Conditional handover

Abstract

The present disclosure relates to conditional handover. Example embodiments of the present disclosure describe a user equipment, UE, a UE access stratum, UE-AS, a radio access network node, RAN, a method and / or a computer program for handover between a source node and a target node of a mobile communication system, comprising: receiving, at a UE-AS layer of the mobile communication system, a reconfiguration message from a first RAN node serving the UE, the reconfiguration message comprising a conditional handover, CHO, configuration, the CHO configuration comprising one or more quality of experience, QoE, execution conditions for one or more target cells associated with one or more target network nodes; sending a request to a UE application layer, UE APP layer, to verify whether the QoE execution conditions for one or more of the target cells are fulfilled; receiving a response from the UE APP layer, the response indicating whether the QoE conditions for one or more of the target cells are fulfilled; and initiating a handover to the target cell in case at least the QoE execution conditions are fulfilled by the target cell.

Description

Technical Field

[0001] Example embodiments may relate to user equipment, user equipment access layer, radio access network node, method and / or computer program for handover between source node and target node in a mobile communication system. Background Technology

[0002] Handover algorithms have been developed to assist in transferring a UE from a cell associated with a source radio access network (RAN) node to one of multiple target cells associated with one or more target RAN nodes, when a specific target cell offers better communication options based on certain metrics. In some conditional handover (CHO) algorithms, defined CHO conditions can be evaluated at the UE, and handover can be triggered under the UE's control. Summary of the Invention

[0003] The scope of protection sought by the various embodiments of this disclosure is defined by the independent claims. Embodiments and features (if any) described in this specification that are not within the scope of the independent claims are to be interpreted as examples useful for understanding the various embodiments of this disclosure.

[0004] In a first aspect, this specification describes a user equipment (UE) of a mobile communication system, the UE comprising: components (e.g., a radio input) for receiving a reconfiguration message (e.g., an RRC reconfiguration message) from a first radio access network (RAN) node (e.g., a source RAN node) serving the UE, the reconfiguration message including a conditional handover (CHO) configuration, the CHO configuration including one or more quality of experience (QoE) execution conditions for one or more target cells associated with one or more target RAN nodes; and components (e.g., a control module) for determining whether to trigger a handover from a cell associated with the first RAN node to one of the one or more target cells based at least in part on whether the QoE execution conditions for the corresponding target cell in the CHO configuration are met.

[0005] Whether the QoE execution conditions for the corresponding target cell are met can be determined based on the QoE measurements obtained by the UE's application layer (UE APP layer).

[0006] The UE may also include components (e.g., a processor) for generating QoE measurement reports. The UE may also include components (e.g., a radio output) for providing QoE measurement reports to the first RAN node.

[0007] The QoE execution conditions defined in the CHO configuration can be based on QoE measurements generated by other UEs operating with one or more target cells.

[0008] The CHO configuration includes one or more radio execution conditions for one or more target cells associated with one or more target RAN nodes. The UE may also include a component (e.g., a control module) for determining whether to trigger a handover from the cell associated with the first RAN node to one of the one or more target cells based on whether the radio execution conditions included in the CHO configuration are satisfied by the corresponding target cell.

[0009] In a second aspect, this specification describes a first radio access network (RAN) node (e.g., a source RAN node) of a mobile communication system, the first RAN node comprising: components (e.g., radio output) for sending a conditional handover (CHO) request to one or more target RAN nodes and configuring resources for the CHO for a user equipment (UE) served by the first RAN node; components (e.g., radio input) for receiving a CHO request acknowledgment from one or more target RAN nodes in response to the CHO request, wherein each CHO request acknowledgment includes a CHO configuration, the CHO configuration including information related to the QoE experienced by one or more UEs served by the respective target RAN node; components (e.g., a control module) for determining CHO conditions for one or more target cells associated with one or more target RAN nodes; and components (e.g., radio output) for providing a reconfiguration message (e.g., an RRC reconfiguration message) to the UE, wherein the reconfiguration message includes a conditional handover CHO configuration, the CHO configuration including one or more QoE execution conditions for one or more target cells associated with one or more target RAN nodes. The CHO configuration includes one or more radio execution conditions for one or more target cells associated with one or more target RAN nodes.

[0010] The first RAN node may further include components (e.g., radio output) for sending a QoE measurement configuration request to the UE, wherein the QoE measurement configuration request is within an RRC reconfiguration message. The first RAN node may also include components (e.g., radio input) for receiving a QoE measurement report from the UE in response to the QoE measurement configuration request.

[0011] The first RAN node may also include components (e.g., radio inputs) for receiving radio measurements from the UE, and may also include components (e.g., a processor) for making CHO configuration decisions based at least in part on the received radio messages.

[0012] In some example embodiments, information related to the QoE experienced at one or more UEs served by the respective target RAN node includes QoE measurements for one or more QoE metrics.

[0013] In some example embodiments, information related to the QoE experienced at one or more UEs served by the respective target RAN node includes an average QoE measurement for one or more QoE metrics.

[0014] In a third aspect, this specification describes a second radio access network (RAN) node (e.g., a target RAN node) of a mobile communication system, the second network node comprising: components (e.g., radio input) for receiving a conditional handover (CHO) request from a first RAN node to configure resources for a user equipment (UE) served by the first RAN node for the CHO; components (e.g., a processor) for generating a CHO request acknowledgment in response to the CHO request, wherein the CHO request acknowledgment includes a conditional handover configuration including information related to the QoE experienced by one or more UEs served by the second RAN node; and components (e.g., radio output) for providing the generated CHO request acknowledgment to the first RAN node.

[0015] Information related to the QoE experienced at one or more UEs served by the second RAN node includes QoE measurements for one or more QoE metrics.

[0016] Information related to the QoE experienced at one or more UEs served by the second RAN node includes an average QoE measurement for one or more QoE metrics.

[0017] The second RAN node may also include a component (e.g., a radio input) for receiving QoE measurement reports from each of one or more UEs served by the second RAN node.

[0018] In a fourth aspect, this specification describes a User Equipment Access Layer (UE-AS) of a mobile communication system, the UE-AS comprising: components (e.g., radio input) for receiving a reconfiguration message (e.g., an RRC reconfiguration message) from a first RAN node (e.g., a source RAN node) serving the UE, the reconfiguration message including a Conditional Handover (CHO) configuration, the CHO configuration including one or more Quality of Experience (QoE) enforcement conditions for one or more target cells associated with one or more target RAN nodes; components (e.g., a processor) for determining whether the QoE enforcement conditions for one or more target cells are satisfied; and components (e.g., instructions transmitted by radio output) for initiating a handover to the target cell if at least the QoE enforcement conditions are satisfied by the target cell.

[0019] The CHO configuration may also include one or more radio execution conditions for one or more target cells associated with one or more target RAN nodes. The UE-AS may also include: components (e.g., a processor) for determining whether the radio conditions for one or more target cells in the target cells satisfy the radio execution conditions; and components (e.g., instructions transmitted by radio output) for initiating a handover to the target cell if both the radio execution conditions and the QoE execution conditions are satisfied by the target cell.

[0020] The UE-AS may also include components (e.g., a processor) for determining QoE conditions for one or more target cells.

