global cell identity of the PSCell is available:

5> include the global cell identity of that cell in the field visitedPSCellld- rl7 of the entry;

4> else:

5> include the physical cell identity and carrier frequency of that cell in the field visitedPSCell!d-rl7 of the entry;

3> upon leaving the PSCell (changing to single connectivity]:

4> set the field timeSpentPS-rl7 of the entry as the time spent in the PSCell;

4> enter dummy field "no PSCell” in the field visitedPSCell!d-rl7 of the nested data structure while the field timeSpentPS-rl7 is left empty

2 > upon leaving the PCell:

3> if there is no concurrently visited PSCell:

4> set the field timeSpentPS_rl7 of the dummy field "no PSCell” as time spent without dual-connectivity until the visited PCell is left;

3> else:

4> close last concurrently visited PSCell with setting the field timeSpentPS-rl7 with time spent in the PSCell until the concurrently visited PCell is left;

3> set the field timeSpent-rl7 of the entry as the time spent in the PCell;

In further examples, the UE upon successful RRC connection establishment to the gNB notifies the network about: the UE capability on MHI for PCells; the UE capability (e.g. memory capacity] on MHI for the nested PSCells logging.

According to further examples of the exemplary aspect, based on UE capabilities and based on envisaged use case where MHI is needed, the gNB configures the UE with the 2D-MHI structure via RRCReconfiguration: if the UE is (e.g. only] capable of storing MHI for PCells, it uses legacy structure while generating the MHI; if the UE is capable of storing MHI for PSCells, it uses nested structure as specified by the network. Figs. 3a and 3b show a flow chart 300 illustrating another example embodiment of a method of the exemplary aspect according to the present disclosure. For example, flowchart may be understood as an explanation for the 2D-MHI logging process according to the present disclosure. For exemplary purposes and without limiting the scope of the present disclosure, it may be assumed that a UE (e.g. UE 400 as depicted Fig. 4] performs the steps/actions as shown in the blocks according to flow chart 300.

At block 301, a UE foreseen to operate in dual-connectivity mode is configured to log MHI in a nested data structure (e.g. a 2D data structure]. In other words, the UE may be configured to log nested 2D- MHI. In particular, the UE may be configured by a network based on the UE capability and depending on specific use cases where MHI logging in nested data structure is to be applied.

At block 302, it may be checked whether the UE connects to a primary cell (i.e. PCell] or not. If the UE does not connect to any PCell, this may imply that the UE operates in IDLE mode, wherein it may be not be necessary to actually log MHI in a nested structure (e.g. a 2D data structure]. In this case, the UE may continue with one-dimensional MHI logging (at block 303],

In case the UE connects to a PCell, the method proceeds to block 304, wherein the UE creates a nested data structure (e.g. a 2D data structure]. This step of creating may be performed responsive to the UE connecting to the PCell and may include creating a corresponding primary data entry in the created nested data structure. This created primary data entry may have at least two data fields, wherein for example a first data field is for entering cell identity information (e.g. by means of a field "cellld”, e.g. GCI and/or PCI] and a second data field is for entering connection time information (e.g. by means of a field "timeSpent”]. Accordingly, the created primary data entry may be understood as a tuple {cellldjtimeSpent}. In addition to creating the primary data entry, a secondary data entry is created, wherein the secondary data entry is nested (e.g. as nested data entry] under the primary data entry (e.g. by inserting the secondary data entry as information element in the primary data entry]. Similar to the primary data entry, the secondary data structure may be created with at least two data fields, wherein for example a first data field is for entering cell identity information (e.g. by means of a field "cellld”] and a second data field is for entering connection time information (e.g. by means of a field "timeSpent”]. Accordingly, the created secondary data entry may also be understood as a tuple {cellldjtimeSpent}.

