Timing advance measurement in layer 1 / layer 2-triggered mobility and conditional layer 1 / layer 2-triggered mobility

Abstract

A method of operating a communication device is provided. The communication device is configured with a LTM candidate cell and a serving cell that belong to a same TA measurement group. The method can include determining that a condition has been met. The method can further include, responsive to determining that the condition has been met, performing a timing advance ("TA") measurement procedure for a layer 1 / layer2-triggered mobility ("LTM") candidate cell prior to receiving a LTM cell switch command. There is also provided a communication device, a computer program and a computer program product.

Description

P111802W001TIMING ADVANCE MEASUREMENT IN LAYER 1 / LAYER 2-TRIGGERED MOBILITY AND CONDITIONAL LAYER 1 / LAYER 2-TRIGGERED MOBILITYTECHNICAL FIELDThe present disclosure is related to wireless communication systems and more particularly performing a timing advance, TA, measurement procedure for a layer l / layer2 -triggered mobility, LTM, candidate cell.BACKGROUND

[0001] The present disclosure is related to wireless communication systems and more particularly to communication device-based timing advance (“TA”) measurement in layer 1 / layer 2-triggered mobility (“LTM”) and conditional LTM.

[0002] FIG. 1 illustrates an example of a new radio (“NR”) network (e.g., a 5th Generation (“5G”) network) including a 5G core (“5GC”) network 130, network nodes 120a-b (e.g., 5G base station (“gNB”)), multiple communication devices 110 (also referred to as user equipment (“UE”)).

[0003] UEs within a cell can be located at varying distances and positions from a base station. Therefore, the transmissions from different UEs experience different delays until reception at the base station. The reception of these uplink (“UL”) transmissions at the base station within the related reception window can be ensured by UL a timing control procedure, which can be referred to as time alignment. This procedure can help reduce the intracell interference that occurs among the UEs transmitting in consecutive subframes and / or adjacent subcarriers. Time alignment of the UL transmissions can be accomplished by adjusting the UE transmitter's timing relative to the timing of downlink reception, primarily to offset propagation delays among different UEs.

[0004] The time alignment for UL synchronization can be carried out by calculation of a timing advance (“TA”) value at the base station and is indicated to the UE. The TA value may be represented as an actual timing adjustment value and / or an index pointing to a timing adjustment value. During the initial cell access, the UE can perform the random-access (“RA”) procedure in which the received PRACH preamble (e.g., Msgl) is used by the base station to calculate the UE’s initial TA value for UL transmissions within the cell. The TA value can be later used by the UE in sending the UL transmissions to the base station. Throughout the connection, the UE can be continuously monitored by the base station to check whether anyP111802W001 adjustments are needed in the UE’s TA value to compensate for the changes in propagation delay. The UE can be indicated if there is a requirement to modify the TA value.

[0005] When there is no UL transmission by the UE for some duration in the serving cell, the previously acquired TA value may not be valid anymore, possibly due to the UE's movement leading to changes in propagation delay. In that case, an UL transmission with the inaccurate TA value results in reception outside the receive window at the base station, resulting in incorrect reception or even interference with the other UL transmissions. This can be prevented by configuring and applying a timer known as the timeAlignmentTimer (also termed as a Time alignment timer). This timer can indicate the duration during which the UE can consider itself synchronized with the uplink timing of the serving cell without receiving any updates in the TA value. Once the time alignment timer expires and the TA values are not updated, the UE is no longer regarded as UL synchronized to the serving cell.

[0006] LTM is an inter-cell mobility procedure, proposed in 3GPP Rel-18, to reduce the overall handover latency by leveraging lower layer signaling. To achieve this, the UE can be configured with a RRC configuration of one or multiple LTM candidate cells. Then the UE can performs LI -reference signal received power (“RSRP”) measurements on the synchronization signal block (“SSBs”) (e.g., beams) of the configured LTM candidate cells and report the measurement over user control information (“UCI”) via a physical uplink control channel (“PUCCH”) or physical uplink shared channel (“PUSCH”). The reduction in handover interruption can be attained by means of early uplink UL and downlink DL synchronization with the target cell before the transmission of LTM cell switch MAC CE.

[0007] The DL pre-synchronization refers to the pre-activation of certain transmission configuration indicator (“TCI”) states in the LTM candidate cells before any of those cells becomes the target cell. DL pre-synchronization reduces the overall duration required for cellsearch, fine-tracking, and acquisition of SSB-based RRM Measurement Timing Configuration window (“SMTC”), and the time spent in SSB post-processing, thus facilitating a faster cell switch.

[0008] The UL pre-synchronization corresponds to the early acquisition of LTM candidate cell TA value before the UE switches to that cell. The early UL synchronization allows the UE to switch to the LTM candidate cell upon receiving the LTM cell switch indication, without any RA. Furthermore, early TA acquisition procedure is not required for an LTM candidate cell if the applied TA value for the LTM candidate cell is the same as the serving cell or the LTM candidate cell has an applicable TA value equal to “0”. An example of an UL presynchronization procedure is illustrated in FIG. 2.P111802W001

[0009] At block 210 and block 220, a serving cell (e.g., Cell A) transmits a RRC Reconfiguration message to a UE, which returns a RRC reconfiguration complete message. At block 230, a serving cell (e.g., Cell A) transmits a PDCCH order to the UE, which includes information about the RA for TA acquisition. At block 240, the UE transmits the PRACH preamble to the LTM candidate cell (e.g., Cell B), according to the indicated PDCCH order. The LTM candidate cell (e.g., Cell B) calculates the TA values, according to the PRACH preamble received and then sends the TA value to the serving cell. At block 250, the TA value is provided to the UE via cell a switch MAC CE during the eventual LTM handover execution.

[0010] The UE may not be required to maintain the TA timer for the LTM candidate cell in this context and it is up to the network implementation to determine the TA validity.

[0011] Rel-18 also describes a possibility to perform UE-based TA measurements on the LTM candidate cells, as configured by RRC. In some examples, the UE can measure the TA value for the given LTM candidate cell by itself and can switch to the LTM candidate cell without any PRACH transmission, upon receiving the LTM cell switch media access control (“MAC”) control element (“CE”) indication. The UE then applies the TA value calculated by itself if no TA values are explicitly indicated in the LTM cell switch MAC CE. The configuration to perform the UE-based TA measurement for a given LTM candidate cell is provided to the UE as part of the LTM-Candidate and LTM-Config IES, via Itm-UE- MeasuredTA-ID and Itm-ServingCellUE-MeasuredTA-ID respectively. Both parameters are used by the UE to determine whether the UE-based TA measurements can be performed towards the associated LTM candidate cell or not. If the value stored in Itm-ServingCellUE-MeasuredTA-ID at the serving cell equals the value of Itm-UE-MeasuredTA-ID for a certain LTM candidate cell, the UE is considered to be configured with UE-based TA measurement if an LTM cell switch is executed for this LTM candidate configuration.

[0012] Conditional handover (“CHO”) and the related conditional mobility procedures were introduced in NR for improving the mobility robustness by preparing the UE (and the CHO candidate cells) in advance before there are any radio link outages. The UE is provided the RRC configuration of the candidate CHO cells, like LTM, and some CHO execution conditions, which once fulfilled lead the UE to directly perform the handover without sending measurement report to the network, unlike LTM. However, there are other differences between the legacy CHO and LTM, for example, the CHO does not include the procedures of early UL and DL synchronization as in LTM Rel-18.

[0013] To facilitate both the advantages of short handover interruption as well as better robustness, Rel-19 aims to introduce Conditional LTM as part of the mobility-related enhancements.P111802W001

[0014] In Conditional LTM, the UE is configured with the conditional LTM execution conditions along with the LTM candidate cell configuration. The UE may perform early UL and DL synchronization procedures before the cell switch and shall execute LTM cell switch upon the fulfillment of the provided execution conditions.SUMMARY

[0015] Certain aspects of the disclosure and their embodiments may provide solutions to these or other challenges. The embodiments provide a method for performing a timing advance measurement procedure for a layer 1 / layer 2-triggered mobility, LTM, candidate cell. Some embodiments are directed to conditional layer 1 / layer 2-triggered mobility.