[0021] The QoE execution conditions for one or more target cells in the target cells may include at least a QoE threshold associated with one or more QoE metrics.

[0022] The UE-AS may also include components (e.g., a processor) for comparing the QoE execution conditions for one or more target cells with the perceived QoE stored at the UE-AS for one or more QoE metrics.

[0023] If the perceived QoE for QoE measurement is higher than the QoE threshold, the UE can initiate a handover to the target cell.

[0024] The QoE execution conditions for one or more target cells may include at least the QoE metric visible to the RAN.

[0025] The perceived QoE for a QoE metric can be the average perceived QoE measurement over multiple QoE measurements.

[0026] QoE measurements can be performed by the UE application layer (UE APP layer) and are also stored at the UE-AS.

[0027] QoE execution conditions can be based on QoE measurements performed at a UE served by one or more target cells associated with one or more target RAN nodes.

[0028] In a fifth aspect, this specification describes a user equipment (UE) of a mobile communication system, the UE comprising: components (e.g., a radio input) for receiving a reconfiguration message (e.g., an RRC reconfiguration message) from a first RAN node (source RAN node) serving the UE, the RRC reconfiguration message including a conditional handover (CHO) configuration, the CHO configuration including one or more quality of experience (QoE) execution conditions for one or more target cells associated with one or more target RAN nodes; components (e.g., a processor) for determining, at the UE's access stratum (UE-AS), whether the QoE conditions for one or more target cells among the target cells satisfy the QoE execution conditions; and components (e.g., a command transmitted by a radio output) for initiating a handover to a target cell if at least the QoE execution conditions are satisfied by the target cell.

[0029] CHO configuration may include one or more radio execution conditions for one or more target cells associated with one or more target RAN nodes. The UE may also include: components (e.g., a processor) for determining whether the radio conditions for one or more target cells in the target cells satisfy the radio execution conditions; and components (e.g., the instruction) for initiating a handover to the target cell if both the radio execution conditions and the QoE execution conditions are satisfied by the target cell.

[0030] The UE may also include components for determining QoE conditions for one or more target cells at the UE-AS.

[0031] In some example implementations, the QoE conditions for one or more target cells are stored at the UE-AS.

[0032] In some example implementations, the QoE conditions for one or more target cells include RAN-visible QoE measurements.

[0033] The perceived QoE for a QoE metric can be the average perceived QoE measurement over multiple QoE measurements.

[0034] QoE execution conditions can be based on QoE measurements performed at the following UEs: the UE is served by one or more target cells operating under one or more target RAN nodes.

[0035] In a sixth aspect, this specification describes a User Equipment Access Layer (UE-AS) of a mobile communication system, the UE-AS comprising: components (e.g., radio input) for receiving a reconfiguration message (e.g., an RRC reconfiguration message) from a first radio access network (RAN) node (source RAN node) serving the UE, the reconfiguration message including a Conditional Handover (CHO) configuration, the CHO configuration including one or more Quality of Experience (QoE) enforcement conditions for one or more target cells associated with one or more target network nodes; components (e.g., AT command) for sending a request to the UE's application layer (UE APP) to verify whether the QoE enforcement conditions for one or more target cells are satisfied; components (e.g., AT response) for receiving a response from the UE APP layer indicating whether the QoE conditions for one or more target cells are satisfied; and components (e.g., instructions transmitted by radio output) for initiating a handover to a target cell if at least the QoE enforcement conditions are satisfied by the target cell.

[0036] The CHO configuration includes one or more radio execution conditions for one or more target cells associated with one or more target RAN nodes. The UE-AS may also include: components (e.g., a processor) for determining whether the radio conditions for one or more target cells satisfy the radio execution conditions; and components (e.g., the instruction sent by the radio output) for initiating a handover to the target cell if both the radio execution conditions and the QoE execution conditions are satisfied by the target cell. The UE-AS may also include components (e.g., a processor or input) for determining the radio conditions for one or more target cells.

[0037] Requests to the UE APP layer to verify whether the QoE execution conditions are met may include AT commands.

[0038] The UE-AS may also include components (e.g., radio output) for providing radio measurements to the first RAN node.

[0039] In some example implementations, QoE execution conditions are based on QoE measurements performed at a UE served by one or more target cells associated with one or more target RAN nodes.

[0040] In some example implementations, the QoE execution conditions for one or more target cells in the target cells include at least a QoE threshold associated with one or more QoE metrics.

[0041] In a seventh aspect, this specification describes a user equipment (UE) comprising: components (e.g., a radio input) for receiving a reconfiguration message (e.g., an RRC reconfiguration message) from a first radio access network (RAN) node serving the UE, the reconfiguration message including a conditional handover (CHO) configuration, the CHO configuration including one or more quality of experience (QoE) execution conditions for one or more target cells associated with one or more target network nodes; components (e.g., an AT command) for obtaining an indication from the UE's application layer (UE APP) of whether the QoE execution conditions for one or more target cells are satisfied; and components (e.g., an instruction transmitted by a radio output) for initiating a handover to a target cell if at least one of the target cells' QoE execution conditions are satisfied.

[0042] The CHO configuration includes one or more radio execution conditions for one or more target cells associated with one or more target RAN nodes. The UE may also include: components (e.g., a processor or input) for determining whether the radio conditions for one or more target cells satisfy the radio execution conditions; and components (e.g., the instruction sent by the radio output) for initiating a handover to the target cell if both the radio execution conditions and the QoE execution conditions are satisfied by the target cell. The UE may also include components for determining the radio conditions for one or more target cells.

[0043] In some example implementations, the radio conditions for the corresponding target cell are determined by the UE-AS layer.

[0044] QoE execution conditions can be based on QoE measurements performed at a UE operating in one or more target cells associated with one or more target RAN nodes.

[0045] QoE execution conditions can be based on QoE measurements performed at a UE served by one or more target cells associated with one or more target RAN nodes.

[0046] The QoE execution conditions for one or more target cells in the target cells may include at least a QoE threshold associated with one or more QoE metrics.

[0047] The UE may also include: components (e.g., a processor) for generating QoE measurement reports; and components (e.g., an output) for providing QoE measurement reports to a first RAN node.

[0048] The UE may also include components (e.g., radio output) for providing radio measurements to the first RAN node.

[0049] In an eighth aspect, this specification describes a method comprising: at a user equipment (UE), receiving a reconfiguration message (e.g., an RRC reconfiguration message) from a first radio access network (RAN) node (e.g., a source RAN node) serving the UE, the reconfiguration message including a conditional handover (CHO) configuration, the CHO configuration including one or more Quality of Experience (QoE) enforcement conditions for one or more target cells associated with one or more target network nodes; and determining, at least in part, whether to trigger a handover from a cell served by the first RAN node to one of the one or more target cells based on whether the QoE enforcement conditions in the CHO configuration for the respective target cell are met. Whether the QoE enforcement conditions for the respective target cell are met can be determined based on QoE measurements obtained by the UE's application layer (UE APP layer).

[0050] The method may also include generating a QoE measurement report. The generated QoE measurement report can be provided to the first RAN node.