At block 305, a cell identity information of the connected PCell is entered in the "cellld”-data field of the {cellldjtimeSpent} tuple in the primary data entry, while the "timeSpent”-data field is left empty and (e.g. ]only filled upon leaving the connected PCell. For example, the step of block 305 is also reached (e.g. performed] when a handover procedure from another PCell occurs as it could result from block 318 as further described below. At block 306, it is determined whether the UE is simultaneously (i.e. at the same time when the UE is connected to PCell] connected to a primary secondary cell (PSCell], For example, this step may comprise determining whether the UE is in single- or dual-connectivity mode upon connecting to the PCell or has switched from single- to dual-connectivity mode or vice versa. If for example the UE is in single-connectivity mode and thus is not connected to any PSCell, the method proceeds to block 311. If for example the UE is in dual-connectivity mode and thus is connected to a PSCell, the method proceeds to block 307.

At block 307, a cell identity information of the connected PSCell is entered in the "cellld”-data field of the {cellldjtimeSpent} tuple in the secondary data entry, while the "timeSpent”-data field is left empty and only filled upon leaving the connected PSCell.

At block 308, it may be checked whether any changes in the connection between the UE and the PSCell occur, which for example could be the case if the UE disconnects from the PSCell and leaves dualconnectivity mode. In another example, the UE may change from the current PSCell to another PSCell. In such examples of ending the time for which the UE has been connected to the current PSCell, the method may proceed to entering connection time information indicative of a connection time in the PSCell in the "timeSpent”-data field of the {cellldjtimeSpent} tuple of the secondary data entry (block 309],

At block 310, which follows after leaving a PSCell connection and entering a corresponding connection time information at blocks 308 and 309, it may be checked whether the UE changes from the previous PSCell connection to a new PSCell connection (e.g. when the UE remains in dual-connectivity mode] or whether the previous PSCell connection is not followed by a new/ further PSCell connection (e.g. when the UE switches from dual-connectivity mode to single-connectivity mode]. In the latter case, the method proceeds to block 311, otherwise to block 314. In any case, block 310 may include or comprise creating a further secondary data entry, wherein the further secondary data entry is nested (e.g. as nested data entry] under the primary data entry (e.g. by inserting the further secondary data entry as information element in the primary data entry]. Similar to the primary data entry, the further secondary data structure may be created with at least two data fields, wherein for example a first data field is for entering cell identity information (e.g. by means of a field "cellld”] and a second data field is for entering connection time information (e.g. by means of a field "timeSpent”]. Accordingly, the created further secondary data entry may also be understood as a tuple {cellldjtimeSpent}.

At block 311, which follows the case of no connection between the UE and a new PSCell (block 310], dummy cell information (e.g. "noPSCell”] is entered in the "cellld”-data field of the further secondary data entry created at block 310, while the "timeSpent”-data field is left empty and (e.g. only] filled upon the UE leaving the single-connectivity mode. In another example, block 311 may be reached after block 306 described above, which means that no further secondary data entry has been created, because the UE did not connect and subsequently disconnect from any previous PSCell. In such a case, dummy cell information (e.g. "noPSCell”] is entered in the "cellld”-data field of the secondary data entry created at block 304, while the "timeSpent”-data field is left empty and only filled upon the UE leaving the singleconnectivity mode.

At block 312, it may be checked whether the UE may connect to a new PSCell, for example if the UE switches from single-connectivity mode to dual-connectivity mode. In response to such a new PSCell connection occurring, a connection time information indicative of a connection time in singleconnectivity mode is entered at block 313 in the "timeSpent”-data field of the {cellldjtimeSpent} tuple of the secondary data entry (if e.g. the UE previously was not connected to a PSCell, see "No”-branch of block 306] or of the further secondary data entry (if e.g. the UE previously was connected to a PSCell, see "Yes”-branch of block 306], Block 313 is followed by entering a cell identity information of the newly connected PSCell at block 314 in the "cellID”-data field of the {cellldjtimeSpent} tuple in a corresponding new secondary data entry, while the "timeSpent”-data field is left empty in such a new secondary data entry. After block 314, the method may go back to block 308 and continue with checking whether any changes in the connection between the UE and the PSCell occur.