[0016]

[0017] According to some embodiments, a method of operating a communication device is provided. The communication device is configured with a LTM candidate cell and a serving cell that belong to a same TA measurement group. The method can include determining that a condition has been met. The method can further include, responsive to determining that the condition has been met, performing a timing advance (“TA”) measurement procedure for a layer l / layer2 -triggered mobility (“LTM”) candidate cell prior to receiving a LTM cell switch command. In some embodiments determining that the condition has been met comprises one or more of-determining that the condition has been met based on a radio measurement of the LTM candidate cell or a serving cell of the communication device,-determining that the communication device received the communication device-based TA measurement configuration,-determining that a LTM measurement report has been triggered for the LTM candidate cell,-detecting a radio link failure,-executing LTM fast failure recover to the LTM candidate cell,-determining that the communication device received a transmission configuration indicator, TCI, state activation command media access control, MAC, control element, CE, for the LTM candidate cell,-determining that the communication device received a physical downlink control channel, PDCCH, order to transmit physical random access channel, PRACH, preamble for the LTM candidate cell, and-determining that the communication device has transmitted a PRACH preamble to theLTM candidate cell.P111802W001

[0018] In some embodiments where the communication device is configured with one or more conditional LTM, CLTM, execution conditions for the LTM candidate cell, determining that the condition has been met comprises one or more of-determining that at least one of the one or more CLTM execution conditions has been met, -determining that all of the CLTM execution conditions have been met,-determining that the communication device received a scheduling request, SR, configuration or pre-allocated uplink, UL, grant for the LTM candidate cell, and-determining that the communication device received an indication to activate the SR configuration or the pre-allocated uplink, UL, grant for the LTM candidate cell

[0019] According to other embodiments, a communication device, a computer program, computer program product, non-transitory computer readable medium, host, or system is provided to perform one of the above methods.

[0020] Certain embodiments may provide one or more of the following technical advantages. In some embodiments, the UE has a self-measured valid TA value associated to the LTM candidate cell(s) available before LTM cell switch execution (e.g., before the UE receives the LTM cell switch MAC CE or CLTM execution conditions are met), which ensures a RACH- less access to the candidate target cell in a shorter interruption time.

[0021] In additional or alternative embodiments, the TA value measured by the UE is accurate and valid after cell switch to the candidate target cell which in turn decreases the probability of erroneous UL reception at the network after LTM execution.

[0022] By determining the correct conditions for starting to measure the TA value for an LTM candidate cell, it is possible to obtain better accuracy in the UE-measured TA value and a faster LTM cell switch procedure.

[0023] By determining the correct conditions for starting to measure the TA value for an LTM candidate cell, it is possible to avoid, in case of an LTM cell switch, the UE and network being out of synchronization, since the measured TA value happened too early, and the measured TA value may not be valid anymore. This will also avoid failure of the LTM cell switch procedure and thus a longer connectivity interruption.BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The accompanying drawings, which are included to provide a further understanding of the disclosure and are incorporated in and constitute a part of this application, illustrate certain non-limiting embodiments of inventive concepts. In the drawings:

[0025] FIG. l is a schematic diagram illustrating an example of a 5thgeneration (“5G”) network;P111802W001

[0026] FIG. 2 is a signal flow diagram illustrating an example of a UL pre-synchronization procedure;

[0027] FIG. 3 is a flow chart illustrating an example of operations performed by a communication device in accordance with some embodiments;

[0028] FIG. 4 is a block diagram of a communication system in accordance with some embodiments;

[0029] FIG. 5 is a block diagram of a user equipment in accordance with some embodiments;

[0030] FIG. 6 is a block diagram of a network node in accordance with some embodiments; and

[0031] FIG. 7 is a block diagram of a virtualization environment in accordance with some embodiments.DETAILED DESCRIPTION

[0032] 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, in which examples of embodiments of inventive concepts are shown. Inventive concepts may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of present inventive concepts to those skilled in the art. It should also be noted that these embodiments are not mutually exclusive. Components from one embodiment may be tacitly assumed to be present / used in another embodiment.

[0033] Layer 1 / Layer 2-triggered mobility (“LTM”) was introduced in Rel-18 and can offer improvements in handover latency and interruption time compared to Layer 3 based mobility. However, LTM as introduced in Rel-18 also has a number of limitations compared to Layer 3 mobility. The Rel-19 work item aims to remove a number of these limitations. Layer 3 mobility uses layer 3 measurement reporting which supports UE evaluated events for triggering of measurement reports and reduces signaling overhead compared to periodic measurement reporting. Such event triggering is not supported by the LI measurements that are used for LTM mobility.

[0034] There currently exist certain challenges. In some examples, it is possible to configure a UE with a UE-based TA measurement configuration for one or more LTM candidate cell(s). This configuration can be based on the concept that one or more LTM candidate cell(s) can be time synchronized with each other and / or with the serving cell and / or be co-locatedP111802W001 and / or share some deployment and / or equipment. Therefore, the UE itself can measure the TA value for an LTM candidate cell without performing a random-access procedure with the candidate cell. An example of such UE-based measurement can be that UE calculates the TA value for an LTM candidate cell, which is in the same TA measurement group as the serving cell, based on the TA value associated to the serving cell and the estimated difference in the reception timing of the serving cell and the LTM candidate cell reference signals. The UE performs UE-based TA measurement for LTM candidate cell(s) after being configured by RRC and applies the calculated TA value to execute a RACH-less LTM upon receiving the LTM cell switch command. However, it is unknown when the UE should start to measure the TA value for an LTM candidate cell by itself.

[0035] The LTM execution is conditioned upon receiving the LTM cell switch MAC CE command, therefore the UE does not know whether it is too early or too late to start measuring the TA value for an LTM candidate cell by itself. It is possible that the UE calculates the TA value for an LTM candidate cell too early, e.g., right after receiving the LTM candidate cell configuration and determining that it is possible to perform UE-based TA measurement for one or more LTM candidate cell(s). In that case, it is possible that the TA value measured by the UE becomes inaccurate after some duration due to possible changes in UE position and direction relative to the LTM candidate cell (e.g., due to the UE moving with a certain speed). Therefore, the UE would be required to repeat the UE-based TA measurement procedure for the given LTM candidate cell, which is not cost-effective in terms of UE energy consumption. If the UE does not update the TA value measured by itself and the previously measured TA value becomes inaccurate by the time UE receives the LTM cell switch MAC CE, it may result in erroneous UL transmissions to the new serving cell (previously LTM candidate cell) after LTM execution, generating interference in the uplink.

[0036] If the UE starts too late to measure the TA value, the UE may receive an LTM cell switch command but not have an available TA value measured by itself which may result in longer interruption time in sending the RRC Reconfiguration Complete message and / or any other UL data to the LTM candidate cell (which is now the new source cell), due to the TA value being measured by the UE after the reception of LTM cell switch command.

[0037] In Conditional LTM (“CLTM”), the LTM cell switch is executed upon the fulfilment of a CLTM execution condition and there is no LTM cell switch MAC CE command containing a valid TA value for the LTM candidate cell. In the case of Conditional LTM, it is again necessary that the UE measures the LTM candidate cell TA value by itself (if configured) before the LTM execution for a shorter connectivity interruption. A similar issue (as mentioned in theP111802W001LTM part) exists in Conditional LTM because the CLTM execution conditions may be fulfilled any time after the configuration of Conditional LTM and the associated execution conditions.

[0038] Various embodiments herein address some of these challenges by a UE monitoring a condition for performing a UE-based TA measurement procedure. In some examples, the UE is provided UE-based TA measurements configuration for one of more LTM candidate cell(s) and the LTM candidate cell(s) belong to the same TA measurement group as the current serving cell of the UE. The UE performs UE-based TA measurements procedure before in order to have a RACH-less LTM cell switch such that the measured TA value is both accurate and valid after cell switch to the LTM candidate cell.

[0039] In some embodiments, the UE first establishes whether the serving cell and the LTM candidate cell(s) belong to the similar TA measurement group or not. If both the serving cell and LTM candidate cell share an identical TA measurement group (i.e., the values stored in Itm-UE- MeasuredTA-ID and Itm-ServingCellUE-MeasuredTA-ID are the same for an LTM candidate cell and the serving cell respectively), the UE determines to start performing UE-based TA measurements on that LTM candidate cell based on a UE implementation with is based one or more conditions. The UE starts monitoring the conditions, as explained in the detailed description of the proposed solution, to make observations about the fulfillment of one or more condition(s) for measuring the TA value associated with the LTM candidate cell. In short, the proposed embodiments can indicate when the UE should start to evaluate the TA value for LTM candidate cells on its own.

[0040] Embodiments applicable for LTM are described below. The term “L1 / L2 based inter-cell mobility (LTM)” as defined in Release 18 is used herein. However, the term is used interchangeably with the terms L1 / L2 mobility, Ll-mobility, LI based mobility, Ll / L2-centric inter-cell mobility, L1 / L2 inter-cell mobility Ll / L2-Triggered Mobility (LTM), Lower-layer triggered Mobility or simply LTM.

