Managing quality of experience measurement in DC

Abstract

A user equipment (UE) communicates in dual connectivity (DC) with a master node (MN) via an MN link, and a secondary node (SN) via an SN link. The UE reports quality of experience (QoE) measurements toward the SN via the SN link; and in response to detecting a radio link failure (REF) on the SN link, the UE suspends the reporting of the QoE measurements via the SN link.

Description

MANAGING QUALITY OF EXPERIENCE MEASUREMENT IN DCCROSS-REFERENCE TO RELATED APPLICATION

[0001] This application claims priority to and the benefit of the filing date of provisional U.S. Patent Application No. 63 / 485,529, titled “Managing Quality of Experience Measurement in DC,” filed on February 16, 2023. The entire contents of the provisional application are hereby expressly incorporated herein by reference.FIELD OF THE DISCLOSURE

[0002] This disclosure relates to a wireless communications system, more particularly, to a wireless communications system that manages quality of experience measurement collection and reporting during mobility and / or state transition.BACKGROUND

[0003] In a wireless communication system, a base station that supports a certain Radio Access Technology (RAT) communicates with a user equipment (UE) using, among other protocols, a protocol for controlling radio resources corresponding to the RAT. The protocol for controlling radio resources may be, for example, a Radio Resource Control (RRC) protocol utilized by 4G, 5G, 6G, or later-generation wireless communication systems. Upon establishing a radio connection via the base station, the UE operates in a connected state of the protocol for controlling radio resources, which may be RAT-specific (e.g., EUTRA-RRC CONNECTED, NR-RRC CONNECTED).

[0004] Mobile networks evolve to improve the user experience. As such, the evaluation of the user experience at the UE side is useful to network operators. In particular, such evaluation is useful when operators provide real-time services which require, for example, high date rate and low latency, where even intermittent quality degradation may degrade a user’s experience. Such real-time services include streaming services (typically video services), Multimedia Telephony Service for Internet Multimedia Subsystem (IMS) (MTSI), Multicast and / or Broadcast Service (MBS), and / or extended reality (XR) services. Many of these services are a part of the commercial traffic growth rate, and therefore the focus is on the end user’s experience.

[0005] Generally speaking, Quality of Experience (QoE) measurement collection (QMC) provides detailed information for a UE, at a call (also called “application session”) level. Thesemeasurements can provide information which a network operator cannot derive based on RAN or CN measurements. A UE can collect QoE information and provide to a management system for analysis and / or key performance indicator (KPI) calculations.

[0006] In LTE systems, the QMC function enables collection of application layer measurements from the UE. The supported service types can include streaming services and MTSI services. A Trace Function from the Minimization of Drive Tests (MDT) framework activates the QMC. LTE supports signaling-based and management-based initiation cases. For the signaling-based case, the Application Layer Measurement Collection is initiated toward a specific UE from CN nodes using an MDT mechanism. For the management-based case, the Application Layer Measurement Collection is initiated from an operations, administration, and management (0AM) node targeting an area (without targeting a specific UE).

[0007] As described in 3GPP specifications 28.405 v!6.0.0, 36.300 v!6.6.0, and 36.331 V16.5.0, a transparent container encapsulates an application layer measurement configuration received from an 0AM node or CN, which a radio access network (RAN) forwards to a UE in a downlink RRC message. The RAN encapsulates application layer measurements received from the UE's higher layer in a transparent container and sends the measurements to the network in an uplink RRC message. The application layer measurement configuration and measurement reporting are supported in RRC CONNECTED state only. E-UTRAN can release the application layer measurement configuration toward the UE at any time.

[0008] It is not clear, however, how a UE and / or a network should support QoE measurement and reporting in certain mobility scenarios or failure scenarios (e g., radio link failure), especially when the UE operates in dual connectivity.SUMMARY

[0009] An example embodiment of the techniques of this disclosure is a method implemented in a user equipment (UE). The method comprises communicating in dual connectivity (DC) with a master node (MN) via an MN link, and a secondary node (SN) via an SN link; reporting quality of experience (QoE) measurements toward the SN via the SN link; and in response to detecting a radio link failure (RLF) on the SN link, suspending the reporting of the QoE measurements via the SN link.

[0010] Another example embodiment of these techniques is a method implemented in a first radio access network (RAN) node. The method comprises providing a master node (MN) link to a user equipment (UE) communicating in dual connectivity with the first RAN node operating as an MN, and with a second RAN node that operates as a secondary node (SN) and provides an SN link, the UE reporting quality of experience (QoE) measurements toward the SN via the SN link; receiving, from the UE, an indication of a failure of the SN link; and transmitting, to the UE, an indication of whether the UE is to switch the reporting of the QoE measurements to the MN link.

[0011] Another example embodiment of these techniques is an apparatus comprising a transceiver and processing hardware, where the apparatus is configured to implement one of the methods above.BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Fig. 1 A is a block diagram of an example system in which a base station and / or a user equipment (UE) can implement the techniques of this disclosure for managing quality of experience (QoE) measurement collection and reporting in a UE;

[0013] Fig. IB is a block diagram of an example base station including a central unit (CU) and a distributed unit (DU) that can operate in the system of Fig. 1A;

[0014] Fig. 2A is a block diagram of an example protocol stack according to which the UE of Figs. 1A-B can communicate with base stations;

[0015] Fig. 2B is a block diagram of an example protocol stack according to which the UE of Figs. 1A-B can communicate with one or more base stations using a distributed architecture;

[0016] Fig. 3A illustrates an example scenario in which the network configures a quality of experience (QoE) reporting toward an SN when the UE is in a dual connectivity (DC) mode;

[0017] Fig. 3B illustrates a scenario similar to that of Fig. 3 A, but in which the UE receives a QoE configuration from the MN or the SN;

[0018] Fig. 3C illustrates an example scenario in which the network configures QoE reporting toward an SN when the UE is in DC, and the SN determines to configure the UE with an SN QoE via an MN connection;

[0019] Fig. 3D illustrates a scenario similar to that of Fig. 3C, but in which the SN determines to configure the UE with a SN QoE via an SN connection;

[0020] Fig. 3E illustrates an example scenario in which the network configures QoE reporting toward an SN while the UE is in the standalone (SA) mode, and the UE reports toward an SN after receiving a QoE configuration from the MN;

[0021] Figs. 4A illustrates an example scenario in which a UE detects an RLF on the SN link and switches the reporting to the MCG leg, and switches back to the SCG leg upon recovering the SN connection;

[0022] Fig. 4B illustrates a scenario similar to that of Fig. 4A, but in which the UE cannot recover the SN connection and reconfigures the QoE reporting via the MCG leg;

[0023] Fig. 4B illustrates a scenario similar to that of Fig. 4A, but in which the UE cannot recover the SN connection and reconfigures the QoE reporting via the MCG leg;

[0024] Fig. 4C illustrates a scenario similar to that of Fig. 4A, but in which the UE recovers the SN connection and resumes the QoE collection ad reporting;

[0025] Fig. 4D illustrates a scenario similar to that of Fig. 4A, but in which the network releases the SN link;

[0026] Fig. 5A illustrates an example scenario in which a UE detects an RLF on the MN link, performs a fast MCG recovery, and resumes the SRB5;

[0027] Fig. 5B illustrates a scenario similar to that of Fig. 5 A, but in which the UE suspends a split SRB4 but does not suspend an SRB3;

[0028] Figs. 6A-C illustrate example scenarios in which the UE performs QoE measurement and reporting after an SN connection release or a secondary node change;

[0029] Fig. 7A is a flow diagram of an example method in which a UE receives a QoE configuration toward an SN via an MN link;

[0030] Fig. 7B is a flow diagram of an example method in which a UE receives a QoE configuration toward an SN via a SN link;

[0031] Fig. 8A is a flow diagram of an example method in which an MN receives a QoE configuration toward an SN and transmits a QoE configuration to a UE;

[0032] Fig. 8B is a flow diagram of an example method in which an MN receives a QoE configuration toward an SN and transmits a QoE configuration to an SN;

[0033] Fig. 8C is a flow diagram of an example method in which an MN receives a QoE measurement report toward an SN;

[0034] Fig. 8D is a flow diagram of an example method in which an MN receives a QoE configuration toward an SN while the UE is in standalone mode;

[0035] Fig. 8E is a flow diagram of an example method in which an SN receives a QoE configuration toward an SN and transmits a QoE configuration to an MN;

[0036] Fig. 8F is a flow diagram of an example method in which an SN receives a QoE configuration toward an SN and transmits a QoE configuration to UE;

[0037] Fig. 8G is a flow diagram of an example method in which an SN receives a QoE measurement report toward an SN;

[0038] Fig. 8H is a flow diagram of an example method in which an MN transmits the UE connection mode indication (DC or SA) to a CN or QAM;

[0039] Fig. 81 is a flow diagram of an example method in which aa CN / OAM receives the UE connection mode indication (DC) from an MN;

[0040] Fig. 8J is a flow diagram of an example method in which a CN / OAM receives the UE connection mode indication (SA) from an MN;

[0041] Fig. 9A is a flow diagram of an example method in which a UE detects an RLF on SN and switches the QoE measurement toward an SN from an SCG leg to an MCG leg;

[0042] Fig. 9B is a flow diagram of an example method in which a UE detects an RLF on an SN link and suspends the QoE measurement toward an SN;

[0043] Fig. 9C is a flow diagram of an example method in which a UE detects an RLF on an SN link and decides to suspend the QoE measurement toward an SN, and an SRB4 is not configured;

[0044] Fig. 9D is a flow diagram of an example method in which a UE detects an RLF on an SN and determines to suspend the QoE measurement toward SN, when the network does not allow to report QoE measurement report toward an SN via an MCG leg ;

[0045] Fig. 9E is a flow diagram of an example method in which an MN or SN indicates that QoE measurement report toward an SN via an MCG leg is allowed ;