For example, considering the "No”-branches from of blocks 308 or 312, which may imply that no changes in an existing PSCell connection of the UE or no new PSCell connection are found, the method may proceed to block 315. At block 315, it may be checked whether any changes in the connection between the UE and the PCell occur, which may for example be the case when the UE changes to another PCell via a handover procedure or when the UE disconnects from the PCell and enters IDLE mode. If such a change may be detected, the method proceeds to block 316 and block 317.

At block 316, a connection time information is entered in the "timeSpent”-data field of the {cellldjtimeSpent} tuple of a/the most recent secondary data entry. If for example the method arrives at block 316 after the UE being connected to a PSCell (e.g. via the "No”-branch of block 308], the connection time information may be indicative of a connection time in this PSCell. If, in another example, the method arrives at block 316 after the UE not being connected to a PSCell (e.g. via the "No”- branch of block 312], the connection time information may be indicative of a connection time in single connectivity mode. Further at block 317, a connection time information indicative of a connection time in the PCell is entered in the "timeSpent”-data field of the {cellldjtimeSpent} tuple of the primary data entry created in response to connecting to the PCell which the UE had left at block 315. This may for example be the primary data entry created at block 304 as described above.

At block 318, it may be checked whether the UE goes to IDLE mode after leaving the previous PCell connection or not. If the UE goes to IDLE mode, the logging process ends by storing the current nested data structure at the UE at block 319. If the UE does not leave IDLE mode, which may for example be the case of the UE had left the previous PCell via a handover procedure to a new PCell, the method may proceed with creating another primary data entry and another secondary data entry nested under the other primary data entry in the nested data structure, and with entering the cell identity information of the new PCell as described at block 305 above.

Fig. 4 shows a block diagram of an exemplary embodiment of a UE 400 according to the present disclosure. For example, UE 400 may be one of a smartphone, a tablet computer, a notebook computer, a smart watch, a smart band, an loT device or a vehicle.

UE 400 comprises a processor 401. Processor 401 may represent a single processor or two or more processors, which are for example at least partially coupled, for example via a bus. Processor 401 executes a program code stored in program memory 402 (for example program code causing UE 400 to perform one or more of the embodiments of a method according to the present disclosure or parts thereof, when executed on processor 401], and interfaces with a main memory 403. Program memory 402 may also contain an operating system for processor 401. Some or all of memories 402 and 403 may also be included into processor 401.

One of or both of a main memory and a program memory of a processor (e.g. program memory 402 and main memory 403] could be fixedly connected to the processor (e.g. processor 401] or at least partially removable from the processor, for example in the form of a memory card or stick.

A program memory (e.g. program memory 402] may for example be a non-volatile memory. It may for example be a FLASH memory (or a part thereof], any of a ROM, PROM, EPROM, MRAM or a FeRAM (or a part thereof] or a hard disc (or a part thereof], to name but a few examples. For example, a program memory may for example comprise a first memory section that is fixedly installed, and a second memory section that is removable from, for example in the form of a removable SD memory card.

A main memory (e.g. main memory 403] may for example be a volatile memory. It may for example be a DRAM memory, to give non-limiting example. It may for example be used as a working memory for processor 401 when executing an operating system, an application, a program, and/or the like.

Processor 401 further controls a communication interface 404 (e.g. radio interface] configured to receive and/or transmit data and/or information. For example, communication interface 404 may be configured to transmit and/or receive radio signals to/from a network node, such as a base station. It is to be understood that any computer program code based processing required for receiving and/ or evaluating radio signals may be stored in an own memory of communication interface 404 and executed by an own processor of communication interface 404 and/or it may be stored for example in memory 403 and executed for example by processor 401. Communication interface 404 may in particular be configured to communicate according to a cellular communication system like a 2G/3G/4G/5G or future generation cellular communication system. UE 400 may use radio interface 404 to communicate with a base station, e.g. a network node depicted in Fig. 5.