[0041] In some embodiments, the UE receives a lower layer signaling from the network (e.g., a MAC Control Element - MAC CE) indicating to the UE a change (or switch or activation) of its serving cell (i.e., PCell or PSCell), wherein a lower layer signaling is a message / signaling carried via a lower layer protocol, which may be referred as a L1 / L2 intercell mobility execution command or LTM cell switch command. Before the UE receives the LTM cell switch command, the UE is configured by the network with one or more LTM candidate cell configurations (e.g., reception of an RRC Reconfiguration message, with at least one LTM candidate cell configuration). An LTM candidate cell configuration may include parameters in the IE CellGroupConfig per candidate cell and / or an embedded RRC Reconfiguration per LTM candidate cell.P111802W001

[0042] The term LTM cell switch procedure can refer to the process of a UE switching (or changing) its cell from a source cell to a target cell (which may be called here an LTM candidate cell or a neighbor cell), using a lower layer mobility procedure. In the context of LTM, an LTM cell switch procedure may sometimes also be known as L1 / L2 based inter-cell mobility execution, LTM cell switch execution, LTM execution, dynamic switch, LTM switch, (LTM) cell switch, (LTM) serving cell change or (LTM) cell change. In the context of the invention, switching to the LTM candidate cell configuration comprises the UE considering that an LTM candidate cell becomes its new special cell (“SpCell”) e.g., PCell in case of LTM being configured for a Master Cell Group (“MCG”) and / or PSCell in case of LTM being configured for a Secondary Cell Group (“SCG”).

[0043] An LTM cell switch procedure or LTM execution procedure may be triggered in the UE by reception of an LTM cell switch command (e.g., LTM Cell Switch MAC CE), or alternatively, triggered in response to the detection of a failure (in case of LTM fast failure recovery). The text refers to an LTM candidate cell, which is a cell the UE is configured with when configured with L1 / L2 -triggered mobility. That is a cell the UE can move to in an LTM cell switch procedure, upon reception of an LTM cell switch command. These cells may also be termed as candidate cell(s), candidates, candidate target cell, implied target cell, mobility candidates, non-serving cells, additional cells, or deactivated cells etc. An LTM candidate cell might also pertain to a candidate cell in a 5G Radio Access Technology like NR or a future 6G Radio Access Technology.

[0044] An LTM candidate cell is a cell the UE may be configured to perform lower layer measurements, such as Layer 1 (“LI”) reference signal received power (“RSRP”), on the synchronization signal block (“SSB”) and / or channel state information reference signal (“CSI- RS”), e.g., LTM CSI measurements. Lower layer measurements, in this context (and the context of Conditional LTM as explained later), are measurements reported to support lower layer procedures like beam management, TCI state activations / deactivations, early timing advance (“TA”) acquisition, and link adaptation, and they aren't filtered based on Layer 3 (“L3”) parameters, though there may (or may not) be some filtering of these measurements based on lower layer parameters. The UE reports these measurements, and the network takes educated decision on which beam (e.g., TCI state) and / or cell the UE is to be switched to. In the case of an LTM fast failure recovery, when a failure is detected, the UE selects a cell and when the cell is an LTM candidate cell the UE does not have to perform re-establishment, but instead performs an LTM cell switch towards the selected LTM candidate cell e.g., by applying the LTM candidate cell configuration associated to the selected LTM candidate cell.P111802W001

[0045] Embodiments applicable for Conditional LTM (“CLTM”) are described below. Similar embodiments to those applicable to LTM can be applicable to CLTM, which may be viewed as a form of conditional reconfiguration. In CLTM, the UE is configured with an LTM candidate cell (denoted as a CLTM candidate cell), by receiving an LTM candidate cell configuration, as in legacy LTM, and called herein a Conditional LTM candidate cell configuration, and an associated execution condition, denoted CLTM execution condition. The CLTM execution condition associated to a CLTM candidate cell is associated to the assessment of lower layer measurements, such as Layer 1 (“LI”) RSRP and / or SS-RSRP, derived from SSBs and / or CSI-RSs of either the source cell and / or an CLTM candidate cell. The reception of CLTM execution condition may also involve receiving an indication of the condition and / or configuring it with parameters such as event identified s), offset(s), threshold(s), reference signal (RS) type, trigger quantity, time-to-trigger (“TTT”), and so forth.

[0046] When configured with CLTM, the UE evaluates the CLTM execution condition (referred to as Conditional LTM execution condition, LTM execution condition, or triggering condition) or a combination thereof. And, when the condition for a CLTM candidate cell is fulfilled, the UE performs a CLTM execution, which may be seen as a kind of LTM execution (but not triggered by the reception of an LTM cell switch command); this may also be considered as a kind of LTM cell switch, or Conditional LTM cell switch, or Conditional LTM execution. During the execution, the UE may apply a message, parts of a message, or at least one information element (IE), or perform a source cell switch or change. According to the methods outlined in the invention, upon satisfaction of the execution condition(s), the UE initiates an LTM cell switch.

[0047] A LTM candidate cell within the framework of CLTM may be referred to as a Conditional LTM candidate cell, CLTM cell, candidate cell, candidate target cell, target cell, LTM candidate cell, or L1 / L2 inter-cell mobility candidate cell, depending on the context. Essentially, it denotes a cell to which the UE is directed or switches in the event of executing a conditional L1 / L2 inter-cell mobility procedure after meeting the associated execution condition(s). These cells may also be termed as candidate cells, mobility candidates, non-serving cells, additional cells, or deactivated cells. A Conditional LTM candidate cell may also be a currently configured as a serving cell, i.e., an SCell from MCG or an SCell from SCG or PSCell. A Conditional LTM candidate cell might also pertain to a candidate cell in a 5G Radio Access Technology like NR or a future 6G Radio Access Technology.

[0048] In the context of both LTM and CLTM, the term “beam” may correspond to a spatial direction in which a Reference signal (“RS”), such as Synchronization Signal Block-RS (“SSB- RS”), Mobility Reference Signal (“MRS”), a Channel State Information - RS (‘CSI-RS”), or aP111802W001RS defined for a 6G radio interface, is transmitted (e.g., by a network node) or received (e.g. by the UE), or a spatial filter applied to a signal which is transmitted or received. Thus, transmitting signals in different beams could correspond to transmitting signals in different spatial directions. The beam measurement may correspond to a measurement on an RS transmitted in that beam e.g., an SSB measurement and involves determining a measurement quantity value such as a Synchronization Signal based Reference Signal Received Power (“SS-RSRP”) and / or Synchronization Signal based Reference Signal Received Quality (“SS-RSRQ”) and / or Synchronization Signal based Signal to Noise and Interference Ratio (“SS-SINR”). In the text the beam is identified by beam index and / or a Reference Signal (“RS”) index or identifier, such as an SSB index, or a CSI-RS resource identifier.

[0049] Both LTM and CLTM may be associated with a RACH-less LTM execution procedure in which the UE does not transmit a Physical Random-Access Channel (“PRACH”) preamble to the LTM candidate cell as its first UL message. In other words, the UE has either acquired the applicable TA value for the LTM candidate cell before LTM cell switch or has measured the appliable TA value for the LTM candidate cell by itself, it the UE is configured with UE-based TA measurement procedure. Furthermore, the UE either i) transmits a Scheduling Request (SR) over the Physical Uplink Control Channel (PUCCH), or any other UL control channel which requires the UE to be UL synchronized (or UL time aligned); or ii) transmits UL payload (bits associated to a complete message, e.g., RRC Reconfiguration Complete), e.g., using at least a pre-configured grant, over a Physical Uplink Shared Channel (PUSCH). In a RACH-less access, the UE has a valid timing advance (“TA”) for the selected LTM or CLTM candidate cell.

[0050] In some embodiments, for both LTM and CLTM, the UE is configured with UE- based TA measurement over one or more LTM candidate cell(s). Using this configuration, the UE can determine whether it can perform UE-based TA measurement for a given LTM candidate cell while being in a certain serving cell or not. In other words, the UE can execute UE-based TA measurement on one or more LTM candidate cell(s) if they belong to the same “TA-measurement group” as the serving cell. An LTM candidate cell can be considered as belonging to the same “TA-estimation group” as the source cell if the value stored in Itm- ServingCellUE-MeasuredTA-ID at the source cell equals the value of Itm-UE-MeasuredTA-ID for the given LTM candidate cell. The UE-based TA measurement on LTM candidate cells can be performed by measuring the difference in the reception timing of the serving cell and the LTM candidate cells that are in the same TA measurement group as the serving cell. The reception timing of a serving cell can be, e.g., the reception timing of a downlink reference signal (e.g., an SSB or a CSLRS) transmitted from the serving cell, and the receive timing of anP111802W001LTM candidate cell can be, e.g., the receive timing of a downlink reference signal transmitted (e.g., an SSB or a CSI-RS) from the LTM cell. The UE may also store the estimated difference between the reception timing of the serving cell and all the LTM candidate cells that are in the same TA measurement group as the serving cell.

[0051] In some embodiments, a UE determines under which conditions to perform a UE- based TA measurement procedure, given that the UE is provided with a UE-based TA measurement configuration for one of more LTM candidate cell(s) and the LTM candidate cell(s) belong to the same TA measurement group as the current serving cell of the UE, before receiving an LTM cell switch command.

[0052] In additional or alternative embodiments, the UE performs TA measurement procedure for an LTM candidate cell as determined by the radio-related measurement quantity (e.g., RSRP, RSRQ, or SINR) of the LTM cell. The radio measurement can be a lower layer or LI measurement quantity (i.e., the measurement is not filtered by a L3 filtering parameter) or can possibly be a L3 measurement quantity (i.e., filtered with L3 filtering parameter) over an LTM candidate cell. Moreover, the radio measurement can be performed over one or more individual beam(s) of the LTM candidate cell and / or the serving cell, or it can be a cell level measurement over the LTM candidate cell and / or the serving cell.