[0051] The QoE execution conditions defined in the CHO configuration can be based on QoE measurements generated by other UEs operating with one or more target cells.

[0052] The CHO configuration includes one or more radio execution conditions for one or more target cells associated with one or more target RAN nodes. The method may further include determining whether a handover from a cell associated with a first RAN node to one of the one or more target cells is triggered based on whether the radio execution conditions included in the CHO configuration are met by the corresponding target cell.

[0053] In a ninth aspect, this specification describes a method comprising: sending a Conditional Handover (CHO) request from a first RAN node to one or more target RAN nodes to configure resources for a User Equipment (UE) served by the first RAN node for CHO purposes; receiving a CHO request acknowledgment from one or more target RAN nodes in response to the CHO request, wherein each CHO request acknowledgment includes a CHO configuration, the CHO configuration including information related to QoE experienced by one or more UEs served by a corresponding target network node; determining CHO conditions for one or more target cells associated with one or more target RAN nodes; and providing a reconfiguration message (e.g., an RRC reconfiguration message) to the UE, wherein the reconfiguration message includes a Conditional Handover CHO configuration, the CHO configuration including one or more QoE enforcement conditions for one or more target cells associated with one or more target RAN nodes. The CHO configuration includes one or more radio enforcement conditions for one or more target cells associated with one or more target RAN nodes.

[0054] The first RAN node can send a QoE measurement configuration request to the UE, where the QoE measurement configuration request is an RRC reconfiguration request. The first RAN node can respond to the QoE measurement configuration request by receiving a QoE measurement report from the UE.

[0055] The first RAN node can receive radio measurements from the UE and can make CHO configuration decisions based at least in part on the received radio messages.

[0056] In some example embodiments, information related to the QoE experienced at one or more UEs served by a corresponding target RAN node may include QoE measurements for one or more QoE metrics.

[0057] In some example embodiments, information related to the QoE experienced at one or more UEs served by the respective target RAN node may include an average QoE measurement against one or more QoE metrics.

[0058] In a tenth aspect, this specification describes a method comprising: (at a second RAN node of a mobile communication system, such as a target RAN node) receiving a Conditional Handover (CHO) request from a first RAN node to configure resources for a User Equipment (UE) served by the first RAN node for the CHO; generating a CHO request acknowledgment in response to the CHO request, wherein the CHO request acknowledgment includes a Conditional Handover configuration, the Conditional Handover configuration including information related to the QoE experienced by one or more UEs served by the second RAN node; and providing the generated CHO request acknowledgment to the first RAN node.

[0059] Information related to the QoE experienced at one or more UEs served by the second RAN node may include QoE measurements for one or more QoE metrics.

[0060] Information related to the QoE experienced at one or more UEs served by the second RAN node may include an average QoE measurement against one or more QoE metrics.

[0061] The method may include receiving a QoE measurement report from each of one or more UEs served by the second RAN node (at the second RAN node).

[0062] In an eleventh aspect, this specification describes a method comprising: receiving, at a UE of a mobile communication system, a reconfiguration message (e.g., an RRC reconfiguration message) from a first RAN node (source RAN node) serving the UE, the reconfiguration message including a conditional handover CHO configuration, the CHO configuration including one or more Quality of Experience (QoE) enforcement conditions for one or more target cells associated with one or more target RAN nodes; at the UE's access stratum UE-AS, determining whether the QoE conditions for one or more target cells are satisfied; and, if at least the QoE enforcement conditions are satisfied by the target cells, initiating a handover to the target cells.

[0063] CHO configuration includes one or more radio execution conditions for one or more target cells associated with one or more target RAN nodes. The method may further include: determining whether the radio conditions for one or more target cells satisfy the radio execution conditions; and, if both the radio execution conditions and the QoE execution conditions are satisfied by the target cells, initiating a handover to the target cells.

[0064] This method may include determining QoE conditions for one or more target cells at the UE-AS.

[0065] The QoE conditions for one or more target cells can be stored at the UE-AS.

[0066] In some example implementations, the QoE conditions for one or more target cells include RAN-visible QoE measurements.

[0067] The method may include generating a sensed QoE for a QoE metric by averaging sensed QoE measurements over multiple QoE measurements.

[0068] QoE execution conditions can be based on QoE measurements performed at the following UEs: the UE is served by one or more target cells operating under one or more target RAN nodes.

[0069] In a twelfth aspect, this specification describes a method comprising: receiving, at the User Equipment Access Layer (UE-AS) of a mobile communication system, a reconfiguration message (e.g., an RRC reconfiguration message) from a first Radio Access Network (RAN) node serving the UE, the reconfiguration message including a Conditional Handover (CHO) configuration, the CHO configuration including one or more Quality of Experience (QoE) enforcement conditions for one or more target cells associated with one or more target network nodes; sending (e.g., to the UE's Application Layer) a request to verify whether the QoE enforcement conditions for one or more target cells are satisfied; receiving (e.g., from the UE APP) a response indicating whether the QoE conditions for one or more target cells are satisfied; and initiating a handover to a target cell if at least the QoE enforcement conditions are satisfied by the target cell.

[0070] CHO configuration includes one or more radio execution conditions for one or more target cells associated with one or more target RAN nodes. The method may further include: determining whether the radio conditions for one or more target cells satisfy the radio execution conditions; and, if both the radio execution conditions and the QoE execution conditions are satisfied by the target cells, initiating a handover to the target cells. The UE may also include components for determining the radio conditions for one or more target cells.

[0071] In some example implementations, the radio conditions for the corresponding target cell are determined by the UE-AS layer.

[0072] QoE execution conditions may be based on QoE measurements performed at a UE operating in one or more target cells associated with the one or more target RAN nodes.

[0073] QoE execution conditions can be based on QoE measurements performed at a UE served by one or more target cells associated with one or more target RAN nodes.

[0074] The QoE execution conditions for one or more target cells in the target cells may include at least a QoE threshold associated with one or more QoE metrics.

[0075] The method may also include generating a QoE measurement report and providing the QoE measurement report to the first RAN node.

[0076] The method may also include providing radio measurements to the first RAN node.

[0077] In a thirteenth aspect, this specification describes computer-readable instructions that, when executed by a computing device, cause the computing device to perform (at least) any of the methods described herein (including the methods described in aspects eight through twelfth above).

[0078] In its fourteenth aspect, this specification describes a computer-readable medium (such as a non-transitory computer-readable medium) including program instructions stored thereon for performing (at least) any of the methods described herein (including the methods described in aspects eight through twelfth above).

[0079] In the fifteenth aspect, this specification describes a computer program product comprising program instructions that, when executed by a device, cause the device to perform (at least) any of the methods described herein (including the methods described in aspects eight through twelfth above).