For example, the communication interface 404 may further comprise a BLE (Bluetooth Low Energy] and/or Bluetooth radio interface including a BLE and/or Bluetooth transmitter, receiver or transceiver. For example, radio interface 404 may additionally or alternatively comprise a WLAN (Wireless Local Area Network] radio interface including at least a WLAN transmitter, receiver or transceiver.

The components 402 to 404 of UE 400 may for example be connected with processor 401 by means of one or more serial and/or parallel busses.

It is to be understood that UE 400 may comprise various other components. For example, UE 400 may optionally comprise a user interface (e.g. a touch-sensitive display, a keyboard, a touchpad, a display, etc.].

Fig. 5 is a schematic illustration of examples of tangible and non-transitory computer-readable storage media according to the present disclosure that may for example be used to implement memory 402 of Fig. 4. To this end, Fig. 5 displays a flash memory 500, which may for example be soldered or bonded to a printed circuit board, a solid-state drive 501 comprising a plurality of memory chips (e.g. Flash memory chips], a magnetic hard drive 502, a Secure Digital (SD] card 503, a Universal Serial Bus (USB] memory stick 504, an optical storage medium 505 (such as for example a CD-ROM or DVD] and a magnetic storage medium 506.

In the present specification, any presented connection in the described embodiments is to be understood in a way that the involved components are operationally coupled. Thus, the connections can be direct or indirect with any number or combination of intervening elements, and there may be merely a functional relationship between the components.

Moreover, any of the methods, processes and actions described or illustrated herein may be implemented using executable instructions in a general-purpose or special-purpose processor and stored on a computer-readable storage medium (e.g., disk, memory, or the like] to be executed by such a processor. References to a ‘computer-readable storage medium’ should be understood to encompass specialized circuits such as FPGAs, ASICs, signal processing devices, and other devices.

The expression "A and/or B” is considered to comprise any one of the following three scenarios: (i] A, (ii] B, (hi] A and B. Further, the expression "A and/or B” is considered to comprise also the expression "at least one of A and B”. Furthermore, the article "a” is not to be understood as "one”, i.e. use of the expression "an element” does not preclude that also further elements are present. The term "comprising” is to be understood in an open sense, i.e. in a way that an object that "comprises an element A” may also comprise further elements in addition to element A.

It will be understood that all presented embodiments are only exemplary, and that any feature presented for a particular example embodiment may be used with any aspect on its own or in combination with any feature presented for the same or another particular example embodiment and/or in combination with any other feature not mentioned. In particular, the example embodiments presented in this specification shall also be understood to be disclosed in all possible combinations with each other, as far as it is technically reasonable and the example embodiments are not alternatives with respect to each other. It will further be understood that any feature presented for an example embodiment in a particular category (method/apparatus/computer program/ system] may also be used in a corresponding manner in an example embodiment of any other category. It should also be understood that presence of a feature in the presented example embodiments shall not necessarily mean that this feature forms an essential feature and cannot be omitted or substituted.

The statement of a feature comprises at least one of the subsequently enumerated features is not mandatory in the way that the feature comprises all subsequently enumerated features, or at least one feature of the plurality of the subsequently enumerated features. Also, a selection of the enumerated features in any combination or a selection of only one of the enumerated features is possible. The specific combination of all subsequently enumerated features may as well be considered. Also, a plurality of only one of the enumerated features may be possible.

The sequence of all method steps presented above is not mandatory, also alternative sequences may be possible. Nevertheless, the specific sequence of method steps exemplarily shown in the figures shall be considered as one possible sequence of method steps for the respective embodiment described by the respective figure.