[0053] In some examples, the UE measures the TA value for an LTM candidate cell when the radio measurement for the given LTM candidate cell becomes better than a pre-configured threshold.

[0054] In additional or alternative examples, the UE measures TA value for an LTM candidate cell when the radio measurement for the given LTM candidate cell becomes better than an RSRP value or when it is within an RSRP interval.

[0055] In additional or alternative examples, the UE measures TA value for an LTM candidate cell when the radio measurement for the given LTM candidate cell becomes offset better than the radio measurement of the serving cell.

[0056] In additional or alternative examples, the UE performs TA value measurement when the radio measurement for the serving cell becomes worse than a pre-defined threshold AND the radio measurement for the given LTM candidate cell becomes better than another preconfigured threshold.

[0057] In additional or alternative examples, the UE performs TA value measurement when the radio measurement for the serving cell becomes worse than a pre-defined threshold. In additional or alternative examples, the UE performs TA value measurement either on one LTM candidate cell or on all configured LTM candidate cells. For the latter case, how the UE selects an LTM candidate cell can be according to the radio conditions or according to a specific UEP111802W001 implementation. In additional or alternative examples, the UE does a new (updated) measurement of the TA value for an LTM candidate cell when the radio measurement for that given LTM candidate cell has changed more than an offset compared to when the TA value was measured for that LTM candidate cell the last time. For example, if the UE measures the TA value for an LTM candidate cell (when e.g., a certain RSRP value has been measured for it) and the measured RSRP value for the LTM candidate cell has changed more than an offset value (e.g., that it has become an offset value stronger), the UE triggers a new TA measurement for that LTM candidate cell.

[0058] When the above-mentioned radio link conditions are satisfied for one or more LTM candidate cell(s), it becomes highly likely that the network would send an LTM cell switch command to the UE and the UE would be able to perform a RACH-less LTM execution.

[0059] In additional or alternative embodiments, the UE performs UE -based TA measurement procedure right after receiving the LTM candidate configuration (e.g., after processing the RRC message) and the corresponding UE-based TA measurement configuration for the LTM candidate cells. In some examples, the UE again measures the TA value over the LTM cell (e.g., by performing measurements over the LTM cell SSB or CSLRS) after receiving the LTM cell switch MAC CE, and before updating the value of Itm-ServingCellUE- MeasuredTA-ID and sending the first UL transmission to the new serving cell (which was previously LTM candidate cell or target cell), to ensure the accuracy of the measured TA value.

[0060] In additional or alternative embodiments, the UE performs UE-based TA measurement procedure for a LTM candidate cell indicated in a LTM cell switch MAC CE after receiving the LTM cell switch MAC CE and before sending the first UL transmission to the new serving cell (which was previously LTM candidate cell or target cell).

[0061] In additional or alternative embodiments, the UE performs UE-based TA measurement procedure for a LTM candidate cell when the UE triggers the transmission of an LTM measurement report (e.g., a CSI report including measurement information, e.g., LI RSRP, of one or more CSI resources associated to LTM candidate cell(s)) for the LTM candidate cell (i.e., when that LTM candidate cell becomes a triggered cell). In some examples, the condition which triggers the transmission of an LTM measurement report is the condition which triggers the UE to perform the UE-based TA measurement procedure. An example of such condition may be “beam of an LTM candidate cell becomes an offset (or threshold) better than a beam of the serving cell (e.g., PCell, PSCell, SpCell of MCG, SpCell of SCG)”

[0062] In additional or alternative embodiments, the UE performs the UE-based TA measurement procedure upon detecting a radio link failure and performing LTM fast failureP111802W001 recovery to an LTM candidate cell which shares the similar TA measurement group as the serving cell for attaining a RACH-less LTM.

[0063] In additional or alternative embodiments, the UE performs UE-based TA measurement procedure for an LTM candidate cell when receiving the command to activate a TCI state for this LTM candidate cell.

[0064] In additional or alternative embodiments, the UE performs UE-based TA measurement procedure for an LTM candidate cell when receiving a PDCCH order to trigger the sending of a random-access preamble for this LTM candidate cell.

[0065] In some embodiments, a UE in which the UE determines under which conditions to start to perform UE-based TA measurement procedure, given that the UE is provided UE-based TA measurement configuration for one of more LTM candidate cell(s) and the LTM candidate cell(s) belong to the same TA measurement group as the current serving cell of the UE, before the fulfilment of the CLTM execution conditions and LTM cell switch.

[0066] In additional or alternative embodiments, the UE is configured with at least two conditional LTM execution conditions, denoted as Cl and C2. The conditions Cl and C2 are associated to the reference signals (e.g., SSB or CSLRS) of the LTM candidate cell(s) and / or serving cell, with entering and leaving conditions. In such case, the UE may perform UE-based TA measurement procedure after the one of the CLTM conditions (e.g., Cl or C2) is fulfilled to have a RACH-less cell switch upon the possible fulfilment of the other CLTM execution condition.

[0067] In additional or alternative embodiments, the UE is configured with at least two conditional LTM execution conditions, denoted as Cl and C2. The conditions Cl and C2 are associated to the reference signals (e.g., SSB or CSLRS) of the LTM candidate cell(s) and / or serving cell, with entering and leaving conditions. In such case, the UE may perform UE-based TA measurement procedure after both the CLTM conditions (e.g., Cl and C2) are fulfilled.

[0068] In additional or alternative embodiments, after being configured with LTM candidate cell(s) configuration, CTLM execution condition(s), and UE-based TA measurement configuration for LTM cell(s), the UE may be provided either an SR configuration or a preallocated UL grant via some lower layer dynamic signalling (e.g., MAC CE) for one or more LTM candidate cell(s). Once the UE receives SR configuration or pre-configured UL-grant for LTM candidate cell(s) via lower layer signalling, the UE starts performing the UE-based TA measurement procedure for the LTM candidate cell(s). This way the UE can perform RACH- less CLTM execution once the associated conditions are fulfilled. In some examples, the UE is pre-configured with the UL scheduling grant and / or the SR configuration for the LTM candidate cell but later receives an indication to activate the pre-configured UL resources which serves asP111802W001 a trigger condition for the UE to start performing the UE-based TA measurement procedure for the LTM candidate cell.

[0069] In additional or alternative embodiments, the UE performs UE-based TA measurement procedure right after receiving the LTM candidate configuration (as well as the associated CLTM execution conditions) and the corresponding UE-based TA measurement configuration for the LTM candidate cells. However, after the CLTM execution conditions are fulfilled, the UE again measures the TA value over the LTM cell (e.g., by performing measurements over the LTM cell SSB or CSLRS) before updating the value of Itm- ServingCellUE-MeasuredTA-ID and sending the first UL transmission to the new serving cell (which was previously LTM candidate cell or target cell), for ensuring the accuracy of the measured TA value.

[0070] In additional or alternative embodiments, the UE performs UE-based TA measurement procedure for an LTM candidate cell when receiving the command to activate a TCI state for this LTM candidate cell (network triggers the TCI state activation).

[0071] In additional or alternative embodiments, the UE performs UE-based TA measurement procedure for an LTM candidate cell when determining to activate a TCI state for this LTM candidate cell (UE triggers the TCI state activation on its own).

[0072] In additional or alternative embodiments, the UE performs UE-based TA measurement procedure for an LTM candidate cell when receiving a PDCCH order to trigger the transmission of a random-access preamble for this LTM candidate cell (network triggers the transmission of a random-access preamble to a LTM candidate cell).

[0073] In additional or alternative embodiments, the UE performs UE-based TA measurement procedure for an LTM candidate cell when determining to transmit a randomaccess preamble for this LTM candidate cell (UE triggers the transmission of a random-access preamble to an LTM candidate cell on its own).

[0074] In additional or alternative embodiments, the UE performs UE-based TA measurement procedure for an LTM candidate cell when receiving a random-access response from an LTM candidate cell.

[0075] In additional or alternative embodiments, the UE performs UE-based TA measurement procedure for an LTM candidate cell when receiving an indication which includes a TA value from an LTM candidate cell.

[0076] In additional or alternative embodiments, the UE performs UE-based TA measurement procedure for an LTM candidate cell when receiving an indication which includes a TA value for an LTM candidate cell from the serving cell.P111802W001

[0077] Operations of a communication device QQ200 (implemented using the structure of FIG. 5) will now be discussed with reference to the flow chart of FIG. 3 according to some embodiments of inventive concepts. For example, modules may be stored in memory QQ210 of FIG. 5, and these modules may provide instructions so that when the instructions of a module are executed by respective communication device processing circuitry QQ202, communication device QQ200 performs respective operations of the flow chart.