[0046] Fig. 10 is a flow diagram of an example method in which a UE suspends split SRB4 or SRB5 for a QoE measurement report while performing fast MCG link recovery procedure;

[0047] Fig. 11 A is a flow diagram of an example method in which a UE receives an SCG release message and reconfigures the QoE measurement configuration toward an SN from an SN to an MN;

[0048] Fig. 1 IB is a flow diagram of an example method in which an MN determines to release an SN and reconfigure the QoE measurement configuration toward an SN from the SN to the MN;

[0049] Fig. 11C is a flow diagram of an example method in which an MN determines to release an SN and retain the QoE measurement configuration toward an SN by the SN;

[0050] Fig. 1 ID is a flow diagram of an example method in which a UE receives one or multiple message(s) from MN to release the SCG and maintain the QoE measurement report toward SN; and

[0051] Fig. 1 IE is a flow diagram of an example method in which an MN changes the secondary node of a UE and (re)configures QoE configuration toward SN from the SN to the MN.DETAILED DESCRIPTION

[0052] A UE, a source node of a RAN, a target node of a RAN, a core network, and / or an operations, administration, and management (0AM) node implement the techniques of this disclosure to manage QoE measurement and reporting during mobility and / or when a radio link failure occurs. As discussed in more detail below, a UE may receive commands to pause and / or resume QoE reporting during a handover process. Alternatively, the UE may autonomouslydetermine to pause and / or resume QoE reporting during a handover process. Further, the UE may receive multiple QoE configurations and operate QoE reporting accordingly. Still further, when the UE encounters a radio link failure, the UE in various implementations can suspend the measurement and reporting, continue the measurement or suspend the reporting, attempt a switch to another radio bearer, etc.

[0053] More specifically, a network node implements QMC and supports configuration and reporting for multiple simultaneous QoE measurements, for the same or different service types, for a UE. To identify the measurements and support activation, modification, and release functionality, a RAN node uses a mapping between reference IDs and QoE configurations. Further, the RAN in some cases can initiate pausing and resuming for one or more QoE configurations. More particularly, the RAN can the pause and resume functions in handover scenarios. The RAN also can support pausing and resuming initiated by a QoE node, such as the 0AM, during handover scenarios.

[0054] Referring first to Fig. 1A, an example wireless communication system 100 includes a UE 102, a source base station (S-BS) 104, a target base station (T-BS) 106, and a core network (CN) 110. The base stations 104 and 106 can operate in a RAN 105 connected to the core network (CN) 110. The CN 110 can be implemented as an evolved packet core (EPC) 111 or a fifth generation (5G) core (5GC) 160, for example. The CN 110 can also be implemented as a sixth generation (6G) core in another example.

[0055] The source base station 104 covers a cell 124, and the target base station 106 covers a cell 126. If the source base station 104 is a gNB, the cell 124 is an NR cell. If the base station 124 is an ng-eNB, the cell 124 is an evolved universal terrestrial radio access (E-UTRA) cell. Similarly, if the target base station 106 is a gNB, the cell 126 is an NR cell, and if the base station 126 is an ng-eNB, the cell 126 is an E-UTRA cell. The cells 124 and 126 can be in the same Radio Access Network Notification Areas (RNA) or different RNAs. In general, the RAN 105 can include any number of base stations, and each of the base stations can cover one, two, three, or any other suitable number of cells. The UE 102 can support at least a 5G NR (or simply, “NR”) or E-UTRA air interface to communicate with the base stations 104 and 106. Each of the base stations 104, 106 can connect to the CN 110 via an interface (e.g., SI or NGinterface). The base stations 104 and 106 also can be interconnected via an interface (e.g., X2 or Xn interface) for interconnecting NG RAN nodes.

[0056] Among other components, the EPC 111 can include a Serving Gateway (SGW) 112, a Mobility Management Entity (MME) 114, and a Packet Data Network Gateway (PGW) 116.The SGW 112 in general is configured to transfer user-plane packets related to audio calls, video calls, Internet traffic, etc., and the MME 114 is configured to manage authentication, registration, paging, and other related functions. The PGW 116 provides connectivity from the UE 102 to one or more external packet data networks, e.g., an Internet network and / or an Internet Protocol (IP) Multimedia Subsystem (IMS) network. The 5GC 160 includes a User Plane Function (UPF) 162 and an Access and Mobility Management Function (AMF) 164, and / or Session Management Function (SMF) 166. Generally speaking, the UPF 162 is configured to transfer user-plane packets related to audio calls, video calls, Internet traffic, etc.; the AMF 164 is configured to manage authentication, registration, paging, and other related functions; and the SMF 166 is configured to manage PDU sessions.

[0057] As illustrated in Fig. 1A, the source base station 104 supports a cell 124, and the target base station 106 supports a cell 126. The cells 124 and 126 can partially overlap, so that the UE 102 can select, reselect, or hand over from one of the cells 124 and 126 to the other. To directly exchange messages or information, the source base station 104 and target base station 106 can support an X2 or Xn interface. In general, the CN 110 can connect to any suitable number of base stations supporting NR cells and / or EUTRA cells.

[0058] Source base station 104 and UE 102 establish a connection via which the UE 102 and the source base station 104 transmit data payload, e.g., wirelessly. Upon establishing the connection via source base station 104, UE 102 is in a connected state of the RAT protocol for controlling radio resources (e.g., EUTRA-RRC CONNECTED, NR-RRC CONNECTED). Source base station 104 maintains a context of UE 102, where the context of the UE 102 includes configuration and other information associated with the connection of UE 102 with source base station 104. The context of UE 102 may include configurations of an SRB1, an SRB2, an SRB4, a DRB, and / or other configurations (e.g., security configuration) associated with the connection between UE 102 and source base station 104.

[0059] At some point in time, UE 102 establishes, resumes, or re-establishes a radio connection with target base station 106 for servicing. This may occur in various scenarios. In one scenario (“the handover scenario”), source base station 104 may determine that UE 102 is to handover to target base station 106. In another scenario (“the re-establishment scenario”), UE 102 may detect radio link failure (RLF) over the established connection with source base station 104 or detect integrity check failure on the SRB1, SRB2 or SRB4, and subsequently select target base station 106 for servicing. In yet another scenario (“the re-selection scenario”), source base station 104 may detect that below-threshold or no-data activity for UE 102 has occurred over some interval of time over the established connection. Upon this detection, source base station 104 instructs UE 102 to enter into an inactive state of the RAT protocol (e.g., EUTRA-RRC INACTIVE, NR-RRC INACTIVE). At some point in time thereafter, such as when UE 102 has moved into a different coverage area and has payload data to transmit to the system, UE 102 (which is in the inactive state) selects or reselects target base station 106 for servicing.

[0060] The source base station 104 is equipped with processing hardware 130 that can include one or more general-purpose processors (e.g., CPUs) and a non-transitory computer-readable memory storing instructions that the one or more general -purpose processors execute.Additionally or alternatively, the processing hardware 130 can include special-purpose processing units. The processing hardware 130 in an example implementation includes an RRC controller 132 to implement procedures and messaging at the RRC sublayer of the protocol communication stack. The processing hardware 130 can also include a QMC controller 134 configured to manage QoE configuration(s) and QoE reports for one or more UEs. The target base station 106 can include generally similar components. In particular, components 142 and 144 can be similar to the components 132 and 134, respectively.

[0061] The UE 102 is equipped with processing hardware 150 that can include one or more general-purpose processors such as CPUs and non-transitory computer-readable memory storing machine-readable instructions executable on the one or more general-purpose processors, and / or special-purpose processing units. The processing hardware 150 in an example implementation includes an RRC controller 152 to implement procedures and messaging at the RRC sublayer of the protocol communication stack. The processing hardware 150 can also include a QMC controller 154 configured to manage QoE configuration(s), QMC, and reporting.

[0062] Fig. IB depicts an example distributed or disaggregated implementation of any one or more of the base stations 104, 106. In this implementation, the source base station 104A, 104B, 106A, or 106B includes a central unit (CU) 172 and one or more DUs 174. The CU 172 includes processing hardware, such as one or more general-purpose processors (e.g., CPUs) and a computer-readable memory storing machine-readable instructions executable on the general- purpose processor(s), and / or special-purpose processing units. For example, the CU 172 can include a PDCP controller; an RRC controller; and / or a paging controller such as PDCP controller 134, 144; RRC controller 136, 146; and / or paging controller 138, 148. In some implementations, the CU 172 can include a radio link control (RLC) controller configured to manage or control one or more RLC operations or procedures. In other implementations, the CU 172 does not include an RLC controller.

[0063] Each of the DUs 174 also includes processing hardware that can include one or more general-purpose processors (e.g., CPUs) and computer-readable memory storing machine- readable instructions executable on the one or more general-purpose processors, and / or specialpurpose processing units. For example, the processing hardware can include a MAC controller (e.g., MAC controller 132, 142) configured to manage or control one or more MAC operations or procedures (e.g., a random access procedure), and / or an RLC controller configured to manage or control one or more RLC operations or procedures. The processing hardware can also include a physical layer controller configured to manage or control one or more physical layer operations or procedures.

[0064] In some implementations, the CU 172 can include a logical node CU-CP 172A that hosts the control plane part of the PDCP protocol of the CU 172. The CU 172 can also include logical node(s) CU-UP 172B that host the user plane part of the PDCP protocol and / or Service Data Adaptation Protocol (SDAP) protocol of the CU 172. The CU-CP 172A can transmit control information (e.g., RRC messages, Fl application protocol messages), and the CU-UP 172B can transmit the data packets (e.g., SDAP PDUs or Internet Protocol packets).