The subject-matter has been described above by means of example embodiments. It should be noted that there are alternative ways and variations which are obvious to a skilled person in the art and can be implemented without deviating from the scope of the appended claims. LIST OF ABBREVIATIONS

UE User equipment

MHI Mobility history information

3GPP 3rd Generation Partnership Project

NR New radio

Al Artificial intelligence

ML Machine learning

MR-DC Multi-radio dual-connectivity

PCell Primary cell

MN Master node

MCG Master cell group

PSCell Primary secondary cell

SN Secondary node

SCG Secondary cell group

LTE Long Term Evolution

E-UTRA Evolved Universal Terrestrial Radio Access eNB eNodeB gNB gNodeB

EN-DC E-UTRA-NR dual connectivity

GCI Global cell identity

PCI Physical cell identity

RRC Radio resource control

Claims

C l a i m s A user equipment comprising means for: connecting the user equipment to a primary network cell; responsive to the user equipment connecting to the primary network cell: creating a primary data entry in a nested data structure; entering cell identity information of the primary network cell in the primary data entry; and creating a secondary data entry in the nested data structure, wherein the secondary data entry is nested under the primary data entry. The user equipment according to claim 1, wherein the user equipment further comprises means for: determining whether the user equipment is in single- or dual-connectivity mode upon connection to the primary network cell; responsive to a determination that the user equipment is in dual-connectivity mode with the primary network cell and a primary secondary network cell, entering cell identity information of the primary secondary network cell in the secondary data entry; responsive to a determination that the user equipment is in single-connectivity mode with the primary network cell, entering dummy cell identity information in the secondary data entry to indicate single-connectivity mode of the user equipment. The user equipment according to claim 2, wherein the user equipment further comprises means for: disconnecting the user equipment from the primary secondary network cell and connecting the user equipment to a further primary secondary network cell while remaining connected to the primary network cell; responsive to the user equipment disconnecting from the primary secondary network cell, entering connection time information indicative of a connection time in the primary secondary network cell in the secondary data entry; and responsive to the user equipment connecting to the further primary secondary network cell: creating a further secondary data entry in the nested data structure, wherein the further secondary data entry is nested under the primary data entry; and entering cell identity information of the further primary secondary network cell in the further secondary data entry. The user equipment according to claim 2, wherein the user equipment further comprises means for: disconnecting the user equipment from the primary secondary network cell while remaining connected to the primary network cell and switching to single-connectivity mode; responsive to the user equipment disconnecting from the primary secondary network cell, entering connection time information indicative of a connection time in the primary secondary network cell in the secondary data entry; and responsive to the user equipment switching to single-connectivity mode: creating a further secondary data entry in the nested data structure, wherein the further secondary data entry is nested under the primary data entry; and entering dummy cell identity information in the further secondary data entry to indicate no dual-connectivity mode of the user equipment. The user equipment according to claim 2, wherein the user equipment further comprises means for: connecting the user equipment to a further primary secondary network cell while remaining connected to the primary network cell and leaving single-connectivity mode; responsive to the user equipment leaving single-connectivity mode: entering connection time information indicative of a connection time in singleconnectivity mode in the secondary data entry; and responsive to the user equipment connecting to the further primary secondary network cell: creating a further secondary data entry in the nested data structure, wherein the further secondary data entry is nested under the primary data entry; and entering cell identity information of the further primary secondary network cell in the further secondary data entry. The user equipment according to any of the preceding claims, wherein the primary data entry and/or the secondary data entry and/or the further secondary data entry comprise at least a first data field for entering cell identity information and a second data field for entering connection time information. The user equipment according to any of the preceding claims, wherein the cell identity information of the primary network cell and/or of the primary secondary network cell and/or of the further primary secondary network cell is one of: a global cell identity; and a physical cell identity with a carrier frequency. The user equipment according to any of the preceding claims, wherein the primary data entry comprises the secondary data entry and/or the further secondary data entry.

9. The user equipment according to any of the preceding claims, wherein the user equipment further comprises means for: checking whether the user equipment is capable of dual-connectivity; and - creating the nested data structure and corresponding primary and secondary data entries based on the checking.

10. A method comprising: connecting a user equipment to a primary network cell; - responsive to the user equipment connecting to the primary network cell: creating a primary data entry in a nested data structure; entering cell identity information of the primary network cell in the primary data entry; and creating a secondary data entry in the nested data structure, wherein the secondary data entry is nested under the primary data entry.