[0078] FIG. 3 illustrates an example of operations performed by a communication device to perform a TA measurement procedure for a LTM candidate cell in response to a condition being met. In some embodiments, the LTM candidate cell and a serving cell of the communication device both belong to a same TA measurement group. In additional or alternative embodiments, the communication device is configured with one or more conditional LTM, CLTM, execution conditions for the LTM candidate cell.

[0079] At block 310, processing circuitry QQ202 receives, via communication interface QQ212, a communication-device based TA measurement configuration for a LTM candidate cell.

[0080] At block 320, processing circuitry QQ202 determines that a condition has been met prior to receiving a LTM cell switch command. In some embodiments, determining that the condition has been met includes determining that the condition has been met based on a radio measurement of the LTM candidate cell or a serving cell of the communication device.

[0081] In additional or alternative embodiments, determining that the condition has been met includes determining that the communication device received the communication devicebased TA measurement configuration.

[0082] In additional or alternative embodiments, determining that the condition has been met includes determining that a LTM measurement report has been triggered for the LTM candidate cell.

[0083] In additional or alternative embodiments, determining that the condition has been met includes at least one of: detecting a radio link failure; and executing LTM fast failure recover to the LTM candidate cell.

[0084] In additional or alternative embodiments, determining that the condition has been met includes determining that the communication device received a transmission configuration indicator, TCI, state activation command media access control, MAC, control element, CE, for the LTM candidate cell.

[0085] In additional or alternative embodiments, determining that the condition has been met includes determining that the communication device received a physical downlink controlP111802W001 channel, PDCCH, order to transmit physical random access channel, PRACH, preamble for the LTM candidate cell.

[0086] In additional or alternative embodiments, determining that the condition has been met includes determining that at least one of the one or more CLTM execution conditions has been met. In additional or alternative embodiments, determining that the condition has been met includes determining that all of the CLTM execution conditions have been met.

[0087] In additional or alternative embodiments, determining that the condition has been met includes determining that the communication device received a scheduling request, SR, configuration or pre-allocated uplink, UL, grant for the LTM candidate cell.

[0088] In additional or alternative embodiments, determining that the condition has been met includes determining that the communication device received an indication to activate the SR configuration or the pre-allocated uplink, UL, grant for the LTM candidate cell.

[0089] At block 330, processing circuitry QQ202 performs a TA measurement procedure for the LTM candidate cell. In some embodiments, performing the TA measurement procedure includes performing the TA measurement procedure prior to receiving an LTM cell switch command.

[0090] At block 340, processing circuitry QQ202 performs the TA measurement procedure again. In some embodiments, performing the TA measurement procedure again includes performing the TA measurement procedure again after receiving a LTM switch command for the LTM candidate cell and prior to transmitting an UL signal to the LTM candidate cell.

[0091] In additional or alternative embodiments, performing the TA measurement procedure again includes performing the TA measurement procedure again after the one or more CLTM execution conditions are met and prior to transmitting the UL signal to the LTM candidate cell.

[0092] Various operations from the flow chart of FIG. 3 may be optional with respect to some embodiments of communication devices and related methods.

[0093] Example Embodiments are provided below.

[0094] Embodiment 1. A method at a User Equipment (UE) wherein: performing a UE- based TA measurement procedure for an LTM candidate cell when the UE is provided UE- based TA measurement configuration for that LTM candidate cell.

[0095] Embodiment 2. The method of Embodiment 1, wherein the LTM candidate cell belongs to the same TA measurement group as the serving cell.

[0096] Embodiment 3. The method of any of Embodiments 1-2, wherein the UE-based TA measurement procedure for the LTM candidate cell is triggered by the fulfillment of one or more conditions.P111802W001

[0097] Embodiment 4. The method of any of Embodiments 1-3, wherein the one or more conditions to start measuring the UE-based TA value are dependent upon the radio measurements of the LTM candidate cell and / or the serving cell.

[0098] Embodiment 5. The method of any of Embodiments 1-4, wherein the radio measurements which define the one or more conditions to start measuring the UE-based TA value are either lower layer measurements or L3 -measurements.

[0099] Embodiment 6. The method of any of Embodiments 1-2, wherein the UE performs UE-based TA measurement right after receiving the LTM candidate cell configuration.

[0100] Embodiment 7. The method of any of Embodiments 1-2 and 6, wherein the UE repeats the UE-based TA measurement procedure after receiving the LTM cell switch command for an LTM candidate cell, and before updating the Itm-ServingCellUE-MeasuredTA-ID and sending the first UL transmission to that LTM cell.

[0101] Embodiment 8. The method of Embodiments 1-2, wherein the UE performs UE- based TA measurement for an LTM candidate cell upon triggering the LTM measurement report for that LTM candidate cell.

[0102] Embodiment 9. The method of any of Embodiments 1-2 and 8, wherein the one or more conditions for the UE-based TA measurement and the triggering of LTM measurement report are similar.

[0103] Embodiment 10. The method of any of Embodiments 1-2, wherein the UE performs UE-based TA measurement for an LTM candidate cell upon detecting a radio link failure and executing LTM fast failure recovery to that LTM candidate cell.

[0104] Embodiment 11. The method of any of Embodiments 1-2, wherein the UE performs UE-based TA measurement for an LTM candidate cell upon receiving TCI state activation command MAC CE for that LTM candidate cell.

[0105] Embodiment 12. The method of any of Embodiments 1-2, wherein the UE performs UE-based TA measurement for an LTM candidate cell upon receiving the PDCCH order to transmit PRACH preamble for that LTM candidate cell.

[0106] Embodiment 13. The method of any of Embodiments 1-2, wherein the UE is configured with one or two conditional LTM (CLTM) execution conditions for an LTM candidate cell.

[0107] Embodiment 14. The method of any of Embodiments 1-2 and 13, wherein the UE is configured with two CLTM execution conditions for an LTM candidate cell and performs UE- based TA measurement for that LTM candidate cell upon fulfilment of one of the CLTM execution conditions.P111802W001

[0108] Embodiment 15. The method of any of Embodiments 1-2 and 13-14, wherein the UE performs UE-based TA measurement for an LTM candidate cell upon fulfilment of both CLTM execution conditions for that LTM candidate cell.

[0109] Embodiment 16. The method of any of Embodiments 1-2 and 13, wherein the UE performs UE-based TA measurement for an LTM candidate cell upon receiving the SR configuration or pre-allocated UL grant for that LTM candidate cell.

[0110] Embodiment 17. The method of any of Embodiments 1-2, 13, and 16, wherein the UE performs UE-based TA measurement for an LTM candidate cell upon receiving an indication to activate the pre-configured UL grant or SR configuration for that LTM candidate cell.

[0111] Embodiment 19. The method of any of Embodiments 1-2 and 13, wherein the UE performs UE-based TA measurement right after receiving the LTM candidate cell configuration, and then repeats the UE-based TA measurement procedure after the CLTM execution condition(s) is fulfilled, before updating the Itm-ServingCellUE-MeasuredTA-ID and sending the first UL transmission to that LTM cell.

[0112] Embodiment 20. The method of any of Embodiments 1-2 and 13, wherein the method defined in Embodiment 9 is also applicable to conditional LTM functionality at the UE.

[0113] Embodiment 21. The method of any of Embodiments 1-2 and 13, wherein the UE performs UE-based TA measurement for an LTM candidate cell upon determining to activate the TCI state for that LTM candidate cell.

[0114] Embodiment 22. The method of any of Embodiments 1-2 and 13, wherein the method defined in A10 is also applicable to conditional LTM functionality at the UE.

[0115] Embodiment 23. The method of any of Embodiments 1-2 and 13, wherein the UE performs UE-based TA measurement for an LTM candidate cell upon determining to send a PRACH preamble to that LTM candidate cell.

[0116] Embodiment 24. The method of any of Embodiments 1-2 and 13, wherein the UE performs UE-based TA measurement for an LTM candidate cell upon receiving the randomaccess response from that LTM candidate cell.

[0117] Embodiment 25. The method of any of Embodiments 1-2 and 13, wherein the UE performs UE-based TA measurement for an LTM candidate cell upon receiving an indication from that LTM candidate cell, including the LTM candidate cell TA value.

[0118] Embodiment 26. The method of any of Embodiments 1-2 and 13, wherein the UE performs UE-based TA measurement for an LTM candidate cell upon receiving an indication from the source cell, including the TA value for that LTM candidate cell.P111802W001

[0119] FIG. 4 shows an example of a communication system QQ 100 in accordance with some embodiments.