[0065] The CU-CP 172 A can connect to multiple CU-UP 172B through the El interface. The CU-CP 172A selects the appropriate CU-UP 172B for the requested services for the UE 102. In some implementations, a single CU-UP 172B can connect to multiple CU-CP 172A through the El interface. If the CU-CP and DU(s) belong to a gNB, the CU-CP 172A can connect to one ormore DU 174s through an Fl-C interface and / or an Fl-U interface. If the CU-CP and DU(s) belong to a ng-eNB, the CU-CP 172A can connect to one or more DU 174s through a Wl-C interface and / or a Wl-U interface. In some implementations, one DU 174 can connect to multiple CU-UPs 172B under the control of the same CU-CP 172A. In such implementations, the CU-CP 172A establishes the connectivity between a CU-UP 172B and a DU 174 using Bearer Context Management functions.

[0066] Fig. 2A illustrates, in a simplified manner, an example protocol stack 200 according to which the UE 102 can communicate with an eNB / ng-eNB or a gNB (e.g., one or more of the base stations 104, 106).

[0067] In the example stack 200, a physical layer (PHY) 202A of EUTRA provides transport channels to the EUTRA MAC sublayer 204A, which in turn provides logical channels to the EUTRA RLC sublayer 206A. The EUTRA REC sublayer 206A in turn provides RLC channels to a EUTRA PDCP sublayer 208 and, in some cases, to an NR PDCP sublayer 210. Similarly, the NR PHY 202B provides transport channels to the NR MAC sublayer 204B, which in turn provides logical channels to the NR RLC sublayer 206B. The NR RLC sublayer 206B in turn provides data transfer services to the NR PDCP sublayer 210. The NR PDCP sublayer 210 in turn can provide data transfer services to Service Data Adaptation Protocol (SDAP) 212 or a radio resource control (RRC) sublayer (not shown in Fig. 2A). The UE 102, in some implementations, supports both the EUTRA and the NR stack, as shown in Fig. 2A, to support handover between EUTRA and NR base stations and / or to support DC over EUTRA and NR interfaces. Further, as illustrated in Fig. 2A, the UE 102 can support layering of NR PDCP 210 over EUTRA RLC 206A, and SDAP sublayer 212 over the NR PDCP sublayer 210.

[0068] The EUTRA PDCP sublayer 208 and the NR PDCP sublayer 210 receive packets (e.g., from an Internet Protocol (IP) layer, layered directly or indirectly over the PDCP layer 208 or 210) that can be referred to as service data units (SDUs), and output packets (e.g., to the RLC layer 206A or 206B) that can be referred to as protocol data units (PDUs). Except where the difference between SDUs and PDUs is relevant, this disclosure for simplicity refers to both SDUs and PDUs as “packets.”

[0069] On a control plane, the EUTRA PDCP sublayer 208 and the NR PDCP sublayer 210 can provide signaling radio bearers (SRBs) or an RRC sublayer (not shown in Fig. 2) toexchange RRC messages or non-access-stratum (NAS) messages, for example. On a user plane, the EUTRA PDCP sublayer 208 and the NR PDCP sublayer 210 can provide data radio bearers (DRBs) to support data exchange. Data exchanged on the NR PDCP sublayer 210 can be SDAP PDUs, Internet Protocol (IP) packets, or Ethernet packets.

[0070] Thus, it is possible to functionally split the radio protocol stack, as shown by the radio protocol stack 250 in Fig. 2B. The CU can hold all the control and upper layer functionalities (e.g., RRC 214, SDAP 212, NR PDCP 210), while the lower layer operations (e.g, NR RLC 206B, NR MAC 204B, and NR PHY 202B) are delegated to the DU 174. To support connection to a 5GC, NR PDCP 210 provides SRBs to RRC 214, and NR PDCP 210 provides DRBs to SDAP 212 and SRBs to RRC 214.

[0071] Figs. 3A-3E are message sequences of example scenarios in which a SN Quality of Experience (QoE) measurement collection (QMC) and reporting for a UE in DC. Generally speaking, equivalent events in Figs. 3A-3E are labeled with similar reference numbers (e.g., event 306 in Fig. 3A is similar to event 306 in Figs. 3B-3E) with differences discussed below where appropriate. With the exception of the differences shown in the figures and discussed below, any of the alternative implementations discussed with respect to a particular event (e.g., for messaging and processing) may apply to events labeled with similar reference numbers in other figures and also to both integrated and distributed base stations.

[0072] Referring first to Fig 3A, in a scenario 300A, the UE initially operates 302 in a dual connectivity mode with a main base station 104 of a RAN 105 and a secondary base station 106 of a RAN 105. While the UE is in the DC mode or entering the DC mode, the MN 102 communicates with CN 110 / OAM 180 and transmits 304 a UE connection mode indication, to indicate the UE is in the DC mode. The CN 110 / an 0AM 180 then determines 306 to configure the UE 102 with a QoE configuration(s) toward the SN 106. The CN 110 / OAM 180 transmits 308 to the main base station 104 a command to activate QMC and reporting for the UE 102. Depending on the implementation, the QMC activation command may also include a particular reference identifier, such as a reference ID, identifying the QoE configuration. In implementations in which the QMC does not include a particular reference ID, the Trace ID may be used to identify the QoE configuration. In other implementations, the CN 110 / 0AM 180 transmits the one or more QoE configurations and / or any other information elements describedabove to the main base station 104 while communicating 308 with the main base station 104 and the UE 102.

[0073] In some implementations, the QMC activation is a Trace Start message (e.g., as defined in TS 32.421). In further implementations, the QMC activation command is included in an OAM-to-BS message or a CN-to-BS message, such as a next generation application protocol (NGAP) message. The CN 110 / OAM 180 may transmit 308 the CN-to-BS message or OAM-to- BS message, respectively, including the QMC activation command to the main base station 104. Depending on the implementation, the activation command includes, one or more QoE configurations, configuration identifiers (i.e., configuration IDs), reference identifiers (i.e., reference IDs), Trace IDs, Interfaces to Trace IE, Trace Depth IE, TCE IP Address (i.e., qoEReference), UE address (i.e., qoEC ollectionEntity Address)', an indication of the QMC activation and / or pause status, and / or the TCE URI as interface IES in the activation command, (e.g., as defined in TS 32.421). Depending on the implementation, variables and functions with similar features may be named differently. In some implementations, the activation command includes IEs describing area information (i.e., areaScope). In implementations in which the QMC activation command includes more than one QoE configuration, the CN 110 or 0AM 180 includes particular reference IDs for the QoE configurations in the QMC activation command. Depending on the implementation, the reference IDs may have the same or different values.

[0074] In some implementations, the one or more QoE configurations are associated with the first Trace ID. In other implementations, the CN 110 or 0AM 180 includes additional Trace IDs for additional QoE configurations beyond the first QoE configuration in the QMC activation command. Depending on the implementation, there may be an additional Trace ID for each of the additional QoE configurations, or multiple QoE configurations may be associated with a single Trace ID. The CN 110 or 0AM 180 can generate each Trace ID with a different value.

[0075] The main base station 104 then transmits 310 a message to the UE 102 to reconfigure radio resources for the UE 102, such as an RRC reconfiguration message. The UE 102 can transmit a “complete” message to the main base station 104, such as an RRC reconfiguration complete message (not shown), in response to the message 310. In some implementations, the main base station 104 generates a QoE configuration identifier, such as a QoE configuration ID, associated with the first QoE configuration and / or the first reference ID. The main base station104 can also generate a particular QoE configuration ID for each of the QoE configurations and / or reference IDs. In further implementations, the main base station 104 includes the one or more QoE configurations in the reconfiguration message. In other implementations, the main base station 104 may transmit the one or more QoE configurations to the UE 102 while communicating 306 with the UE 102, secondary base station 106 and CN 110. In response to receiving 310 the reconfiguration message, the UE 102 starts 318 QMC (QoE Measurement Collection) and reporting. Depending on the implementation, the UE 102 may begin transmitting 320 uplink (UL) message(s) to the main base station 104, the message(s) containing one or more QoE reports. In some implementations, the uplink message(s) are UL RRC messages. The main base station 104 may then transmit 322 the one or more QoE reports to the Trace Collection Entity (TCE) and / or Multi-cell / Multicast Coordination Entity (MCE) 190. Depending on the implementation, the QoE report(s) may be encapsulated in transparent container(s) that the main base station 104 receives 320 from the UE 102 and forwards to the CN 110 or 0AM 180. In further implementations, the UE 102 transmits 320 the QoE report(s) on a periodic basis. In other implementations, the UE 102 transmits 320 the QoE report(s) in response to particular and / or predefined triggering events. The main base station 104 may immediately transmit 322 any received 320 QoE report(s) to the CN 110 or 0AM 180. In other implementations, the main base station 104 aggregates the QoE reports before sending a message including the QoE reports to the CN 110 or 0AM 180. In yet other implementations, the main base station 104 aggregates the QoE reports with QoE reports from other UE(s) before sending a message including the QoE reports to the CN 110 or 0AM 180.

[0076] In one implementation, the CN 110 or an 0AM node 180 transmits 312 to the secondary base station 106 a command to activate QMC and reporting for the UE 102 instead of transmitting 308 a command to the main base station. The secondary base station 106 then transmits 314 a message to the main base station 104 to reconfigure radio resources for the UE 102. The main base station 104 transmits 316 a message to the UE 102 to reconfigure radio resources for the UE 102, such as an RRC reconfiguration message. In response to receiving 314 the reconfiguration message, the UE 102 starts 318 QMC and reporting. Depending on the implementation, the UE 102 may begin transmitting 324 uplink (UL) message(s) to the main base station 104, and the message(s) can contain one or more QoE reports. In some implementations, the uplink message(s) are UL RRC messages. The main base station 104 maythen transmits 326 the one or more QoE reports to the secondary base station 106. In one implementation, the UE 102 encapsulate the UL RRC message for SN (e.g., the QoE report) in the UL RRC message to MN. After this, the secondary base station 106 then transmit 328 the one or more QoE reports to the Trace Collection Entity (TCE) and / or Multi-cell / Multicast Coordination Entity (MCE) 190.