[0080] In a sixteenth aspect, this specification describes an apparatus comprising: at least one processor; and at least one memory storing instructions that, when executed by the at least one processor, cause the apparatus to perform (at least) any of the methods described herein (including the methods described in aspects eight through twelfth above). Attached Figure Description

[0081] Exemplary embodiments will now be described by way of non-limiting example with reference to the accompanying drawings, in which: Figure 1 This is a block diagram of the example system; Figure 2 It shows that it can be used Figure 1 The flowchart of the system's conditional switching arrangement; Figure 3 An example message stream sequence is shown; Figure 4 It is a message stream sequence according to the example embodiment; Figure 5 It is a message stream sequence according to the example embodiment; Figure 6 A flowchart according to an example embodiment is shown; Figure 7 It is a message stream sequence according to the example embodiment; Figure 8 It is a message stream sequence according to the example embodiment; Figure 9 These are schematic diagrams of systems that can be used to implement one or more example embodiments in the example embodiments; and Figure 10A tangible medium for storing computer-readable code is shown, which, when run by a computer, can perform methods according to the example embodiments described herein. Detailed Implementation

[0082] Figure 1 This is a block diagram of an example system generally indicated by reference numeral 10. System 10 includes a user equipment (UE) 12 of a mobile communication system, a source radio access network (RAN) node 14, a first target RAN node 16, a second target RAN node 17, and a third target RAN node 18. Source RAN node 14 and target RAN nodes 16 through 18 can all be next-generation node B (gNB). It should be noted that the terms source RAN, source node, and source network node are used interchangeably herein. Similarly, the terms target RAN, target node, and target network node are used interchangeably herein. Furthermore, the source RAN and target RAN constitute part of a mobile communication system, which includes multiple RANs, multiple UEs, and a core network.

[0083] Initially, UE 12 is served by the cell associated with the source RAN node 14. If a target cell associated with one of the target RAN nodes in the target RAN nodes offers better options for communication (based on some metric, such as radio signal strength), a handover procedure can be initiated to make that target RAN node the source RAN node for the UE.

[0084] Figure 2 The flowchart, generally indicated by reference numeral 20, illustrates a conditional switching (CHO) arrangement that can be implemented using system 10.

[0085] The flowchart begins with operation 22, where CHO conditions are provided to UE 12. This step can be used to configure the UE with a CHO command containing the target cell configuration, as well as conditions for performing a handover for one or more target cells. These conditions are typically based on radio measurements from neighboring cells.

[0086] In operation 24, CHO conditions are evaluated at UE 12. For example, the radio conditions of neighboring (target) cells can be evaluated.

[0087] If the CHO condition triggers a handover, then a handover occurs in operation 26. It should be noted that the handover occurs under the control of the UE and the relevant target RAN node, without requiring the source RAN node 14 to trigger the handover execution.

[0088] Figure 3 An example message flow sequence, generally indicated by reference numeral 30, is shown. Sequence 30 can be used in the example implementation of flowchart 20 in the case of conditional switching within a new radio (NR).

[0089] Sequence 30 illustrates the messages transmitted between UE 12, source RAN node 14, first target RAN node 16 and other potential / candidate target RAN nodes 17 and target RAN node 18 in system 10, and also illustrates the user plane function UPF 31 and access and mobility management function AMF 32 of the relevant core network of the communication system.

[0090] In step 1, UE 12 sends a measurement report to source RAN node 14 (e.g., serving gNB), which contains measurement results for neighboring cells.

[0091] In step 2, source RAN node 14 identifies the need to trigger a CHO (i.e., to make a CHO decision).

[0092] In steps 3 and 4, source RAN node 14 sends a request to the corresponding target node, requesting CHO configuration for the target cell used for the UE's CHO. Specifically, as shown in the figure, in step 3, the CHO request is sent to the first target RAN node 16, and in step 4, the CHO request is sent to other potential / candidate target RAN nodes 17 and target RAN node 18. The CHO configuration includes the radio protocol configuration applied by the UE when handing over to the target cell associated with the target node.

[0093] In steps 5 and 6, the corresponding target node performs admission control and generates the requested CHO configuration.

[0094] In step 7, the first target RAN node 16 sends a CHO request confirmation message to the source RAN node 14, which includes the requested CHO configuration for the first target RAN node 16. Similarly, in step 8, other target nodes send CHO request confirmation messages to the source RAN node, which include the CHO configuration for the respective target node.

[0095] Source RAN node 14 associates each CHO configuration with a CHO execution condition, which refers to the measurement ID in the source cell measurement configuration. The measurement ID links the measurement object to a reporting configuration that defines the frequency and metric of the measurement (e.g., radio conditions such as RSRP, RSRQ, etc.), and the reporting configuration defines parameters of the event that triggers the CHO execution (e.g., offset, trigger time to trigger (TTT), or other thresholds). For intra-frequency handovers, measurement event A3 can be used (e.g., Mn>Ms + Off, where Mn is the measurement of the neighboring cell, Ms is the measurement of the target cell, and Off is the offset). Furthermore, the UE can execute a CHO if the above conditions are met for a specific trigger time (TTT). For inter-frequency handovers, measurement event A5 can be used, where the UE checks whether, for a specific TTT, the serving cell's measurement is below threshold 1 and the target cell's measurement is above threshold 2. Details of example measurement configurations and events can be found in 3GPP TS 38.331.

[0096] In step 9, the source RAN node 14 sends an RRC reconfiguration message to the UE 12. This RRC reconfiguration message includes the prepared CHO configuration for the target cell and its corresponding CHO execution conditions. It should be noted that the terms "CHO ​​execution conditions" and "CHO ​​conditions" are generally used interchangeably in this document.

[0097] In step 10, UE 12 evaluates the CHO execution conditions (as provided in step 9). If the conditions for the prepared target cell are met (as shown in step 11), UE 12 applies the corresponding CHO configuration and performs a handover, as shown in steps 12 to 19.

[0098] In step 19, source RAN node 14 cancels CHO preparation, which has not yet been selected by the UE for handover execution.

[0099] In step 20, a path switch is performed from the source node to the target node (in this example, the first target RAN node 16).

[0100] When deciding whether to switch from a cell associated with a source node to a target cell associated with a target node, the aforementioned CHO procedure in reference message sequence 30 does not consider the UE's Quality of Experience (QoE). Therefore, in some cases, when a UE moves from a cell associated with a source node to a target cell associated with a target node, it may experience a worse QoE, potentially leading to user dissatisfaction.

[0101] In some existing algorithms, to support UEQoE reporting continuity when the UE is configured by the source RAN node to perform QoE measurements, the QoE measurement configuration is transmitted from the source node to the target node during UE handover. However, information about QoE measurements is typically not shared between the source and target RAN nodes.

[0102] 3GPP has worked on a Quality of Experience (QoE) Measurement Acquisition (QMC) framework for obtaining QoE measurements from the UE to consumers of such measurements (e.g., the Orchestration and Management (OAM) entity of the communications system).

[0103] For DASH, VR, and MTSI services, QoE metrics are specified. Each service is associated with a corresponding QoE metric to be measured by the UE. Some of these QoE metrics include: average throughput, initial playback latency, buffer level, comparable quality viewport switching latency, frame rate, jitter duration, etc.