[0120] In the example, the communication system QQ100 includes a telecommunication network QQ102 that includes an access network QQ104, such as a radio access network (RAN), and a core network QQ106, which includes one or more core network nodes QQ108. The access network QQ104 includes one or more access network nodes, such as network nodes QQ110a and QQl lOb (one or more of which may be generally referred to as network nodes QQ110), or any other similar 3rdGeneration Partnership Project (3GPP) access nodes or non-3GPP access points. Moreover, as will be appreciated by those of skill in the art, a network node is not necessarily limited to an implementation in which a radio portion and a baseband portion are supplied and integrated by a single vendor. Thus, it will be understood that network nodes include disaggregated implementations or portions thereof. For example, in some embodiments, the telecommunication network QQ102 includes one or more Open-RAN (ORAN) network nodes. An ORAN network node is a node in the telecommunication network QQ102 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 QQ102, including one or more network nodes QQ110 and / or core network nodes QQ108.

[0121] 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 QQ110 facilitate direct or indirect connection of user equipment (UE), such as by connecting UEs QQ112a, QQ112b, QQ112c, and QQ112d (one or more of which may be generally referred to as UEs QQ112) to the core network QQ106 over one or more wireless connections.P111802W001

[0122] 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 QQ100 may include any number of wired or wireless networks, network nodes, UEs, and / or any other components or systems that may facilitate or participate in the communication of data and / or signals whether via wired or wireless connections. The communication system QQ100 may include and / or interface with any type of communication, telecommunication, data, cellular, radio network, and / or other similar type of system.

[0123] The UEs QQ112 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 QQ110 and other communication devices. Similarly, the network nodes QQ110 are arranged, capable, configured, and / or operable to communicate directly or indirectly with the UEs QQ112 and / or with other network nodes or equipment in the telecommunication network QQ102 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 QQ102.

[0124] In the depicted example, the core network QQ106 connects the network nodes QQ110 to one or more host computing systems, such as host QQ116. 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 QQ106 includes one more core network nodes (e.g., core network node QQ108) 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 QQ108. 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).

[0125] The host QQ116 may be under the ownership or control of a service provider other than an operator or provider of the access network QQ104 and / or the telecommunication network QQ102. The host QQ116 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 aP111802W001 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.

[0126] As a whole, the communication system QQ100 of FIG. 4 enables connectivity between the UEs, network nodes, and hosts. In that sense, the communication system may be configured to operate according to predefined rules or procedures, such as specific standards that include, but are not limited to: Global System for Mobile Communications (GSM); Universal Mobile Telecommunications System (UMTS); Long Term Evolution (LTE), and / or other suitable 2G, 3G, 4G, 5G standards, or any applicable future generation standard (e.g., 6G); wireless local area network (WLAN) standards, such as the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standards (WiFi); and / or any other appropriate wireless communication standard, such as the Worldwide Interoperability for Microwave Access (WiMax), Bluetooth, Z-Wave, Near Field Communication (NFC) ZigBee, LiFi, and / or any low-power wide-area network (LPWAN) standards such as LoRa and Sigfox.

[0127] In some examples, the telecommunication network QQ102 is a cellular network that implements 3GPP standardized features. Accordingly, the telecommunications network QQ102 may support network slicing to provide different logical networks to different devices that are connected to the telecommunication network QQ102. For example, the telecommunications network QQ102 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.

[0128] In some examples, the UEs QQ112 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 QQ104 on a predetermined schedule, when triggered by an internal or external event, or in response to requests from the access network QQ104. 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).

[0129] In the example, the hub QQ114 communicates with the access network QQ104 to facilitate indirect communication between one or more UEs (e.g., UE QQ112c and / or QQ112d) and network nodes (e.g., network node QQl lOb). In some examples, the hub QQ114 may be a controller, router, content source and analytics, or any of the other communication devices described herein regarding UEs. For example, the hub QQ114 may be a broadband router enabling access to the core network QQ106 for the UEs. As another example, the hub QQ114 may be aP111802W001 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 QQ110, or by executable code, script, process, or other instructions in the hub QQ114. As another example, the hub QQ114 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 QQ114 may be a content source. For example, for a UE that is a VR device, display, loudspeaker, or other media delivery device, the hub QQ114 may retrieve VR assets, video, audio, or other media or data related to sensory information via a network node, which the hub QQ114 then provides to the UE either directly, after performing local processing, and / or after adding additional local content. In still another example, the hub QQ114 acts as a proxy server or orchestrator for the UEs, in particular if one or more of the UEs are low energy loT devices.

[0130] The hub QQ114 may have a constant / persistent or intermittent connection to the network node QQl lOb. The hub QQ114 may also allow for a different communication scheme and / or schedule between the hub QQ114 and UEs (e.g., UE QQ112c and / or QQ112d), and between the hub QQ114 and the core network QQ106. In other examples, the hub QQ114 is connected to the core network QQ106 and / or one or more UEs via a wired connection. Moreover, the hub QQ114 may be configured to connect to an M2M service provider over the access network QQ104 and / or to another UE over a direct connection. In some scenarios, UEs may establish a wireless connection with the network nodes QQ110 while still connected via the hub QQ114 via a wired or wireless connection. In some embodiments, the hub QQ114 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 QQ110b. In other embodiments, the hub QQ114 may be a non-dedicated hub - that is, a device which is capable of operating to route communications between the UEs and network node QQ110b, but which is additionally capable of operating as a communication start and / or end point for certain data channels.

[0131] FIG. 5 shows a UE QQ200 in accordance with some embodiments. The UE QQ200 presents additional details of some embodiments of the UE QQ112 of Figure 1. 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 examplesP111802W001 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.

[0132] 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), orvehicle-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).

[0133] The UE QQ200 includes processing circuitry QQ202 that is operatively coupled via a bus QQ204 to an input / output interface QQ206, a power source QQ208, a memory QQ210, a communication interface QQ212, and / or any other component, or any combination thereof. Certain UEs may utilize all or a subset of the components shown in FIG. 5. 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.

[0134] The processing circuitry QQ202 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 QQ210. The processing circuitry QQ202 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 QQ202 may include multiple central processing units (CPUs).

[0135] In the example, the input / output interface QQ206 may be configured to provide an interface or interfaces to an input device, output device, or one or more input and / or output devices. Examples of an output device include a speaker, a sound card, a video card, a display, a monitor, a printer, an actuator, an emitter, a smartcard, another output device, or any combination thereof. An input device may allow a user to capture information into the UE QQ200. Examples of an input device include a touch-sensitive or presence-sensitive display, a camera (e.g., a digitalP111802W001 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.

[0136] In some embodiments, the power source QQ208 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 QQ208 may further include power circuitry for delivering power from the power source QQ208 itself, and / or an external power source, to the various parts of the UE QQ200 via input circuitry or an interface such as an electrical power cable. Delivering power may be, for example, for charging of the power source QQ208. Power circuitry may perform any formatting, converting, or other modification to the power from the power source QQ208 to make the power suitable for the respective components of the UE QQ200 to which power is supplied.

[0137] The memory QQ210 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 readonly memory (EEPROM), magnetic disks, optical disks, hard disks, removable cartridges, flash drives, and so forth. In one example, the memory QQ210 includes one or more application programs QQ214, such as an operating system, web browser application, a widget, gadget engine, or other application, and corresponding data QQ216. The memory QQ210 may store, for use by the UE QQ200, any of a variety of various operating systems or combinations of operating systems.

[0138] The memory QQ210 may be configured to include a number of physical drive units, such as redundant array of independent disks (RAID), flash memory, USB flash drive, external hard disk drive, thumb drive, pen drive, key drive, high-density digital versatile disc (HD-DVD) optical disc drive, internal hard disk drive, Blu-Ray optical disc drive, holographic digital data storage (HDDS) optical disc drive, external mini-dual in-line memory module (DIMM), synchronous dynamic random access memory (SDRAM), external micro-DIMM SDRAM, smartcard memory such as tamper resistant module in the form of a universal integrated circuit card (UICC) including one or more subscriber identity modules (SIMs), such as a USIM and / or ISIM, other memory, or any combination thereof. The UICC may for example be an embedded UICC (eUICC), integrated UICC (iUICC) or a removable UICC commonly known as ‘SIM card.’P111802W001The memory QQ210 may allow the UE QQ200 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 QQ210, which may be or comprise a device-readable storage medium.

[0139] The processing circuitry QQ202 may be configured to communicate with an access network or other network using the communication interface QQ212. The communication interface QQ212 may comprise one or more communication subsystems and may include or be communicatively coupled to an antenna QQ222. The communication interface QQ212 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 QQ218 and / or a receiver QQ220 appropriate to provide network communications (e.g., optical, electrical, frequency allocations, and so forth). Moreover, the transmitter QQ218 and receiver QQ220 may be coupled to one or more antennas (e.g., antenna QQ222) and may share circuit components, software or firmware, or alternatively be implemented separately.

[0140] In the illustrated embodiment, communication functions of the communication interface QQ212 may include cellular communication, Wi-Fi communication, LPWAN communication, data communication, voice communication, multimedia communication, short- range communications such as Bluetooth, near-field communication, location-based communication such as the use of the global positioning system (GPS) to determine a location, another like communication function, or any combination thereof. Communications may be implemented in according to one or more communication protocols and / or standards, such as IEEE 802.11, Code Division Multiplexing Access (CDMA), Wideband Code Division Multiple Access (WCDMA), GSM, LTE, New Radio (NR), UMTS, WiMax, Ethernet, transmission control protocol / internet protocol (TCP / IP), synchronous optical networking (SONET), Asynchronous Transfer Mode (ATM), QUIC, Hypertext Transfer Protocol (HTTP), and so forth.