[0077] In one implementation, the CN 110 or an 0AM node 180 transmits 308 to the main base station and transmits 312 to the secondary base station 106 a command to activate QMC and reporting for the UE 102. In one implementation, the CN 110 or an 0AM node 180 transmits 312 to the secondary base station 106 while QoE configuration is for SN only. In another implementation, the CN 110 or an 0AM node 180 transmits 308 to the main base station 104 while QoE configuration is for both MN and SN.

[0078] In one implementation, the QoE configuration for MN is for a first application service (e.g., VR Service) and the QoE configuration for SN is for a second application service (e.g., MBS).

[0079] The events 324, 326, and 328 can be collectively referred to as a SN QoE reporting procedure 392. The events 302, 304, 306, 308, 310, 312, 314, 316, 318, 320, 322, 324, 326 and 328 can be collectively referred to as a SN QoE measurement configuration procedure 390.

[0080] Referring now to Fig. 3B, a scenario 300B is similar to 300A and similarly involves a CN 110 / OAM 180, main base station 104, secondary base station 106, and UE 102 activating QMC and reporting for the SN. However, here the secondary base station 106 may transmit the QoE configuration to the UE 102 directly and receive the QoE measurement report from the UE 102 also directly.

[0081] After determining to configure UE a QoE configure(s) 106, the CN 110 or 0AM 180 transmits 312 a QMC activation message to the secondary base station 106. The CN 110 or 0AM 180 includes a command to modify the one or more QoE configurations in the QMC activation message. The secondary base station 106 transmits 315 a radio resource reconfiguration message (e.g., an RRC reconfiguration message) to the UE 102, the message including the command to modify the one or more QoE configurations. In one implementation, the message includes the radio bearer configuration for the QoE report (e.g., a SRB5 for QoEmeasurement report transmission). Upon receiving 315 the radio resource reconfiguration message, the UE 102 starts 318 QMC and reporting. Depending on the implementation, the UE 102 may begin transmitting 325 uplink (UL) message(s) to the secondary base station 106, the message! s) containing one or more QoE reports. In some implementations, the uplink message(s) are UL RRC messages. The secondary base station 106 then transmit 329 the one or more QoE reports to the Trace Collection Entity (TCE) and / or Multi-cell / Multicast Coordination Entity (MCE) 190. The events 325 and 327 are collectively referred to as a SN QoE reporting procedure 393. The events 320 and 322 are collectively referred to in Fig. 3B as a SN QoE reporting procedure 394. The events 302, 304, 306, 308, 310, 312, 315, 318, 320, 322, 325 and 327 are collectively referred to in Fig. 3B as a SN QoE measurement configuration procedure 390.

[0082] Referring now to Fig. 3C, a scenario 300C is similar to 300A and similarly involves a CN 110 / OAM 180, main base station 104, secondary base station 106, and UE 102 activating QMC and reporting for the SN. However, unlike scenario 300 A, the main base station 104 may transmit the SN interface message to the secondary base station 106 to indicate current QoE configuration.

[0083] After deciding to configure UE a QoE configure(s) 106, the CN 110 or 0AM 180 transmits 308 a QMC activation message to the main base station 104. The CN 110 or 0AM 180 includes a command to modify the one or more QoE configurations in the QMC activation message. The main base station 104 then transmits 313 a SN interface including the QoE configuration to the secondary base station 106. In response to this, the secondary base station 106 may transmits 314 a RRC Reconfiguration message to the main base station 104. The main base station 104 then transmits 316 a message to the UE 102 to reconfigure radio resources for the UE 102, such as an RRC reconfiguration message. Depending on the implementation, the main base station may transmit 316 a QoE configuration message to the UE 102 irrespective of the receiving of the response message 314.

[0084] The UE 102, main base station 104, secondary base station 106 and the TCE / MCE 190 performs the SN QoE reporting procedure 392 or 393 or 394. The events 302, 304, 306, 308, 313, 314, 316 and 318 are collectively referred to in Fig. 3C as a SN QoE measurement configuration procedure 390.

[0085] Referring now to Fig. 3D, a scenario 300D is similar to 300C and similarly involves a CN 110 / OAM 180, main base station 104, secondary base station 106, and UE 102 activating QMC and reporting for the SN. However, unlike scenario 300C, the secondary base station 106 transmits QoE configuration for the UE 102 by a SN link.

[0086] After deciding to configure UE a QoE configure(s) 106, the CN 110 or 0AM 180 transmits 308 a QMC activation message to the main base station 104. The CN 110 or 0AM 180 includes a command to modify the one or more QoE configurations in the QMC activation message. The main base station 104 then transmits 313 a SN interface including the QoE configuration to the secondary base station 106. In response to this, the secondary base station 106 may transmits 315 a message to the UE 102 to reconfigure radio resources for the UE 102, such as an RRC reconfiguration message.

[0087] The UE 102, main base station 104, secondary base station 106 and the TCE / MCE 190 performs the SN QoE reporting procedure 392 or 393. The events 302, 304, 306, 308, 313, 315 and 318 are collectively referred to in Fig. 3D as a SN QoE measurement configuration procedure 390.

[0088] Referring now to Fig. 3E, a scenario 300E is similar to 300A and similarly involves a CN 110 / OAM 180, main base station 104, secondary base station 106, and UE 102 activating QMC and reporting for the SN. However, unlike scenario 300A, the secondary base station 106 transmits QoE configuration for the UE 102 by a SN link.

[0089] Referring first to Fig 3E, in a scenario 300E, the UE initially operates 303 in a SA (standalone) mode with a main base station 104 of a RAN. While the UE is in the SA mode or entering the SA mode, the MN 102 communicates with CN 110 / OAM 180 and transmits 305 a UE connection mode indication to indicate the UE is in SA mode. The CN 110 / an 0AM 180 then decides 306 to configure UE a QoE configuration(s) toward SN. The CN 110 / OAM 180 then transmits 308 to the main base station 104 a command to activate QMC and reporting for the UE 102. Depending on the implementation, the QMC activation command may also include a particular reference identifier, such as a reference ID, identifying the QoE configuration. In implementations in which the QMC does not include a particular reference ID, the Trace ID may be used to identify the QoE configuration. In other implementations, the CN 110 / 0AM 180 transmits the one or more QoE configurations and / or any other information elements describedabove to the main base station 104 while communicating 308 with the main base station 104 and the UE 102.

[0090] In some implementations, the QMC activation is a Trace Start message (e.g., as defined in TS 32.421). In further implementations, the QMC activation command is included in an OAM-to-BS message or a CN-to-BS message, such as a next generation application protocol (NGAP) message. The CN 110 / OAM 180 may transmit 308 the CN-to-BS message or OAM-to- BS message, respectively, including the QMC activation command to the main base station 104. Depending on the implementation, the activation command includes, one or more QoE configurations, configuration identifiers (i.e., configuration IDs), reference identifiers (i.e., reference IDs), Trace IDs, Interfaces to Trace IE, Trace Depth IE, TCE IP Address (i.e., qoEReference), UE address (i.e., qoEC ollectionEntity Address)', an indication of the QMC activation and / or pause status, and / or the TCE URI as interface IES in the activation command, (e.g., as defined in TS 32.421). Depending on the implementation, variables and functions with similar features may be named differently. In some implementations, the activation command includes IEs describing area information (i.e., areaScope). In implementations in which the QMC activation command includes more than one QoE configuration, the CN 110 or 0AM 180 includes particular reference IDs for the QoE configurations in the QMC activation command. Depending on the implementation, the reference IDs may have the same or different values.

[0091] In some implementations, the one or more QoE configurations are associated with the first Trace ID. In other implementations, the CN 110 or 0AM 180 includes additional Trace IDs for additional QoE configurations beyond the first QoE configuration in the QMC activation command. Depending on the implementation, there may be an additional Trace ID for each of the additional QoE configurations, or multiple QoE configurations may be associated with a single Trace ID. The CN 110 or 0AM 180 can generate each Trace ID with a different value.

[0092] The main base station 104 then transmits 330 a SgNB Addition Request to a secondary base station 106. In response to this, the base station 106 transmits 332 a SgNB Addition Request Acknowledge to the main base station 104. The main base station then transmit 317 a RRC Reconfiguration message including SCG configuration and the QoE configuration toward SN to the UE 102. In some implementations, the main base station 104 may transmit multiple RRCReconfiguration message to the UE 102 to configure the SCG configuration and the QoE configuration.

[0093] The UE 102 can transmit a “complete” message to the main base station 104, such as an RRC reconfiguration complete message (not shown), in response to the message 317. In some implementations, the main base station 104 generates a QoE configuration identifier, such as a QoE configuration ID, associated with the first QoE configuration and / or the first reference ID. The main base station 104 can also generate a particular QoE configuration ID for each of the QoE configurations and / or reference IDs. In further implementations, the main base station 104 includes the one or more QoE configurations in the reconfiguration message. In other implementations, the main base station 104 may transmit the one or more QoE configurations to the UE 102 while communicating 306 with the UE 102, secondary base station 106 and CN 1 10. In response to receiving 317 the reconfiguration message, the UE 102 starts 318 QMC (QoE Measurement Collection) and reporting and entering 302 a DC mode with main base station 104 and the secondary base station 106. In response to the UE in DC mode, the MN 102 communicates with CN 110 / OAM 180 and transmits 304 a UE connection mode indication to indicate the UE is in DC mode. The UE 102, main base station 104, secondary base station 106 and the TCE / MCE 190 then performs the SN QoE reporting procedure 392 or 393.