[0104] The new radio NR QoE has two types of measurement activation methods: signaling-based QoE measurement and management-based QoE measurement. Since 3GPP Release 17, NR QoE also supports RAN-visible QoE (RVQoE) measurement collection. RAN-visible QoE measurements are configured at the UE by the appropriate RAN node, where a subset of the configured QoE metrics is reported from the UE to the RAN node in the form of an explicit information element (IE) readable by the RAN node. RAN-visible QoE measurements can be used by the RAN node for RAN-specific optimizations (e.g., scheduling decisions). The RAN node configures some or all of the available RAN-visible QoE (RVQoE) metrics, where an indication of the availability of RAN-visible QoE metrics is received by the RAN node as part of a management-based or signaling-based QoE configuration. Available RVQoE metrics may include, for example, application layer buffer levels and playback delays for media initiation. As specified in 3GPP TS 38.331, the UE can report RVQoE measurements together with container-based QoE measurements in the MeasurementReportAppLayer message.

[0105] Figure 4 This is a message flow sequence generally indicated by reference numeral 40 according to an exemplary embodiment. Sequence 40 illustrates the messages transmitted and actions taken between UE 41 (similar to UE 12 described above), source RAN node 42 (similar to source RAN node 14), and target RAN node 43 (similar to target RAN node 16). As mentioned above, target RAN node 43 can be one of a plurality of potential / candidate target nodes (for clarity, ...). Figure 4Other target nodes are omitted.

[0106] UE 41 is configured to generate a report to be sent to source RAN node 42 (similar to the measurement report sent in step 1 of message sequence 30 above). The UE is configured to perform QoE measurements and generate a QoE measurement report, which is provided to source RAN node 42 in message 44a. The QoE measurement report may include container-based QoE measurements and RVQoE measurements. As discussed further below, message 44a may be sent in response to a QoE measurement configuration request sent from source RAN node 42 to UE 41. UE 41 also generates and sends a radio report containing measurement results for neighboring cells, in message 44b.

[0107] The order in which reports 44a and 44b are sent does not need to be as shown in sequence 40. In fact, in some example embodiments, the reports may be combined into a single report.

[0108] In step 45 of sequence 40, a CHO decision is made at the source RAN node. In example message sequence 40, the CHO decision is used to trigger a CHO. The decision can be made based on the content of the radio report received in message 44b. Therefore, step 45 is similar to step 2 of message sequence 30 (where the CHO decision is made based on the content of the measurement report received in step 1 of sequence 30).

[0109] Upon CHO triggering, a CHO request 46a is sent from source RAN node 42 to one or more target RAN nodes (including target RAN node 43) to configure resources for CHO for the user equipment in the target RAN nodes. Such resources include radio protocol configurations that the UE needs to apply when handing over to the appropriate target cell associated with the target RAN node.

[0110] In response to CHO request 46a, a CHO request acknowledgment 46b is generated at target RAN node 43 (and optionally other target RAN nodes) and provided to source RAN node 42. Each CHO request acknowledgment includes a CHO configuration that includes information related to the QoE experienced / perceived by one or more UEs served by the corresponding target RAN node. The information related to the QoE experienced at one or more UEs served by the corresponding target RAN node may include QoE measurements for one or more QoE metrics and / or RVQoE metrics, or an average of multiple QoE measurements for one or more QoE metrics and / or RVQoE metrics.

[0111] CHO request 46a is similar to steps 3 and 4 of message sequence 30, but CHO request acknowledgment 46b is different from the acknowledgments sent in steps 7 and 8 of message sequence 30, the difference being that it includes QoE measurement.

[0112] The source RAN node 42 sends a CHO configuration 47 to the UE 41 (e.g., using an RRC reconfiguration message). The CHO configuration includes at least one or more QoE enforcement conditions for one or more target cells associated with the target RAN node 43, and may include both radio enforcement conditions and QoE enforcement conditions.

[0113] Therefore, when a source RAN node (such as source RAN node 42) requests a target RAN node (such as target RAN node 43) to prepare a cell for conditional handover for a UE (e.g., UE 41), the target RAN node may provide CHO radio conditions and QoE information in its response to the source RAN node. For example, the QoE information may include the average of QoE measurements experienced by the UE within the cell associated with the target RAN node for one or more QoE metrics and / or RVQoE metrics, or actual QoE measurements from the UE within the cell associated with the target RAN node, for a specific application, for one or more QoE metrics and / or RVQoE metrics. Based on the QoE information received by the target RAN node, the source RAN node may derive the QoE execution conditions and send the derived QoE execution conditions, along with the CHO radio conditions for one or more target cells, to the UE.

[0114] In step 48, UE 41 determines whether to trigger a handover from the cell associated with source RAN node 41 to one of one or more target cells associated with one or more target RAN nodes (e.g., target RAN node 43) based on a comparison of at least the QoE conditions for the corresponding potential target cell with the QoE execution conditions included in the CHO configuration. (The handover can also be triggered based on a comparison of the radio execution and QoE conditions for the corresponding potential / candidate target cell with the radio execution conditions and QoE execution conditions included in the CHO configuration.)

[0115] The UE determines whether the QoE execution conditions defined in the CHO configuration are met by one or more target cells. As discussed in detail below, whether the defined QoE execution conditions are met can be determined (at least in part) by the UE's application layer, the UE APP layer.

[0116] Figure 5 It is a message flow sequence generally indicated by reference numeral 50 according to the example embodiment. Sequence 50 can be used in the example implementation of sequence 40 described above.

[0117] Sequence 50 illustrates the messages transmitted between a first gNB (gNB1) 51 (similar to first target RAN node 16 and target RAN node 43), a second gNB (gNB2) 52 (similar to source RAN node 14 and source RAN node 42), a first UE (UE1) 53, and a second UE (UE2) (similar to UE12 and UE41). UE2 has a UE access layer UE2-AS 54 and a UE application layer UE2-APP 55.

[0118] In step 1, the target RAN node gNB1 51 provides QoE measurement configuration to UE1 53 operating in the cell associated with gNB1. Specifically, gNB1 uses the RRCReconfiguration message to provide QoE measurement configuration for a specific application (application 1 in this example).

[0119] UE1 53 performs a QoE measurement for Application 1 and provides the QoE measurement to gNB1 in the AppLayer Measurement report via Signal Radio Bearer 4 (SRB4). In step 3, UE1 additionally provides gNB1 with a RAN-visible QoE (RVQoE) measurement for further processing. In this way, the target RAN node gNB1 51 can obtain QoE information from UE1. It should be understood that gNB1 can receive QoE measurements from other UEs in the cell associated with gNB1 in a similar manner.

[0120] In step 4, the source RAN node gNB2 provides QoE measurement configuration to UE2 operating in the cell associated with gNB2. Specifically, gNB2 uses the RRCReconfiguration message to send the QoE measurement configuration for application 1 to the UE2 access layer UE2-AS. In step 5, UE2-AS sends the QoE measurement configuration to the UE2 APP layer via AT commands.

[0121] In step 6, the UE2 APP layer performs QoE measurements for application 1 and sends the measurements to gNB2. Specifically, the UE2 APP layer 56 provides the measurements to the UE2-AS via AT commands (step 7). The UE2-AS 54 provides the QoE measurements to gNB2 via SRB4 in an AppLayer Measurement report, which includes RVQoE measurements for further processing (step 8). (It should be understood that, although...) Figure 5 (It is not explicitly stated that UE1 may have a similar UE-AS and UE APP structure and functions) In step 9, UE2 provides radio measurements to the target RAN node gNB2 for handover decision-making (similar to message 44b in message sequence 40). In step 10, gNB2 decides to configure a CHO for UE2 (similar to step 45 in message sequence 40). In step 11, the source RAN node gNB2 sends a CHO request to the target RAN node gNB1 (similar to message 46a in message sequence 40).