[0141] Regardless of the type of sensor, a UE may provide an output of data captured by its sensors, through its communication interface QQ212, 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).P111802W001

[0142] 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.

[0143] 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 QQ200 shown in FIG. 5.

[0144] 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 of such monitoring and / or measurements to another UE and / or a network node. The UE may in this case be an M2M device, which may in a 3GPP context be referred to as an MTC device. As one particular example, the UE may implement the 3GPP NB-IoT standard. In other scenarios, a UE may represent a vehicle, such as a car, a bus, a truck, a ship and an airplane, or other equipment that is capable of monitoring and / or reporting on its operational status or other functions associated with its operation.

[0145] 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 describedP111802W001 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.

[0146] FIG. 6 shows a network node QQ300 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).

[0147] 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).

[0148] Other examples of network nodes include multiple transmission point (multi-TRP) 5G access nodes, multi -standard radio (MSR) equipment such as MSR BSs, network controllers such as radio network controllers (RNCs) or base station controllers (BSCs), base transceiver stations (BTSs), transmission points, transmission nodes, multi-cell / multicast coordination entities (MCEs), Operation and Maintenance (O&M) nodes, Operations Support System (OSS) nodes, Self-Organizing Network (SON) nodes, positioning nodes (e.g., Evolved Serving Mobile Location Centers (E-SMLCs)), and / or Minimization of Drive Tests (MDTs).

[0149] The network node QQ300 includes a processing circuitry QQ302, a memory QQ304, a communication interface QQ306, and a power source QQ308. The network node QQ300 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 QQ300 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 QQ300 may be configured to support multiple radio access technologies (RATs). In such embodiments, someP111802W001 components may be duplicated (e.g., separate memory QQ304 for different RATs) and some components may be reused (e.g., a same antenna QQ310 may be shared by different RATs). The network node QQ300 may also include multiple sets of the various illustrated components for different wireless technologies integrated into network node QQ300, 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 QQ300.

[0150] The processing circuitry QQ302 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 QQ300 components, such as the memory QQ304, to provide network node QQ300 functionality.

[0151] In some embodiments, the processing circuitry QQ302 includes a system on a chip (SOC). In some embodiments, the processing circuitry QQ302 includes one or more of radio frequency (RF) transceiver circuitry QQ312 and baseband processing circuitry QQ314. In some embodiments, the radio frequency (RF) transceiver circuitry QQ312 and the baseband processing circuitry QQ314 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 QQ312 and baseband processing circuitry QQ314 may be on the same chip or set of chips, boards, or units.

[0152] The memory QQ304 may comprise any form of volatile or non-volatile computer- readable memory including, without limitation, persistent storage, solid-state memory, remotely mounted memory, magnetic media, optical media, random access memory (RAM), read-only memory (ROM), mass storage media (for example, a hard disk), removable storage media (for example, a flash drive, a Compact Disk (CD) or a Digital Video Disk (DVD)), and / or any other volatile or non-volatile, non-transitory device-readable and / or computer-executable memory devices that store information, data, and / or instructions that may be used by the processing circuitry QQ302. The memory QQ304 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 QQ302 and utilized by the network node QQ300. The memory QQ304 may be used to store any calculations made by the processing circuitry QQ302 and / or any data received via the communication interface QQ306. In some embodiments, the processing circuitry QQ302 and memory QQ304 is integrated.P111802W001

[0153] The communication interface QQ306 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 QQ306 comprises port(s) / terminal(s) QQ316 to send and receive data, for example to and from a network over a wired connection. The communication interface QQ306 also includes radio front-end circuitry QQ318 that may be coupled to, or in certain embodiments a part of, the antenna QQ310. Radio front-end circuitry QQ318 comprises filters QQ320 and amplifiers QQ322. The radio front-end circuitry QQ318 may be connected to an antenna QQ310 and processing circuitry QQ302. The radio front-end circuitry may be configured to condition signals communicated between antenna QQ310 and processing circuitry QQ302. The radio frontend circuitry QQ318 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 QQ318 may convert the digital data into a radio signal having the appropriate channel and bandwidth parameters using a combination of filters QQ320 and / or amplifiers QQ322. The radio signal may then be transmitted via the antenna QQ310. Similarly, when receiving data, the antenna QQ310 may collect radio signals which are then converted into digital data by the radio front-end circuitry QQ318. The digital data may be passed to the processing circuitry QQ302. In other embodiments, the communication interface may comprise different components and / or different combinations of components.

[0154] In certain alternative embodiments, the network node QQ300 does not include separate radio front-end circuitry QQ318, instead, the processing circuitry QQ302 includes radio front-end circuitry and is connected to the antenna QQ310. Similarly, in some embodiments, all or some of the RF transceiver circuitry QQ312 is part of the communication interface QQ306. In still other embodiments, the communication interface QQ306 includes one or more ports or terminals QQ316, the radio front-end circuitry QQ318, and the RF transceiver circuitry QQ312, as part of a radio unit (not shown), and the communication interface QQ306 communicates with the baseband processing circuitry QQ314, which is part of a digital unit (not shown).

[0155] The antenna QQ310 may include one or more antennas, or antenna arrays, configured to send and / or receive wireless signals. The antenna QQ310 may be coupled to the radio frontend circuitry QQ318 and may be any type of antenna capable of transmitting and receiving data and / or signals wirelessly. In certain embodiments, the antenna QQ310 is separate from the network node QQ300 and connectable to the network node QQ300 through an interface or port.

[0156] The antenna QQ310, communication interface QQ306, and / or the processing circuitryQQ302 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 QQ310, the communication interface QQ306, and / or the processing circuitry QQ302P111802W001 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.

[0157] The power source QQ308 provides power to the various components of network node QQ300 in a form suitable for the respective components (e.g., at a voltage and current level needed for each respective component). The power source QQ308 may further comprise, or be coupled to, power management circuitry to supply the components of the network node QQ300 with power for performing the functionality described herein. For example, the network node QQ300 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 QQ308. As a further example, the power source QQ308 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.

[0158] Embodiments of the network node QQ300 may include additional components beyond those shown in FIG. 6 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 QQ300 may include user interface equipment to allow input of information into the network node QQ300 and to allow output of information from the network node QQ300. This may allow a user to perform diagnostic, maintenance, repair, and other administrative functions for the network node QQ300. In some embodiments providing a core network node, such as core network node 108 of FIG. 4, some components, such as the radio front-end circuitry QQ318 and the RF transceiver circuitry QQ312 may be omitted.

[0159] FIG. 7 is a block diagram illustrating a virtualization environment QQ400 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 QQ400 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),P111802W001 then the node may be entirely virtualized. In some embodiments, the virtualization environment QQ400 includes components defined by the O-RAN Alliance, such as an O-Cloud environment orchestrated by a Service Management and Orchestration Framework via an 0-2 interface. Virtualization may facilitate distributed implementations of a network node, UE, core network node, or host.

[0160] Applications QQ402 (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.

[0161] Hardware QQ404 includes processing circuitry, memory that stores software and / or instructions executable by hardware processing circuitry, and / or other hardware devices as described herein, such as a network interface, input / output interface, and so forth. Software may be executed by the processing circuitry to instantiate one or more virtualization layers QQ406 (also referred to as hypervisors or virtual machine monitors (VMMs)), provide VMs QQ408a and QQ408b (one or more of which may be generally referred to as VMs QQ408), and / or perform any of the functions, features and / or benefits described in relation with some embodiments described herein. The virtualization layer QQ406 may present a virtual operating platform that appears like networking hardware to the VMs QQ408.

[0162] The VMs QQ408 comprise virtual processing, virtual memory, virtual networking or interface and virtual storage, and may be run by a corresponding virtualization layer QQ406. Different embodiments of the instance of a virtual appliance QQ402 may be implemented on one or more of VMs QQ408, 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.

[0163] In the context of NFV, a VM QQ408 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 QQ408, and that part of hardware QQ404 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 QQ408 on top of the hardware QQ404 and corresponds to the application QQ402.

[0164] Hardware QQ404 may be implemented in a standalone network node with generic or specific components. Hardware QQ404 may implement some functions via virtualization.P111802W001Alternatively, hardware QQ404 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 QQ410, which, among others, oversees lifecycle management of applications QQ402. In some embodiments, hardware QQ404 is coupled to one or more radio units that each include one or more transmitters and one or more receivers that may be coupled to one or more antennas. Radio units may communicate directly with other hardware nodes via one or more appropriate network interfaces and may be used in combination with the virtual components to provide a virtual node with radio capabilities, such as a radio access node or a base station. In some embodiments, some signaling can be provided with the use of a control system QQ412 which may alternatively be used for communication between hardware nodes and radio units.