[0094] Next. Figs. 4A-4D are message sequences of example scenarios in which a UE detects a radio link failure on SN while a SN Quality of Experience (QoE) measurement collection (QMC) and reporting for a UE in DC. Generally speaking, equivalent events in Figs. 4A-4D are labeled with similar reference numbers (e.g., event 432 in Fig. 4A is similar to event 432 in Figs. 4B-4D) with differences discussed below where appropriate. With the exception of the differences shown in the figures and discussed below, any of the alternative implementations discussed with respect to a particular event (e.g., for messaging and processing) may apply to events labeled with similar reference numbers in other figures and also to both integrated and distributed base stations.

[0095] Referring first to Fig 4A, in a scenario 400A, the UE initially performs 490 a SN QoE measurement report configuration procedure, which is similar to the 390 SN QoE measurement report configuration procedure in Figs 3A-3D. The UE then 102 detects 432 a RLF between UE and SN. In response to the RLF, the UE 102 transmits 434 a SCGFailurelnformation message tothe MN 104 and switches 436 the QoE measurement collection / report toward SN form the SCG leg to the MCG leg. The UE then performs 492 SN QoE reporting procedure. In one implementation, the QoE report toward SN is switched from SRB5 to SRB4. In another implementation, the QoE report toward SN is switched from SN split SRB4 to MN split SRB4. In some implementation, the UE includes current QoE configuration or QoE report or QoE report available indication in the SCGFailurelnformation message.

[0096] In response to the SCGFailurelnformation, the MN decides 438 keep the SN and transmits 442 a RRC Reconfiguration message including at least a SCG configuration (e.g., a ReconfigurationWithSync field for SCG or a scecondaryCellGroup field) to the UE 102 to recover the SN link. The UE 102 then 444 applies the SCG configuration and recover the SN connection (e.g., applies the rach configuration from SCG configuration and perform the rach procedure to synch the SN again). In response to the SN connection recovery, the UE 102 switches 448 the QoE measurement collection / report toward SN form the MCG leg to the SCG leg. The UE then performs 493 SN QoE reporting procedure.

[0097] In one implementation, the MN 104 may decide to keep SN connection but does not switch the QoE report from MCG leg to SCG leg. In response to this decision, the MN then includes a specific field (e.g., release SRB5 or release SCG split SRB4) in 442 the RRCReconfiguration message to request this.

[0098] Referring now to Fig. 4B, a scenario 400B is similar to 400A and similarly involves a CN 110 / OAM 180, main base station 104, secondary base station 106, and UE 102 activating QMC and reporting forward the SN. However, unlike scenario 400A, the MN 104 decides to release SN after the SN link failure.

[0099] After receiving 434 the SCGFailurelnformation from the UE 102, the MN 104 decides 439 to release the SN connection between the UE 102 and the SN 106. In response to this decision, the MN 104 transmits 460 a SgNB Release Request message to the SN 106. The SN 106 then transmits 462 a SgNB Release Request Acknowledge message to the MN 104. In response to the SN release, the MN then transmits 443 a RRCReconfiguration message including SCG release field to the UE 102 and / or transmits 405 a UE connection mode indication with SA field to the CN 110 or 0AM 180. In response to the RRCReconfiguration message, the UE 102 releases 445 the SN connection and keeps 449 the QoE measurement collection / report forwardSCG via MCG leg. In one implementation, the CN 110 or 0AM 180 transmits 408 a QMC activation message to the MN 104 in response to the UE connection mode indication. The MN 104 then transmits 444 a RRCReconfiugraiton including QoE configuration to the UE 102. The UE 102 then (re)configures 449 the QoE measurement collection / report toward SN via MCG leg. The UE then performs 494 SN QoE reporting procedure.

[0100] In one implementation, the SN 106 transmits 464 SN Status Transfer or 466 DATA Forwarding or 468 Secondary RAT Data Usage Report to the MN 104 in response to the SN release. The MN 104 or SN 106 or CN110 or 0AM 180 then perform 470 a Path Update Procedure to update the SCG path to the MCG path in response to the SN release. After path update, the MN 104 tranmits 472 a UE Context Release message to the SN 106.

[0101] In some implementations, the UE 102 includes a specific filed in the SCGFailurelnformation to indicate it prefer to report QoE via MCG leg. In response to the preference, the MN 104 decides to release SN. In another implementation, the MN 104 decides to release SN due to it is unable to recover the SN link (e.g., the SN overload or MN lose connection with SN).

[0102] The events 439, 460, 462, 443, 405, 408, 444, 464, 466, 468, 470, 472 and 449 are collectively referred to in Fig. 4B as a MN initiate SN release and reconfigure QoE procedure 480.

[0103] Referring now to Fig. 4C, a scenario 400C is similar to 400A and similarly involves a CN 110 / OAM 180, main base station 104, secondary base station 106, and UE 102 activating QMC and reporting forward the SN. However, unlike scenario 400A, the UE 102 suspend the QoE measurement collection / report toward SN after the RLF on SN.

[0104] In response to the REF on the SN, the UE 102 suspends 437 the QoE measurement collection / report toward SN. In one implementation, the UE 102 suspends the QoE measurement report toward SN and does not suspend the QoE measurement collection toward SN. The MN then decides 438 keep the SN and transmits 442 a RRCReconfiguration message including at least a SCG configuration to the UE 102 to recover the SN link. The UE 102 then 444 applies the SCG configuration and recover the SN connection. In response to the SN connection recovery,the UE 102 resumes 450 the QoE measurement collection / report toward SN. The UE then performs 492 or 493 SN QoE reporting procedure.

[0105] In one implementation, the UE 102 decides to suspend the QoE measurement collection / report toward SN while the UE is not configured with QoE configuration forward MN (e.g., is not configured with SRB4 to transmit the QoE measurement report forward MN). In another implementation, the UE 102 decides to switch the QoE measurement from the SCG leg to MCG leg while it is configured with QoE configuration forward MN.

[0106] Referring now to Fig. 4D, a scenario 400D is similar to 400C and similarly involves a CN 110 / QAM 180, main base station 104, secondary base station 106, and UE 102 activating QMC and reporting forward the SN. However, unlike scenario 400C, the MN 104 decides to release SN after the SN link failure.

[0107] After the SN radio link failure, the UE 102, MN 104, SN 106, CN110 or 0AM 180 perform a 480 MN initiate SN Release and reconfigure QoE procedure to (re)configure the QoE measurement collection / report forward MN. The UE 102 then performs 494 SN QoE reporting procedure.

[0108] Referring now to Fig 5A, in a scenario 500 A, the UE initially performs 590 a SN QoE measurement report configuration procedure, which is similar to the 390 SN QoE measurement report configuration procedure in Figs 3A-3D. The UE then 102 detects 532 a RLF between UE and MN. In response to the RLF, the UE 102 then 534 suspends SRB5, 536 does not suspend SRB3 and performs 538 Fast MCG link recovery with MN 104 and SN 106. After the MCG link recovery, the UE 102 resumes SRB5. The UE then performs 592 or 593 SN QoE reporting procedure, which is similar to the 392 and 393 SN QoE reporting procedure.

[0109] Referring next to Fig. 5B, a scenario 500B is similar to 500A and similarly involves a CN 110 / OAM 180, main base station 104, secondary base station 106, and UE 102 activating QMC and reporting forward the SN. However, unlike scenario 500A, the UE suspends split SRB4 for QoE report toward SN after the RLF on SN and resumes split SRB4 for QoE report toward SN after the radio link recovery on SN.

[0110] the UE 102, MN transmits 434 a SCGFailurelnformation message to the MN 104 and switches 436 the QoE measurement collection / report toward SN form the SCG leg to the MCGleg. The UE then performs 492 SN QoE reporting procedure. In one implementation, the QoE report toward SN is switched from SRB5 to SRB4. In another implementation, the QoE report toward SN is switched from SN split SRB4 to MN split SRB4. In some implementations, the UE includes current QoE configuration or QoE report or QoE report available indication in the SCGFailurelnformation message.[0U1] Referring now to Fig 6A, in a scenario 600 A, the UE initially performs 690 a SN QoE measurement report configuration procedure, which is similar to the 390 SN QoE measurement report configuration procedure in Figs 3A-3D. The SN 106 decides 641to release the SN connection between the SN 106 and the UE 102. In response to this decision, the SN 106 transmits 661 a SgNB Release Request to the MN 104. The MN 104 then transmits 663 SgNB Release Request Acknowledge to the SN 106. Then the UE 102, MN 104, SN 106, CN110 and 0AM 180 performs event 642, 605, 608, 645, 644, 664, 666, 668, 670, 672 and 649, which is similar to the event 442, 405, 408, 445, 444, 464, 466, 468, 470, 472 and 449 in Fig 4B. The UE 102 then performs 694 MN QoE reporting procedure, which is similar to 394 SN QoE reporting procedure. In some implementations, the SN connection release is decided by MN 104 instead of decided by SN 106.

[0112] The events 641, 661, 663, 642, 605, 608, 645, 644, 664, 666, 668, 670, 672 and 649 are collectively referred to in Fig. 6A as a SN initiate SN Release and QoE reconfiguration procedure.

[0113] Referring now to Fig 6B, in a scenario 600B, the UE initially performs 690 a SN QoE measurement report configuration procedure, which is similar to the 390 SN QoE measurement report configuration procedure in Figs 3A-3D. The MN 104 decides 640 to change UE’s secondary node from SN 106 to T-SN 106B. In response to this decision, the MN 104 transmits 646 a SgNB Addition Request message to the T-SN 106B. The T-SN 106B then transmits 648 a SgNB Addition Request Acknowledge message to the MN 104. After receiving the Acknowledge from T-SN 106B, the MN 104 transmits 652 a SgNB Release Request message to SN 106 and transmits 654 a RRC reconfiguration message including SCG configuration to the UE 102. The SN 106 then transmits 652 a SgNB Release Request Acknowledge message to the MN 104 to response the SgNB Release Request message. In one implementation, the change of secondary node may decide by SN 106. The SN 106 then transmits a SgNB change requiredmessage to MN 104. In response to the SgNB change required message, the MN 104 may transmit 646 SfNB Addition Request message to the T-SN 106B.