[0122] In step 12, gNB1 51 performs admission control. Then, in step 13, gNB1 sends a CHO request confirmation to gNB2 (similar to message 46b in message sequence 40). The target RAN node gNB1 provides gNB2 with a CHO configuration for the UE, which includes QoE measurements of one or more QoE metrics / RVQoE metrics for other UEs in the cell associated with gNB1, or an average of one or more QoE metrics and / or RVQoE metrics experienced by the UE for one or more application and service types, operating in the cell associated with gNB1. Therefore, the source RAN node gNB2 52 is provided with the QoE information of the UE in the cell associated with the target RAN node gNB1 51.

[0123] In this variant, the average QoE at the target cell is categorized based on the device capabilities associated with the device experiencing a given QoE. For example, if we assume the set of device capabilities comprises three levels (i.e., low, medium, and high capabilities), the average QoE can be applied to a given capability level. In this variant, gNB1 51 can provide gNB2 52 with a list (table) that includes the average QoE for each capability level perceived by the UE in the cell associated with gNB1.

[0124] In step 14, gNB2 provides the CHO configuration to the UE, which includes CHO radio execution conditions and QoE execution conditions for one or more target cells (similar to message 47 in sequence 40). UE2 is then able to make a CHO decision (thus implementing step 48 of sequence 40).

[0125] Figure 6 A flowchart, generally indicated by reference numeral 60, is shown according to an example embodiment.

[0126] Flowchart 60 begins with the UE (e.g., the access layer of UE 61) receiving a CHO configuration from a source RAN node (such as source RAN node 62). The CHO configuration may include at least one or more QoE execution conditions (which may include radio execution conditions and QoE execution conditions) for one or more target cells associated with one or more target RAN nodes.

[0127] In step 63, it is determined whether the radio conditions defined in the CHO configuration are satisfied by one or more target cells in the target cells. If yes, the flowchart proceeds to step 64; otherwise, the flowchart terminates in step 66 (where no handover is performed).

[0128] In step 64, it is determined whether the QoE execution conditions defined in the CHO configuration are met by one or more target cells. If so, the flowchart moves to step 65 (where a handover is performed); otherwise, the flowchart terminates in step 66 (where no handover is performed). QoE execution conditions can be set for one or more QoE metrics for one or more potential / candidate target cells. Examples of QoE execution conditions include specifying that if the playback delay for media initiation in the source cell is greater than 3 milliseconds, the UE should handover to the target cell (so that the target cell can provide better performance for that QoE / RVQoE metric). In a variant, QoE execution conditions for one or more QoE metrics are provided separately for each UE (device) capability type. In this way, the UE can associate itself with the appropriate capability type and evaluate which conditions are considered for the CHO.

[0129] Of course, flowchart 60 is highly illustrative. Steps 63 and 64 may be performed, for example, in a different order or in parallel. Furthermore, in some example embodiments, step 64 may be performed without evaluating whether the radio conditions are met (i.e., step 63 may be omitted or implemented in some other way).

[0130] Figure 7 This is a sequence of message flows generally indicated by reference numeral 70 according to an exemplary embodiment. Sequence 70 illustrates the messages transmitted between the UE access layer UE-AS 71, the source RAN node 72, and the target RAN node 73, and the actions taken therein. The UE-AS constitutes part of the UE. The target RAN node 73 may be one of a plurality of potential / candidate target RAN nodes.

[0131] Message sequence 70 begins with a CHO configuration provided to UE-AS 71 by source RAN node 72. As described above, the CHO configuration can be provided using an RRC reconfiguration message and can include radio execution conditions and Quality of Experience (QoE) execution conditions for one or more target cells (such as the cell associated with target RAN node 73). Therefore, UE-AS 71 receives the CHO configuration, which includes CHO radio conditions for a set of candidate target cells and a set of QoE conditions for the set of target cells. The QoE condition set may be, for example, that the UE does not perform a handover if the QoE of a particular QoE metric experienced / perceived by the UE in the current cell is better than the QoE metric perceived in the target cell. (Note that, as described above, in some example embodiments, the radio execution conditions may be omitted from the CHO configuration.) Therefore, message 74 of message sequence 70 is an example implementation of step 62 of the above flowchart 60.

[0132] In steps 76 and 77, UE-AS 71 evaluates CHO conditions (particularly radio conditions and QoE conditions).

[0133] Specifically, in step 76, UE-AS 71 determines whether the radio conditions for one or more target cells in the target cells meet the radio execution conditions (thus implementing step 63 of flowchart 60), and in step 77, UE-AS determines whether the QoE conditions for one or more target cells in the target cells meet the QoE execution conditions (thus implementing step 64 of flowchart 60). As mentioned above, these steps can be implemented simultaneously or in reverse order, and in some example embodiments, step 76 may be omitted or implemented elsewhere.

[0134] Step 77 may include determining the QoE conditions for one or more target cells at UE-AS 71. For example, QoE / RVQoE measurements used to determine whether the QoE conditions for one or more target cells are met may be stored at UE-AS.

[0135] The QoE conditions determined as part of step 77 can be based on RAN-visible QoE measurements or other QoE measurements received by the UE APP layer for a specific application or application type. The UE-AS may store only the most recent measurements received by the UE APP layer, or the average of the last x QoE / RVQoE measurements. For example, QoE measurements may be performed at the UE APP layer and sent to the RAN, where the UE-AS stores some of the measurements and uses them for the QoE condition evaluation in step 77. Such QoE measurements may be outdated, but have the advantage of being readily available and timely to the UE-AS.

[0136] If the execution conditions (e.g., both radio execution conditions and QoE execution conditions) are met in a specific target cell, the UE initiates a handover to that target cell (message 78), thereby implementing step 65 of flowchart 60.

[0137] In step 77, UE-AS 71 can compare the QoE perceived in the current cell for one or more QoE metrics / RVQoE metrics with the relevant CHO QoE threshold set in the QoE conditions for one or more QoE metrics.

[0138] The QoE CHO condition can also include the actual / average QoE value of the metric perceived by the target cell. In this case, the UE-AS can find one or more target cells that meet the radio conditions and then sort these cells according to the QoE perceived at the target cell for one or more QoE / RVQoE metrics. The UE can then (in step 78) switch to the target cell that provides the best QoE experience / perception for the specific QoE / RVQoE metric. For example, if it is possible to switch to both target cell 1 and target cell 2 from the perspective of radio conditions, and the QoE for media start playback delay perceived at target cell 1 is 5 milliseconds, while the QoE for media start playback delay perceived at target cell 2 is 2 milliseconds, then the UE-AS can choose to switch to target cell 2.

[0139] Figure 8 It is the message flow sequence generally indicated by reference numeral 80 according to the example embodiment.