[0165] 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.

[0166] 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 particularP111802W001 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.P111802W001EMBODIMENTS1. A method of operating a communication device, the method comprising: determining (320) that a condition has been met; and responsive to determining that the condition has been met, performing (330) a timing advance, TA, measurement procedure for a layer l / layer2 -triggered mobility, LTM, candidate cell.2. The method of Embodiment 2, wherein the LTM candidate cell and a serving cell of the communication device both belong to a same TA measurement group.3. The method of any of Embodiments 1-2, wherein performing the TA measurement procedure comprises performing the TA measurement procedure prior to receiving an LTM cell switch command.4. The method of any of Embodiments 1-3, wherein determining that the condition has been met comprises determining that the condition has been met based on a radio measurement of the LTM candidate cell or a serving cell of the communication device.5. The method of any of Embodiments 1-4, further comprising: receiving (310) a communication device-based TA measurement configuration for the LTM candidate cell.6. The method of Embodiment 5, wherein determining that the condition has been met comprises determining that the communication device received the communication device-based TA measurement configuration.7. The method of Embodiment 6, further comprising: performing (340) the TA measurement procedure again after receiving a LTM switch command for the LTM candidate cell and prior to transmitting an UL signal to the LTM candidate cell.8. The method of any of Embodiments 1-7, wherein determining that the condition has been met comprises determining that a LTM measurement report has been triggered for the LTM candidate cell.P111802W0019. The method of any of Embodiments 1-8, wherein determining that the condition has been met comprises at least one of: detecting a radio link failure; and executing LTM fast failure recover to the LTM candidate cell.10. The method of any of Embodiments 1-9, wherein determining that the condition has been met comprises determining that the communication device received a transmission configuration indicator, TCI, state activation command media access control, MAC, control element, CE, for the LTM candidate cell.11. The method of any of Embodiments 1-10, wherein determining that the condition has been met comprises determining that the communication device received a physical downlink control channel, PDCCH, order to transmit physical random access channel, PRACH, preamble for the LTM candidate cell.12. The method of any of Embodiments 1-11, wherein determining that the condition has been met comprises determining that the communication device has transmitted a PRACH preamble to the LTM candidate cell.13. The method of any of Embodiments 1-12, wherein the communication device is configured with one or more conditional LTM, CLTM, execution conditions for the LTM candidate cell.14. The method of Embodiment 13, wherein determining that the condition has been met comprises determining that at least one of the one or more CLTM execution conditions has been met.15. The method of any of Embodiments 13-14, wherein determining that the condition has been met comprises determining that all of the CLTM execution conditions have been met.16. The method of any of Embodiments 1-15, wherein determining that the condition has been met comprises determining that the communication device received a scheduling request, SR, configuration or pre-allocated uplink, UL, grant for the LTM candidate cell.P111802W00117. The method of Embodiment 16, wherein determining that the condition has been met comprises determining that the communication device received an indication to activate the SR configuration or the pre-allocated uplink, UL, grant for the LTM candidate cell.18. The method of Embodiment 17, further comprising: performing (340) the TA measurement procedure again after the one or more CLTM execution conditions are met and prior to transmitting the UL signal to the LTM candidate cell.19. A communication device (QQ200) adapted to perform operations comprising: determining (320) that a condition has been met; and responsive to determining that the condition has been met, performing (330) a timing advance, TA, measurement procedure for a layer l / layer2 -triggered mobility, LTM candidate cell.20. The communication device of Embodiment 19, the operations further comprising any of the operations of Embodiments 2-18.21. A computer program comprising program code to be executed by processing circuitry (QQ202) of a communication device (QQ200), whereby execution of the program code causes the communication device to perform operations comprising: determining (320) that a condition has been met; and responsive to determining that the condition has been met, performing (330) a timing advance, TA, measurement procedure for a layer l / layer2 -triggered mobility, LTM candidate cell.22. The computer program of Embodiment 21, the operations further comprising any of the operations of Embodiments 2-18.23. A computer program product comprising a non-transitory storage medium (QQ210) including program code to be executed by processing circuitry (QQ202) of a communication device (QQ200), whereby execution of the program code causes the communication device to perform operations comprising: determining (320) that a condition has been met; and responsive to determining that the condition has been met, performing (330) a timing advance, TA, measurement procedure for a layer l / layer2 -triggered mobility, LTM candidateP111802W001 cell.24. The computer program product of Embodiment 23, further comprising any of the operations of Embodiments 2-18.

Claims

P111802W001CLAIMS1. A method of operating a communication device, wherein a LTM candidate cell and a serving cell of the communication device belong to a same TA measurement group, the method comprising: determining (320) that a condition has been met; and responsive to determining that the condition has been met, performing (330) a timing advance, TA, measurement procedure for a layer l / layer2 -triggered mobility, LTM, candidate cell prior to receiving a LTM cell switch command.

2. The method of Claim 1, wherein determining that the condition has been met comprises determining that the condition has been met based on a radio measurement of the LTM candidate cell or a serving cell of the communication device.

3. The method of any of Claims 1-2, further comprising: receiving (310) a communication device-based TA measurement configuration for the LTM candidate cell.

4. The method of Claim 3, wherein determining that the condition has been met comprises determining that the communication device received the communication device-based TA measurement configuration.

5. The method of Claim 4, further comprising: performing (340) the TA measurement procedure again after receiving a LTM switch command for the LTM candidate cell and prior to transmitting an UL signal to the LTM candidate cell.

6. The method of any of Claims 1-5, wherein determining that the condition has been met comprises determining that a LTM measurement report has been triggered for the LTM candidate cell.

7. The method of any of Claims 1-6, wherein determining that the condition has been met comprises at least one of: detecting a radio link failure; and executing LTM fast failure recover to the LTM candidate cell.P111802W0018. The method of any of Claims 1-7, wherein determining that the condition has been met comprises determining that the communication device received a transmission configuration indicator, TCI, state activation command media access control, MAC, control element, CE, for the LTM candidate cell.

9. The method of any of Claims 1-8, wherein determining that the condition has been met comprises determining that the communication device received a physical downlink control channel, PDCCH, order to transmit physical random access channel, PRACH, preamble for the LTM candidate cell.

10. The method of any of Claims 1-9, wherein determining that the condition has been met comprises determining that the communication device has transmitted a PRACH preamble to the LTM candidate cell.

11. The method of any of Claims 1-10, wherein the communication device is configured with one or more conditional LTM, CLTM, execution conditions for the LTM candidate cell.

12. The method of Claim 11, wherein determining that the condition has been met comprises determining that at least one of the one or more CLTM execution conditions has been met.

13. The method of any of Claims 11-12, wherein determining that the condition has been met comprises determining that all of the CLTM execution conditions have been met.

14. The method of any of Claims 1-13, wherein determining that the condition has been met comprises determining that the communication device received a scheduling request, SR, configuration or pre-allocated uplink, UL, grant for the LTM candidate cell.

15. The method of Claim 14, wherein determining that the condition has been met comprises determining that the communication device received an indication to activate the SR configuration or the pre-allocated uplink, UL, grant for the LTM candidate cell.

16. The method of Claim 15, further comprising: performing (340) the TA measurement procedure again after the one or more CLTM execution conditions are met and prior to transmitting the UL signal to the LTM candidate cell.P111802W00117. A communication device (QQ200), wherein the communication device is configurable to with the LTM candidate cell and a serving cell belonging to a same TA measurement group, adapted to perform operations comprising: determining (320) that a condition has been met; and responsive to determining that the condition has been met, performing (330) a timing advance, TA, measurement procedure for a layer l / layer2 -triggered mobility, LTM candidate cell prior to receiving a LTM cell switch command.

18. The communication device of Claim 17, the operations further comprising any of the operations of Claims 1-16.

19. A computer program comprising program code to be executed by processing circuitry (QQ202) of a communication device (QQ200), wherein the communication device is configurable to with the LTM candidate cell and a serving cell belonging to a same TA measurement group, whereby execution of the program code causes the communication device to perform operations comprising: determining (320) that a condition has been met; and responsive to determining that the condition has been met, performing (330) a timing advance, TA, measurement procedure for a layer l / layer2 -triggered mobility, LTM candidate cell prior to receiving a LTM cell switch command.

20. The computer program of Claim 19, the operations further comprising any of the operations of Claims 1-16.

21. A computer program product comprising a non-transitory storage medium (QQ210) including program code to be executed by processing circuitry (QQ202) of a communication device (QQ200), wherein the communication device is configurable to with the LTM candidate cell and a serving cell belonging to a same TA measurement group, whereby execution of the program code causes the communication device to perform operations comprising: determining (320) that a condition has been met; and responsive to determining that the condition has been met, performing (330) a timing advance, TA, measurement procedure for a layer l / layer2 -triggered mobility, LTM candidate cell prior to receiving a LTM cell switch command.P111802W00122. The computer program product of Claim 21, further comprising any of the operations of Claims 1-16.

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