Section: 21.5 Alignment of MDT and QoE Measurements
Content: The radio-related measurements may be collected via immediate MDT for all types of supported services for the purpose of QoE analysis. The MCE/TCE performs the correlation of the immediate MDT measurement results and the QoE measurement results collected at the same UE. The following is supported: - Alignment between a signalling-based QoE measurement and a signalling-based MDT measurement. In this case, the signalling-based QoE configuration sent to the gNB includes the NG-RAN Trace ID of the signalling-based MDT measurement. - Alignment between a management-based QoE measurement and a management-based MDT measurement. The UE configured with QoE measurements sends an indication to inform the gNB about the start or the stop of a QoE measurement session of configured QoE measurements. The gNB can activate the MDT measurements that are to be aligned with the QoE measurements performed by the UE upon/after receiving the QoE measurement session start indication from the UE. The gNB may activate the MDT measurements upon/after receiving the MDT activation message from the OAM. The gNB can deactivate the aligned MDT measurements according to an OAM command which may, e.g., be triggered by the session stop indication. The gNB includes time stamp information to the QoE measurement reports to enable the correlation of corresponding measurement results of MDT and QoE at the MCE/TCE. In addition, the gNB includes the MDT session identifiers (Trace Reference and Trace Recording Session Reference) in the corresponding QoE measurement report. 21.6 QoE Measurement Collection in High Mobility Scenarios QoE measurements can be confined to high mobility state of the UE and/or to HSDN cells. 21.7 Support for RAN visible QoE measurements and reporting in NR-DC Either the MN or the SN can generate and send a RAN visible QoE configuration to the UE. The gNB that has initially configured a UE in NR-DC with an RVQoE configuration can modify and release the RAN visible QoE configuration as long as the UE is connected to this gNB. The gNB that configures the encapsulated QoE measurements to UE is referred to as the RAN visible QoE-configuring gNB, and the peer node is referred to as the non-RAN visible QoE-configuring gNB. Upon mobility, the RAN visible QoE-configuring gNB may be changed. The UE may send RAN visible QoE reports to the network using either SRB4 or SRB5. In addition, the gNB that received a RAN visible QoE report can forward the report to the other gNB (the SN or the MN). QoE reports and RAN visible QoE reports pertaining to the same QoE Reference can be sent over the same SRB or they can be sent over different SRBs. The RAN visible QoE-configuring gNB can configure RAN visible QoE measurements at a UE without a priori knowledge about which gNB(s) will provide the bearer(s) for a future application session. During the lifetime of an application session, to ensure that the RAN visible QoE reports are sent to the gNB(s) that provide the bearer(s) which carry the data flow(s) associated with the RAN visible QoE measurement result in a RAN visible QoE report, the gNB receiving the RAN visible QoE reports determines the bearer(s) used to deliver the application session data flow(s) and the associated gNB (s). The determination may be based on the PDU session ID(s) and the QoS flow ID(s) indicated in a received RAN visible QoE report. When the RAN visible QoE-configuring gNB receives a RAN visible QoE measurement report and determines that the non-RAN Visible QoE-configuring gNB provides at least one bearer for the application session, the RAN Visible QoE-configuring gNB indicates that to the non-RAN Visible QoE-configuring gNB. The non-RAN Visible QoE-configuring gNB can then, if needed, indicate to the RAN visible QoE-configuring gNB its preference with respect to the reporting path for the subsequent RAN visible QoE reports and its preferred RAN visible QoE configuration parameters. If a gNB receives a RAN visible QoE report from a UE in NR-DC, and determines that the bearer(s) for the application session data flow(s) is (are) also provided by the other gNB, or only, provided by the other gNB, the gNB that received the RAN visible QoE measurement report may forward the received RAN visible QoE report to the other gNB. The RAN visible QoE reports can be transferred between the MN and the SN via the RRC TRANSFER message. The RAN visible QoE configuration may also be modified or released.