[0140] Sequence 80 illustrates the messages transmitted between the source RAN node 72 and the destination RAN node 73 of message sequence 70 and UE-AS 81 and UE application layer UE APP layer 82, and the actions taken therein. UE-AS and UE APP constitute part of the UE.

[0141] Message sequence 80 begins with a CHO configuration provided to UE-AS 81 by source RAN node 72. As described above, the CHO configuration can be provided using an RRC reconfiguration message and may include radio enforcement conditions and Quality of Experience (QoE) enforcement conditions for one or more target cells (such as the cell associated with target RAN node 73). Therefore, UE-AS 81 receives the CHO configuration, which includes CHO radio conditions for a set of potential / candidate target cells and a set of QoE conditions for the set of candidate / potential target cells. As described above, in some example embodiments, the radio enforcement conditions may be omitted from the CHO configuration.

[0142] In step 84, the UE-AS determines whether the radio conditions for one or more target cells in the target cells meet the radio execution conditions (as in step 76 of message sequence 70). (As discussed elsewhere, in some example embodiments, step 84 may be omitted or performed elsewhere.) In steps 85 to 87, UE-AS 81 determines whether the QoE conditions for one or more target cells in the target cells meet the QoE execution conditions by: sending a request (e.g., AT command 85) to UE APP 82 to verify whether the QoE execution conditions for one or more target cells in the target cells are met, and receiving a response (e.g., AT response 87) from UE APP indicating whether the QoE conditions for one or more target cells in the target cells meet the QoE execution conditions.

[0143] If the execution conditions (e.g., both radio execution conditions and QoE execution conditions) are met by a specific target cell, UE-AS 81 initiates a handover to the target cell (message 88, which is similar to message 78 above).

[0144] For example, in message sequence 70, UE-AS 81 receives a CHO configuration, which includes CHO radio conditions for the candidate target cell set and a set of QoE execution conditions for the target cell set. The QoE execution conditions set could be, for example, that no handover is performed if the QoE of a specific QoE metric perceived in the current cell is superior to the QoE metric perceived in the target cell. When UE-AS 81 finds one or more target cells that meet the radio conditions, UE-AS can request UE APP layer 82 via AT command to compare the QoE perceived in the current cell with the CHO QoE threshold set in the QoE conditions for the specific QoE metric. The UE APP layer then provides a response to UE-AS via AT command indicating whether the QoE conditions are met. UE-AS then decides whether to handover to the target cell.

[0145] It should be noted that one advantage of message sequence 80 over message sequence 70 is that the verification of whether one or more QoE execution conditions are met may be more accurate and / or based on more complete and / or up-to-date measurements. However, message sequence 70 may be faster because it can be performed directly as UE-AS (without involving the UE APP); this may be preferred in some cases.

[0146] This disclosure provides the following examples.

[0147] Example 1. A User Equipment Access Layer (UE-AS) of a mobile communication system, the UE-AS comprising: at least one processor; and at least one memory, the at least one memory storing instructions, the instructions being executed by the at least one processor: The system receives a reconfiguration message from the first radio access network (RAN) node serving the UE. The reconfiguration message includes a conditional handover (CHO) configuration, which includes one or more Quality of Experience (QoE) enforcement conditions for one or more target cells associated with one or more target network nodes. The system then sends a request to the UE's application layer (UE APP) to verify whether the QoE enforcement conditions for one or more target cells are met. The system receives a response from the UE APP indicating whether the QoE conditions for one or more target cells are met. Finally, if at least the QoE enforcement conditions are met by the target cells, the system initiates a handover to the target cell.

[0148] Example 2. The UE-AS of claim 1, wherein the CHO configuration includes one or more radio execution conditions for one or more target cells associated with one or more target RAN nodes, and wherein the instructions further cause the UE-AS to: determine whether the radio conditions for one or more target cells in the target cells satisfy the radio execution conditions; and, if both the radio execution conditions and the QoE execution conditions are satisfied by the target cells, initiate a handover to the target cells.

[0149] Example 3. The UE-AS of claim 2, wherein the instructions further cause the UE-AS to at least: determine radio conditions for one or more target cells.

[0150] Example 4. UE-AS according to any one of claims 1 to 3, wherein the request to the UE APP layer for verifying whether the QoE execution conditions are met includes an AT command.

[0151] Example 5. The UE-AS according to any one of the preceding claims, wherein the instructions further cause the UE to at least: provide radio measurements to the first RAN node.

[0152] Example 6. A UE-AS according to any of the preceding claims, wherein the QoE execution conditions are based on QoE measurements performed at a UE served by one or more target cells associated with one or more target RAN nodes.

[0153] Example 7. The UE-AS according to any of the preceding claims, wherein the QoE execution conditions for one or more target cells in the target cells include at least a QoE threshold associated with one or more QoE metrics.

[0154] Example 8. A user equipment (UE) includes: at least one processor; and at least one memory, the at least one memory storing instructions that, when executed by the at least one processor: receive a reconfiguration message from a first radio access network (RAN) node serving the UE, the reconfiguration message including a conditional handover (CHO) configuration, the CHO configuration including one or more Quality of Experience (QoE) execution conditions for one or more target cells associated with one or more target network nodes; obtain from the UE's application layer (UE APP) an indication of whether the QoE execution conditions for one or more target cells are satisfied; and, if at least one of the target cells is satisfied, initiate a handover to the target cell.

[0155] Example 9. The UE of claim 8, wherein the CHO configuration includes one or more radio execution conditions for one or more target cells associated with one or more target RAN nodes, and wherein the instructions further cause the UE to: determine whether the radio conditions for one or more target cells in the target cells satisfy the radio execution conditions; and, if both the radio execution conditions and the QoE execution conditions are satisfied by the target cells, initiate a handover to the target cells.

[0156] Example 10. The UE of claim 9, wherein the instructions further cause the UE to at least: determine radio conditions for one or more target cells.

[0157] Example 11. The UE of claim 10, wherein the radio conditions for the corresponding target cell are determined by the UE-AS layer.

[0158] Example 12. A UE according to any one of claims 8 to 11, wherein the QoE execution conditions are based on QoE measurements performed at the UE operating in one or more target cells associated with one or more target RAN nodes.

[0159] Example 13. A UE according to any one of claims 8 to 12, wherein the QoE execution conditions are based on QoE measurements performed at the UE served by one or more target cells associated with one or more target RAN nodes.

[0160] Example 14. The UE according to any one of claims 8 to 13, wherein the QoE execution conditions for one or more target cells in the target cells include at least a QoE threshold associated with one or more QoE metrics.

[0161] Example 15. A UE according to any one of claims 8 to 14, wherein the instructions further cause the UE to at least: generate a QoE measurement report; and provide the QoE measurement report to a first RAN node.

[0162] Example 16. The UE according to any one of claims 8 to 15, wherein the instructions further cause the UE to at least: provide radio measurements to the first RAN node.