[0114] The UE 102 then transmits 676 a RRC Reconfiguration Complete message to the MN 104, in response to the message 654. The UE 102 then continuously 662 collect the QoE data toward SN and suspend the QoE report toward SN. In one implementation, the MN 104 may request UE 102 to release the QoE configuration toward SN by 654 RRC reconfiguration message (e.g., include a SCG QoE release field). In another implementation, the MN 104 may request UE 102 to continuously collect the QoE data toward SN and suspend the QoE report toward SN by 654 RRC reconfiguration message.

[0115] After receiving the RRC Reconfiguration Complete message, the MN 104 transmits 656 a SgNB Reconfiguration Complete message to the SN 106 and transmits 604 a UE connection mode indication message to the CN 110 or 0AM 180 to indicate the UE 102 is in DC with T-SN. In response to the UE connection mode indication, the CN 110 or 0AM 180 may decide 606 to configure QoE configuration(s). The CN 110 or 0AM 180 then transmits 609 a QMC activation include QoE configuration to the T-SN 106B. The T-SN 106B then transmits a RRC reconfiguration message to the UE 102 to configure the QoE configuration forward T-SN. After receiving the 655 RRC reconfiguration message from MN 104, the UE 102 stops 674 the QoE data collection toward SN and / or discards the QoE report(s) toward SN. The UE 102 then applies 664 the new QoE configuration and start the QoE measurement collection / report forward T-SN. In one implementation, the UE 102 transmits the QoE report(s) toward SN to the MN 104 or T-SN 106B before it discard the report(s) (e.g., by a RRC reconfiguration complete message or a measurement report message by SRB4 or SRB5). The UE then performs 692 or 693 SN QoE reporting procedure, which is similar to 392 or 393.

[0116] In one implementation, the T-SN 106B may transmits the QoE configuration to the MN 104 after it receives the QoE configuration from QMC activation, which is similar to the 314. In another implement, the CN 110 or 0AM 180 may transmit the QMC activation including the QoE configuration to the MN 104 instead of transmits it to the T-SN 106B, which is similar to 308. After receiving the QoE configuration from T-SN 106B or CN 110 or 0AM 180, the MN 104 transmit a RRC reconfiguration message to the UE 102 to configure the QoE configuration, which is similar to 310 or 316.

[0117] In some implementations, the UE 102 switches the QoE measurement collect! on / report toward SN form SCG leg to the MCG leg instead of performs event 662 after it receives 654 the RRC reconfiguration message from the MN 104.

[0118] Referring next to Fig. 6C, a scenario 600C is similar to 600B and similarly involves a CN 110 / OAM 180, main base station 104, secondary base station 106, a target secondary base station 106B and UE 102 activating QMC and reporting forward the SN. However, unlike scenario 600B, the CN 110 or 0AM 180 decide to (re)configure the QoE measurement from SN to MN after the PSCell change.

[0119] After the PSCell change from SN 106 to T-SN 106B, the CN 110 or 0AM decides 606 to configure a QoE configuration. In response to this decision, the CN 110 or 0AM 180 transmits 608 a QMC activation including QoE configuration to the MN 104. The MN 104 then transmit 655 a RRC reconfiguration message including QoE configuration forward MN to the UE 102. After receiving the 655 RRC reconfiguration message from MN 104, the UE 102 stops 674 the QoE data collection toward SN and / or discards the QoE report(s) toward SN. The UE 102 then applies 665 the new QoE configuration and start the QoE measurement collection / report forward MN. In one implementation, the UE 102 transmits the QoE report(s) toward SN to the MN 104 before it discard the report(s) (e.g., by a RRC reconfiguration complete message or a measurement report message by SRB4 or SRB5). The UE 102 then performs MN QoE reporting procedure 694, which is similar to SN QoE reporting procedure 394.

[0120] Referring now to Fig. 7A, a method 700A can be implemented in a suitable UE and, generally speaking, involves receiving a command to collect QoE data and subsequently reporting the QoE data toward the SN. For clarity, the method 700A is discussed with reference to the RAN 105 and the UE 102.

[0121] At block 702, the UE 102 communicates with a RAN 105 and receives a QoE configuration toward the SN from the MN (e.g., event 310 or 316 of Figs. 3A-3C, 3E). At block 704, the UE 102 starts QoE measurement collection and reporting toward the SN (e.g., event 318 of Figs. 3A-3C, 3E). Then, at block 706, the UE 102 transmits a QoE measurement report toward the SN to the MN (e.g., event 320 or 324 of Figs. 3A-3C, 3E).

[0122] Referring now to Fig. 7B, a method 700B is generally similar to the method 700A, but here the UE 102 receives the QoE configuration from the SN and reports the QoE report to the SN. More specifically, the differences between the methods of Fig. 7A and Fig. 7B are discussed below.

[0123] At block 703, the UE 102 communicates with a RAN 105 and receive a QoE configuration toward SN from the SN (e.g., event 315 of Figs. 3D). At block 704, the UE 102 starts a QoE measurement collection and report toward SN (e.g., event 318 of Figs. 3D). Then, at block 707, the UE 102 transmits a QoE measurement report toward SN to the SN (e.g., event 325 of Figs. 3D).

[0124] For clarity, method 800A-J are discussed with specific reference to the RAN 105, the base station 104 as a main base station, the base station 106 as a secondary base station, the CN 110 or 0AM 180 as a QoE node (e.g., a network node), and the UE 102.

[0125] Referring now to Fig. 8A, a method 800A can be implemented in a main base station node of a suitable RAN, and includes receiving one or more QoE configurations, reference identifiers, configuration identifiers, and information on the association between reference identifiers and configuration identifiers for a secondary node. At block 808, the MN 104 communicates with the RAN 105 and receives a QoE configuration toward the SN from the SN 106 or CN 110 or 0AM 180 (e.g., event 308 or 314 of Figs. 3A-3C, 3E). At block 810, the MN 104 determines to configure the QoE configuration toward the SN via an MN link. Then, at block 812, the MN 104 transmits a QoE configuration to the UE 102 (e.g., event 310 or 316 of Figs. 3A-3C, 3E). In one implementation, the flow omits block 810, and the MN 104 transmits the received QoE configuration to the UE 102.

[0126] Referring now to Fig. 8B, a method 800B is generally similar to the method 800A, but here the MN 104 transmits the QoE configuration to the SN 106, and the QoE configuration is related to the SN. More specifically, the differences between the methods of Fig. 8 A and Fig. 8B are discussed below. At block 808, the MN 104 communicates with the RAN 105 and receives a QoE configuration toward the SN from CN 110 or 0AM 180 (e.g., event 308 of Figs. 3C, 3D). Then, at block 813, the MN 104 transmits the QoE configuration to the UE 102 (e.g., event 313 of Figs. 3C, 3D).

[0127] Referring now to Fig. 8C, a method 800C can be implemented in a main base station node of a suitable RAN, and includes receiving one or more QoE measurement report(s) toward a secondary base station. At block 814, the MN 104 communicates with a RAN 105 and receives a QoE measurement report toward the SN (e.g., event 320, 324 of Figs. 3A-3E). Then, at block 816, the MN 104 transmits the QoE configuration to the SN 106 or the TCE / MCE 190 (e.g., event 322 or 326 of Figs. 3A-3E).

[0128] Referring now to Fig. 8D, a method 800D can be implemented in a main base station node of a suitable RAN and includes receiving one or more QoE measurement report(s) toward a secondary base station in the standalone mode. At block 818, the MN 104 communicates with a RAN 105 and receives a QoE measurement configuration toward the SN (e.g., event 308 of Fig. 3E). At block 820, the MN 104 determines to configure UE 102 a QoE configuration toward SN and the SN connection between UE 102 and the SN 106. Then, at block 822, the MN 104 transmits a QoE configuration and the SCG configuration to the UE 102 (e.g., event 317 of Fig. 3E).

[0129] Referring now to Fig. 8E, a method 800E can be implemented in a secondary base station node of a suitable RAN, and includes receiving one or more QoE measurement report(s) toward a secondary base station. At block 824, the SN 106 communicates with the RAN 105 and receives a QoE measurement configuration toward the SN (e.g., event 312 or 313 of Figs. 3A, 3C). Then, at block 826, the SN 106 transmits the QoE configuration to the MN 104 (e.g., event 314 of Figs. 3 A, 3C).

[0130] Referring now to Fig. 8F, a method 800F is generally similar to the method 800E, but here the SN 106 transmits a QoE configuration to the UE 102. More specifically, at block 824, the SN 106 communicates with the RAN 105 and receives a QoE measurement configuration toward the SN (e.g., event 312 or 313 of Figs. 3B, 3D). Then, at block 827, the SN 106 transmits the QoE configuration to the UE 102 (e.g., event 315 of Figs. 3B, 3D).

[0131] Referring now to Fig. 8G, a method 800G can be implemented in a secondary base station node of a suitable RAN, and includes receiving one or more QoE measurement report(s) toward a secondary base station. At block 828, the SN 106 communicates with a RAN 105 and receives a QoE measurement report toward SN (e.g., event 325, 326 of Figs. 3A-3E). Then, atblock 830, the SN 106 transmits the QoE configuration to the TCE / MCE 190 (e.g., event 327 or 328 of Figs. 3A-3E).

[0132] Referring now to Fig. 8H, a method 800H can be implemented in a main base station node of a suitable RAN, and includes detecting the UE is has switched to the DC mode or the SA mode, and indicating the change to the CN 110 or 0AM 180. At block 832, the MN 104 communicates with the RAN 105 and detects that the UE 102 has switched to the DC or the SA mode. Then, at block 834, the MN 104 transmits an indication to the CN 110 or 0AM 180 to indicate the UE connection mode is now DC or SA (e.g., event 304 or 305 of Figs. 3A-3E). In one implementation, the MN indicates the UE connection mode to the CN 110 or 0AM 180 after the PCell change or the PSCell change.