[0163] Example 17. A method comprising: receiving, at the User Equipment Access Layer (UE-AS) of a mobile communication system, a reconfiguration message from a first Radio Access Network (RAN) node serving the UE, the reconfiguration message including a Conditional Handover (CHO) configuration, the CHO configuration including one or more Quality of Experience (QoE) enforcement conditions for one or more target cells associated with one or more target network nodes; sending a request to the UE's Application Layer (UE APP) to verify whether the QoE enforcement conditions for one or more target cells are satisfied; receiving a response from the UE APP indicating whether the QoE enforcement conditions for one or more target cells are satisfied; and initiating a handover to a target cell if at least the QoE enforcement conditions are satisfied by the target cell.

[0164] Example 18. The method of claim 17, wherein the CHO configuration includes one or more radio execution conditions for one or more target cells associated with one or more target RAN nodes, and wherein the method further includes: determining whether the radio conditions for one or more target cells in the target cells satisfy the radio execution conditions; and initiating a handover to the target cell if both the radio execution conditions and the QoE execution conditions are satisfied by the target cell.

[0165] Example 19. A computer program product comprising program instructions that, when executed by a computing device, cause the computing device to: receive a reconfiguration message from a first radio access network (RAN) node serving the UE at a UE access layer (UE-AS) of a mobile communication system, the reconfiguration message including a conditional handover (CHO) configuration, the CHO configuration including one or more quality of experience (QoE) enforcement conditions for one or more target cells associated with one or more target network nodes; send a request to the UE application layer (UE APP) to verify whether the QoE enforcement conditions for one or more target cells are satisfied; receive a response from the UE APP layer indicating whether the QoE enforcement conditions for one or more target cells are satisfied; and, if at least one or more QoE enforcement conditions are satisfied by the target cells, initiate a handover to a target cell.

[0166] Example device Figure 9An apparatus according to some example embodiments is shown, which may include a user terminal 100. The apparatus may be configured to perform operations described herein, such as those described with reference to any disclosed process. The apparatus includes at least one processor 102 and at least one memory 104, the at least one memory being directly or closely connected to the processor. The memory 104 includes at least one random access memory (RAM) and at least one read-only memory (ROM). Computer program code (software) 105 is stored in the ROM. The apparatus may be connected to a transmitter (TX) and a receiver (RX). The apparatus may optionally be connected to a user interface (UI) for indicating the apparatus and / or for outputting data. At least one processor 102 having at least one memory 104 and computer program code 105 is arranged to cause the apparatus to perform at least one method according to any of the foregoing processes, such as those disclosed regarding... Figures 2 to 8 Flowcharts and message sequences of its related characteristics.

[0167] Figure 10 A non-transitory medium 150 according to some embodiments is shown. The non-transitory medium 150 is a computer-readable storage medium. It may be, for example, a CD, DVD, USB stick, Blu-ray disc, etc. The non-transitory medium 150 stores computer program code, methods for causing a device to perform any of the aforementioned processes disclosed, such as flowcharts and related features.

[0168] The names of network elements, protocols, and methods are based on current standards. In other versions or other technologies, the names of these network elements and / or protocols and / or methods may differ, as long as they provide the corresponding functionality. For example, embodiments can be deployed in 2G / 3G / 4G / 5G networks and next-generation 3GPP networks, as well as in non-3GPP radio networks such as WiFi.

[0169] The memory can be volatile or non-volatile. It can be, for example, RAM, SRAM, flash memory, FPGA block RAM, DCD, CD, USB stick, and Blu-ray disc.

[0170] Unless otherwise stated or clearly understood from the context, two entities being distinct statements means that they perform different functions. This does not necessarily mean they are based on different hardware. That is, each entity described in this specification may be based on different hardware, or some or all of the entities may be based on the same hardware. This does not necessarily mean they are based on different software. That is, each entity described in this specification may be based on different software, or some or all of the entities may be based on the same software. Each entity described in this specification may be represented in the cloud.

[0171] Any implementation of the above-described boxes, apparatus, systems, techniques, or methods includes, as non-limiting examples, implementations as hardware, software, firmware, dedicated circuitry or logic, general-purpose hardware or controllers or other computing devices, or some combination thereof. Some embodiments may be implemented in the cloud.

[0172] It should be understood that the above content represents what is currently considered a preferred embodiment. However, it should be noted that the description of the preferred embodiment is given by way of example only, and various modifications may be made without departing from the scope defined by the appended claims.

Claims

1. A User Equipment Access Layer (UE-AS) layer for a mobile communication system, wherein the UE-AS comprises: At least one processor; as well as At least one memory, the at least one memory storing instructions, the instructions which, when executed by the at least one processor: A reconfiguration message is received from the first radio access network (RAN) node serving the UE. The reconfiguration message includes a conditional handover (CHO) configuration, which includes one or more quality of experience (QoE) execution conditions for one or more target cells associated with one or more target network nodes. Send a request to the UE's application layer (UE APP layer) to verify whether the QoE execution conditions for one or more target cells in the target cells are met; Receive a response from the UE APP layer, the response indicating whether the QoE conditions for one or more target cells in the target cells are met; as well as If at least the QoE execution conditions are met by the target cell, a handover to the target cell is initiated.

2. The UE-AS of claim 1, wherein the CHO configuration includes one or more radio execution conditions for the one or more target cells associated with one or more target RAN nodes, and wherein the instructions further cause the UE-AS to: Determine whether the radio conditions for one or more of the target cells satisfy the radio execution conditions; and If both the radio execution conditions and the QoE execution conditions are met by the target cell, a handover to the target cell is initiated.

3. The UE-AS according to claim 2, wherein the instruction further causes the UE-AS to at least: Determine the radio conditions for the one or more target cells.

4. The UE-AS according to any one of claims 1 to 3, wherein the request to the UE APP layer for verifying whether the QoE execution conditions are met includes an AT command.

5. The UE-AS according to any one of claims 1-3, wherein the instruction further causes the UE to at least: Provide radio measurements to the first RAN node.

6. The UE-AS according to any one of claims 1-3, wherein the QoE execution conditions are based on QoE measurements performed at a UE served by one or more target cells associated with one or more target RAN nodes.

7. The UE-AS according to any one of claims 1-3, wherein the QoE execution conditions for the one or more target cells in the target cells include at least a QoE threshold associated with one or more QoE metrics.

8. A user equipment (UE), comprising: At least one processor; as well as At least one memory, the at least one memory storing instructions, the instructions which, when executed by the at least one processor: A reconfiguration message is received from the first radio access network (RAN) node serving the UE. The reconfiguration message includes a conditional handover (CHO) configuration, which includes one or more quality of experience (QoE) execution conditions for one or more target cells associated with one or more target network nodes. Obtain an indication from the UE's application layer (UE APP layer) regarding whether the QoE execution conditions for one or more target cells in the target cells are met; as well as A handover to the target cell is initiated if at least the QoE execution conditions are met by one of the target cells.

9. The UE of claim 8, wherein the CHO configuration includes one or more radio execution conditions for the one or more target cells associated with one or more target RAN nodes, and wherein the instructions further cause the UE to: Determine whether the radio conditions for one or more of the target cells satisfy the radio execution conditions; and If both the radio execution conditions and the QoE execution conditions are met by the target cell, a handover to the target cell is initiated.

10. The UE of claim 9, wherein the instruction further causes the UE to at least: Determine the radio conditions for the one or more target cells.

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