[0133] Referring now to Fig. 81, a method 800K can be implemented in a CN 110 or 0AM 180, and includes receiving an indication that the UE 102 now operates in DC. At block 836, the CN 110 or 0AM 180 receives an indication that the UE is now in DC, from the MN 104 (e.g., event 304 of Figs. 3A-3D). At block 838, the CN 110 or 0AM 180 determines to configure the UE 102 with a QoE configuration (e.g., event 306 of Figs. 3A-3D). Then, at block 840, the MN 104 transmits a QMC activation message to the MN 104 or the SN 106 (e.g., event 308 or 312 of Figs. 3A-3D).

[0134] Referring now to Fig. 8J, a method 800J is generally similar to the method 800K, but here the CN 110 or 0AM 180 receives an indication that the UE is now in the SA mode. More specifically, at block 837, the CN 110 or 0AM 180 receives an indication that the UE 192 is in SA, from the MN 104 (e.g., event 305 of Fig. 3E). At block 838, the CN 110 or 0AM 180 determines to configure the UE 102 with a QoE configuration (e.g., event 306 of Figs. 3E). Then, at block 841, the MN 104 transmits a QMC activation message to the MN 104 (e.g., event 308 of Figs. 3E).

[0135] Referring now to Fig. 9A, a method 900A can be implemented in a suitable UE and includes performing a QoE measurement collection and reporting toward a secondary node and subsequently detecting a radio link failure on the secondary node. For clarity, the method 900A is discussed with reference to the RAN 105 and the UE 102.

[0136] At block 902, the UE 102 communicates with the RAN 105 and detects a radio link failure on the SN 104 (e.g., event 432 of Figs. 4A, 4B). At block 904, the UE 102 transmits an SCGFailurelnformation message to the MN 104 (e.g., event 434 of Figs. 4A, 4B). At block 906, the UE 102 switches the QoE measurement collection / reporting from the SCG leg to the MCG leg (e.g., event 436 of Figs. 4A, 4B). At block 908, the UE 102 successfully recovers the connection between UE 102 and the SN 106 (e.g., event 442 of Figs. 4A). Then, at block 910, UE 102 switches the QoE measurement collection / report from the MCG leg to the SCG leg (e.g., event 448 of Figs. 4A). At block 912, the UE 102 determines that it cannot recover the connection between UE 102 and the SN 106 (e.g., event 443 of Figs. 4B). Then, in block 914, the UE 102 retains the QoE measurement collection / reporting via the MCG leg (e.g., event 449 of Figs. 4B).

[0137] Referring now to Fig. 9B, a method 900B is generally similar to the method 900A, but here the UE 102 suspends the QoE measurement collection / reporting toward the SN 106. More specifically, at block 902, the UE 102 communicates with a RAN 105 and detects a radio link failure on the SN 106 (e.g., event 432 of Figs. 4C, 4D). At block 904, the UE 102 transmits an SCGFailurelnformation message to the MN 104 (e.g., event 434 of Figs. 4C, 4D). At block 907, the UE 102 suspends the QoE measurement collection / reporting toward the SN 104 (e.g., event 437 of Figs. 4C, 4D). At block 908, the UE 102 successfully recovers the connection between UE 102 and the SN 106 (e.g., event 442 of Figs. 4C). Then, at block 911, UE 102 resumes the QoE measurement collection / reporting (e.g., event 450 of Figs. 4C). At block 912, the UE 102 determines that it cannot recover the connection between the UE 102 and the SN 106 (e.g., event 443 of Figs. 4B). Then, at block 914, the UE 102 reconfigures the QoE measurement collection / report by MCG leg (e.g., event 449 of Fig. 4B).

[0138] Referring now to Fig. 9C, a method 900C is generally similar to the method 900B, but here the UE 102 determines whether to suspend the QoE measurement collection / reporting toward the SN 106 in view of the SRB4 configuration.

[0139] At block 902, the UE 102 communicates with the RAN 105 and detects a radio link failure on the SN 104 (e.g., event 432 of Figs. 4A-4D). At block 916, the UE 102 determines whether the UE 102 is configured with the SRB4 (i.e., the SRB for QoE reporting toward the MN). If yes, the flow proceeds to block 906, where the UE 102 switches the QoE measurementcollection / reporting from the SCG leg to the MCG leg (e.g., event 436 of Figs. 4A, 4B). Otherwise, the flow proceeds to block 907, where the UE suspends the QoE measurement collection / reporting toward the SN 104 (e.g., event 437 of Figs. 4C, 4D).

[0140] Referring now to Fig. 9D, a method 900D is generally similar to the method 900C, but here the UE 102 determines whether to suspend the QoE measurement collection / reporting toward the SN 106 in view of the network configuration. More specifically, At block 917, the UE 102 determines whether SN QoE reporting via anSRB4 is allowed . If so, the flow proceeds to block 906, where the UE 102 switches the QoE measurement collection / reporting from the SCG leg to the MCG leg (e.g., event 436 of Figs. 4A, 4B). Otherwise, the flow proceeds to block 907, where the UE 102 suspends the QoE measurement collection / reporting toward the SN 104 (e.g., event 437 of Figs. 4C, 4D).

[0141] In some implementations, the UE 102 switches the QoE measurement collection / reporting toward the SN from the SCG leg to the MCG leg, while is the UE 102 is allowed to report SN QoE measurements via anSRB4 and is configured with an SRB4.

[0142] Referring now to Fig. 9E, a method 900E can be implemented in a main base station of a suitable RAN or a secondary base station node of a suitable RAN, and includes receiving one or more QoE measurement report(s) toward a secondary base station. For clarity, the method 900E is discussed with specific reference to the RAN 105, the base station 104 as a main base station, the base station 106 as a secondary base station, the CN 110 or 0AM 180 as a QoE node (e.g., a network node), and the UE 102.

[0143] At block 918, the MN 104 or SN 106 communicates with a RAN 105 and determines to allow the UE to perform QoE measurement col lection / r eport toward the SN while the SN is experiencing an RLF. Then, at block 920, the MN 104 or SN 106 includes an indication in the QoE configuration message (e.g., the RRCReconfiguration message to configure QoE) or configures UE with a split SRB4. In one implementation, the MN 104 includes an indication in system information to indicate this configuration.

[0144] Referring now to Fig. 10, a method 1000 can be implemented in a suitable UE and includes performing a QoE measurement collection reporting toward a secondary node, andsubsequently detecting a radio link failure associated with the main node. For clarity, the method 1000 is discussed with specific reference to the RAN 105 and the UE 102.

[0145] At block 1002, the UE 102 communicates with theRAN 105 and detects a radio link failure on the link to the MN 104 (e.g., event 532 of Figs. 5 A, 5B). At block 1004, the UE 102 suspends the SRB5 or split SRB4 for QoE report transmission (e.g., event 534 of fig. 5A or event 535 of fig.5B). At block 1006, the UE 102 performs a fast MCG link recovery procedure (e.g., event 538 of Figs. 5A, 5B). Then, at block 1008, the UE 102 resumes the SRB5 or the split SRB4 for QoE report transmission (e.g., event 540 of fig. 5A or event 541 of fig.5B).

[0146] Referring now to Fig. 11 A, a method 1100A can be implemented in a suitable UE and includes receiving an SCG release message from a main base station and subsequently (re)configuring the QoE measurement collection / report toward a secondary node to a main node. For clarity, the method 1100A is discussed with specific reference to the RAN 105 and the UE 102.

[0147] At block 1102, the UE 102 communicates with a RAN 105 and receives an SCG release message (e.g., a RRCReconfiguration message includes SCG release field) from MN 104 (e.g., event 642 of Fig.6A). At block 1104, the UE 102 receives a QoE configuration from MN 104 (e.g., event 644 of Fig. 6A). Then, at block 1106, the UE 102 (re)configure the QoE measurement collection / report toward a secondary node to a main node 104 (e.g., event 649 of Fig. 6A). In one implementation, the UE 102 (re)configures the QoE measurement collection / reporting forward a secondary node to a main node immediately after receiving the SN release request from the MN 104, and thus block 1104 is optional block 1104.

[0148] Referring now to Fig. 1 IB, a method 1100B can be implemented in a main base station node of a suitable RAN, and includes determining to release the SN connection of a UE 102. For clarity, the method 1100B is discussed with reference to the RAN 105, the base station 104 as a main base station, the base station 106 as a secondary base station, the CN 110 or 0AM 180 as a QoE node (e.g., a network node), and the UE 102.

[0149] At block 1108, the MN 104 communicates with a RAN 105 and determines to release the SN connection of the UE 102 or receives the SgNB release request from the SN 104( e.g., event 641 of Fig.6A). Then, at block 1110, The MN 104 transmits an SCG release informationand a QoE configuration information to the UE 102 (e.g., event 642 or 644 of Fig. 6A). The MN 104 may include the SCG release information and the QoE configuration information in one or multiple messages (e.g., in one or multiple RRCReconfiguration message(s))

[0150] Referring now to Fig. 11C, a method 1100C is generally similar to the method 1100B, but here the MN 102 determines to keep (retain) the QoE report transmission via an SCG SRB.

[0151] At block 1108, the MN 104 communicates with a RAN 105 and decides to release the SN connection of the UE 102 or receives the SgNB release request from the SN 104. At block 1112, the MN 104 determines to keep QoE report transmission toward the SN via an SCG SRB (e.g., SRB5 or split SRB4). Then, at block 1114, the MN 104 transmits an SCG release information and a QoE configuration information to the UE 102 in one or more RRC message(s). The UE 102 connects with SN 106 using a split SRB4 or SRB5 only (i.e., there is no SRB3).

[0152] Referring now to Fig. 1 ID, a method HOOD can be implemented in a suitable UE and includes receiving, at block 1116, an SCG release message from a main base station and, at block 1118,(re)configuring the QoE measurement collection / report toward a secondary node.

[0153] Finally, Fig. 1 IE illustrates an example method in an MN, e.g., the MN 104. At block 1120, the MN 104 determines to change the secondary node of a UE or receives a SgNB change required message from SN 106 (e.g., event 640 of Figs. 6B, 6C). At block 1122, the MN 104 transmits an SgNB Addition Request message to a T-SN 106 (e.g., event 646 of Figs. 6B, 6C). At block 1124, the MN 104 transmits an SgNB Release request message to the SN 106 (e.g., event 650 of Figs. 6B, 6C). At block 1126, the MN 104 transmits an indication to the CN 110 or 0AM 180 to indicate the UE is in DC and change the secondary node to the T-SN 106B (e.g., event 604 of Figs. 6B, 6C). At block 1128, the MN 104 receives a QoE activation message from CN 110 or 0AM 180 (e.g., event 608 of Fig. 6C). Then, at block 1130, the MN 104 transmits a QoE configuration to the UE 102(e.g., event 655 of Figs. 6C).

[0154] The disclosure contemplates at least the following examples.

[0155] A method for managing quality of experience (QoE) reporting is implemented in a radio access network (RAN). The method includes facilitating, by processing hardware, reporting of QoE measurements for a user equipment (UE), to a QoE node; determining, by theprocessing hardware, to perform a handover of the UE from the source node to a target node in the RAN; and subsequently to the determining, transmitting a pause status for the reporting.

[0156] A method for managing QoE reporting is implemented in a source node in a RAN. The method includes facilitating, by processing hardware, reporting of QoE measurements to a QoE node according to a plurality of QoE configurations, for a UE; determining, by the processing hardware, to perform a handover of the UE from the source node to a target node in the RAN; and providing, by the processing hardware to the target node and in response to the determining, identification information to identify a QoE configuration within the plurality of QoE configurations.

[0157] A method for managing QoE reporting is implemented in a target node of a RAN. The method includes receiving, by the processing hardware, a plurality of QoE configurations associated with reporting QoE measurements to a QoE node from a UE; facilitating, by the processing hardware, a handover of the UE from a source node of the RAN to the target node according to the plurality of QoE configurations; and receiving, by the processing hardware at the target node and in response to the handover, identification information to identify a QoE configuration within the plurality of QoE configurations.

[0158] A method for managing QoE reporting is implemented in a UE. The method includes reporting, by processing hardware, QoE measurements to a QoE node via a RAN; receiving, by the processing hardware, a command to perform a handover from a source cell of the RAN to a target cell in the RAN; and determining, by the processing hardware, whether to pause the reporting during the handover, based on an indication received from the RAN.

[0159] A method for managing QoE reporting is implemented in a QoE node operating in, or in communication with, a core network (CN). The method includes receiving, by processing hardware, QoE measurements from a UE via a source node of a RAN; transmitting, by the processing hardware to the UE via the RAN, a command to change a pause status of reporting of the QoE measurements; receiving, by the processing hardware from the RAN, an indication that the pause status has not changed; and in response to determining that the UE has completed a handover from a source cell to a target cell, re-transmitting the command to change the pause status.

[0160] The following description may be applied to the description above.

[0161] Generally speaking, description for one of the above figures can apply to another of the above figures. Examples, implementations and methods described above can be combined, if there is no conflict. An event or block described above can be optional or omitted. For example, an event or block with dashed lines in the figures can be optional. In some implementations, “message” is used and can be replaced by “information element (IE)”, and vice versa. In some implementations, “IE” is used and can be replaced by “field”, and vice versa. In some implementations, “configuration” can be replaced by “configurations” or “configuration parameters”, and vice versa. In some implementations, the “LTM command” can be replaced by “serving cell change command”, “Layer 1 / Layer 2 switching command”, “lower layer switching command” or “lower layer serving cell change command”. In some implementations, “some” means “one or more”. In some implementations, “at least one” means “one or more”. In some implementations, the “DU configuration” can be replaced by “cell group configuration”. In some implementations, the “cell index” can be replaced with “candidate cell index”, “serving cell index”, “LTM cell index”, “special cell (SpCell) index”, “PCell index” or “PSCell index”. In some implementations, the “cell ID” can be replaced with a name such as “candidate cell ID”, “serving cell ID”, “SpCell ID”, “LTM cell ID”, “PCell ID” or “PSCell ID”. In some implementations, the “cell ID” in a CU-to-DU message and the “cell ID” can be replaced with different names listed above.

[0162] A user device in which the techniques of this disclosure can be implemented (e.g., the UE 102) can be any suitable device capable of wireless communications such as a smartphone, a tablet computer, a laptop computer, a mobile gaming console, a point-of-sale (POS) terminal, a health monitoring device, a drone, a camera, a media-streaming dongle or another personal media device, a wearable device such as a smartwatch, a wireless hotspot, a femtocell, or a broadband router. Further, the user device in some cases may be embedded in an electronic system such as the head unit of a vehicle or an advanced driver assistance system (ADAS). Still further, the user device can operate as an intemet-of-things (loT) device or a mobile-internet device (MID). Depending on the type, the user device can include one or more general-purpose processors, a computer-readable memory, a user interface, one or more network interfaces, one or more sensors, etc.

[0163] Certain embodiments are described in this disclosure as including logic or a number of components or modules. Modules may can be software modules (e.g., code, or machine-readable instructions stored on non-transitory machine-readable medium) or hardware modules. A hardware module is a tangible unit capable of performing certain operations and may be configured or arranged in a certain manner. A hardware module can comprise dedicated circuitry or logic that is permanently configured (e.g., as a special -purpose processor, such as a field programmable gate array (FPGA) or an application-specific integrated circuit (ASIC), a digital signal processor (DSP), etc.) to perform certain operations. A hardware module may also comprise programmable logic or circuitry (e.g., as encompassed within a general-purpose processor or other programmable processor) that is temporarily configured by software to perform certain operations. The decision to implement a hardware module in dedicated and permanently configured circuitry, or in temporarily configured circuitry (e.g., configured by software) may be driven by cost and time considerations.

[0164] When implemented in software, the techniques can be provided as part of the operating system, a library used by multiple applications, a particular software application, etc. The software can be executed by one or more general-purpose processors or one or more specialpurpose processors.

[0165] The term “or” as used herein is to be interpreted as an inclusive or meaning any one or any combination, unless expressly indicated otherwise, mutually exclusive, or indicated otherwise by context. Therefore, herein, the expression “A or B” means “A, B, or both A and B.”

[0166] Upon reading this disclosure, those of skill in the art will appreciate still additional and alternative structural and functional designs for handling mobility between base stations through the principles disclosed herein. Thus, while particular embodiments and applications have been illustrated and described, it is to be understood that the disclosed embodiments are not limited to the precise construction and components disclosed herein. Various modifications, changes and variations, which will be apparent to those of ordinary skill in the art, may be made in the arrangement, operation and details of the method and apparatus disclosed herein without departing from the scope defined in the claims.

Claims

What is claimed is:

1. A method implemented in a user equipment (UE), the method comprising: communicating in dual connectivity (DC) with a master node (MN) via an MN link, and a secondary node (SN) via an SN link; reporting quality of experience (QoE) measurements toward the SN via the SN link; and in response to detecting a radio link failure (RLF) on the SN link, suspending the reporting of the QoE measurements via the SN link.

2. The method of claim 1, further comprising, in response to the detecting of the RLF on the SN link: continuing to collect the QoE measurements.

3. The method of claim 1 or 2, further comprising, in response to the detecting of the RLF on the SN link: switching the reporting of the QoE measurements from the SN link to the MN link.

4. The method of claim 3, wherein the switching includes: switching from a signaling radio bearer 5 (SRB5), dedicated to reports of the QoE measurements, to SRB4.

5. The method of claim 3, wherein the switching includes: switching from an SN split SRB4 to an MN split SRB4.

6. The method of claim 1 or 2, further comprising: determining that the UE is not configured to report the QoE measurements toward the MN via the MN link.

7. The method of any of the preceding claims, further comprising, in response to the detecting of the RLF : transmitting, to the MN, an SCG failure information message.

8. The method of claim 7, wherein the SCG failure information message includes one or more of:(i) a current QoE configuration,(ii) a QoE report, or(iii) a QoE report available indication.

9. The method of any of the preceding claims, further comprising: performing a secondary cell group (SCG) recovery on the SN link, subsequent to the detecting of the RLF failure,.

10. The method of claim 9, further comprising: in response to detecting the SCG recovery of the SN link, resuming the reporting of the QoE measurements via the SN link.

11. The method of any of claims 1-8, further comprising: in response to detecting a release of the SN link subsequent to the detecting of the RLF failure, reconfiguring a QoE procedure with which the reporting toward the SN via the SN link was associated, to configure subsequent reporting of the QoE measurements toward the MN via the MN link.

12. The method of claim 11, wherein detecting the release of the SN link includes: receiving, from the MN, an SCG release indication.

13. A method implemented in a first radio access network (RAN) node, the method comprising: providing a master node (MN) link to a user equipment (UE) communicating in dual connectivity with the first RAN node operating as an MN, and with a second RAN node that operates as a secondary node (SN) and provides an SN link, the UE reporting quality of experience (QoE) measurements toward the SN via the SN link; receiving, from the UE, an indication of a failure of the SN link; andtransmitting, to the UE, an indication of whether the UE is to switch the reporting of the QoE measurements to the MN link.

14. The method of claim 13, wherein the indication instructs the UE to release an SRB5 or a split SRB4.

15. An apparatus comprising a transceiver and processing hardware, the UE configured to implement a method of any of the preceding claims.

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