Method and apparatus for master cell group

Abstract

To achieve coexistence of a DAPS handover procedure and an RLF report mechanism.SOLUTION: Embodiments of the present application relate to a method and an apparatus for a master cell group, for example, a dual active protocol stack (DAPS) and a radio link failure (RLF) report mechanism associated with a source link during a DAPS handover procedure under a 3rd Generation Partnership Project (3GPP) 5G New Radio (NR) system or the like. According to an embodiment of the present application, the method can include the steps of: receiving configuration information including a timer associated with fast MCG link recovery; receiving a radio resource control (RRC) reconfiguration message including DAPS configuration information; in response to an RLF of a source link relating an MCG, initiating an MCG failure information procedure based on a condition whether the timer for handover is running or not. In addition, an RLF-report may be reported to a target cell after a UE successfully accesses to the target cell.SELECTED DRAWING: Figure 5A

Description

[Technical Field]

[0001] Embodiments of the present application generally relate to wireless communication technologies, and more particularly, to methods and apparatus for, for example, a master cell group (MCG) for a dual active protocol stack (DAPS) handover procedure and a source link related radio link failure (RLF) reporting mechanism for the MCG during a DAPS handover procedure. [Background technology]

[0002] When a radio link failure (RLF) or handover failure (HOF) occurs in a user equipment (UE), the UE may perform a radio resource control (RRC) re-establishment procedure. The UE may access a cell through a successful RRC re-establishment procedure, or through a connection setup procedure in response to a failed RRC re-establishment procedure. The accessed network requests UE information, including the UE's RLF report, so that the network can optimize mobility issues based on the UE information from the UE. Therefore, the UE sends a failure report to the network.

[0003] In the 3rd Generation Partnership Project (3GPP), after a UE receives a handover command related to a DAPS handover procedure, the connection with the source base station (BS) continues to be maintained until the UE releases the source cell of the source BS after successfully completing a random access procedure to the target BS.

[0004] Currently, details on how to solve the coexistence problem of the DAPS handover procedure and the RLF reporting mechanism in 3GPP 5G New Radio (NR) systems and the like have not yet been specifically discussed. Summary of the Invention [Means for solving the problem]

[0005] Some embodiments of the present application provide a method for wireless communication. The method may be executed by a UE. The method includes receiving configuration information including a timer associated with fast master cell group (MCG) link recovery, receiving a radio resource control (RRC) reconfiguration message including dual-active protocol stack (DAPS) configuration information, performing a DAPS handover procedure, starting a timer for the handover, initiating an MCG failure information procedure when the timer for the handover is running in response to a radio link failure (RLF) of a source link for the MCG during the DAPS handover procedure, and starting a timer associated with fast MCG link recovery.

[0006] Some embodiments of the present application also provide an apparatus for wireless communication, the apparatus including: a non-transitory computer-readable medium having computer-executable instructions stored thereon; a receiving circuit; a transmitting circuit; and a processor coupled to the non-transitory computer-readable medium, the receiving circuit, and the transmitting circuit, the computer-executable instructions causing the processor to implement the above-mentioned method performed by a UE.

[0007] Some embodiments of the present application provide a further method for wireless communications. The method may be executed by a UE. The method includes receiving configuration information including a timer associated with fast master cell group (MCG) link recovery, and initiating an MCG failure information procedure in response to a radio link failure (RLF) of a source link for the MCG during a dual-active protocol stack (DAPS) handover procedure when the timer associated with fast MCG link recovery is not running and the timer for handover is not running.

[0008] Some embodiments of the present application also provide an apparatus for wireless communication, the apparatus including: a non-transitory computer-readable medium having computer-executable instructions stored thereon; a receiving circuit; a transmitting circuit; and a processor coupled to the non-transitory computer-readable medium, the receiving circuit, and the transmitting circuit, the computer-executable instructions causing the processor to implement the above-described further method performed by the UE.

[0009] Some embodiments of the present application provide a further method for wireless communication. The method may be executed by a UE. The method includes receiving a radio resource control (RRC) reconfiguration message including a reconfiguration information element (IE) with synchronization and dual-active protocol stack (DAPS) configuration information, performing a DAPS handover procedure, and, in response to a radio link failure (RLF) of a source link with respect to a master cell group (MCG) during the DAPS handover procedure, transmitting an RLF report related to the RLF after successfully completing the DAPS handover procedure.

[0010] Some embodiments of the present application also provide an apparatus for wireless communication, the apparatus including: a non-transitory computer-readable medium having computer-executable instructions stored thereon; a receiving circuit; a transmitting circuit; and a processor coupled to the non-transitory computer-readable medium, the receiving circuit, and the transmitting circuit, the computer-executable instructions causing the processor to implement the above-described further method performed by the UE.

[0011] Some embodiments of the present application provide a further method for wireless communication. The method may be executed by a BS. The method includes the steps of: sending a user equipment (UE) information request; receiving a UE information response including a radio link failure (RLF) report, where the RLF report includes information related to a radio link failure (RLF) of a source link with respect to a master cell group (MCG) during a dual-active protocol stack (DAPS) handover procedure; and sending a failure indication, where the failure indication includes an information element (IE) regarding successful completion of the DAPS handover procedure.

[0012] Some embodiments of the present application also provide an apparatus for wireless communication, the apparatus including: a non-transitory computer-readable medium having computer-executable instructions stored thereon; a receiving circuit; a transmitting circuit; and a processor coupled to the non-transitory computer-readable medium, the receiving circuit, and the transmitting circuit, wherein the computer-executable instructions cause the processor to implement the above-mentioned further method performed by the BS.

[0013] The details of one or more examples are set forth in the accompanying drawings and the description below. Other features, objects, and advantages will become apparent from the description and drawings, and from the claims.

[0014] To explain how the advantages and features of the present application may be obtained, the description of the present application will be given by reference to specific embodiments that are illustrated in the accompanying drawings. These drawings depict only exemplary embodiments of the present application and therefore should not be considered as limiting its scope. [Brief explanation of the drawings]

[0015] [Figure 1] 1 is a schematic diagram of a wireless communication system according to some embodiments of the present application. [Figure 2] 1 is an exemplary flowchart of a fault information procedure according to some embodiments of the present application. [Figure 3] 1 is an exemplary flowchart of an intra-AMF (Access and Mobility Management Function) handover procedure according to some embodiments of the present application. [Figure 4] FIG. 1 illustrates an example timeline for RLF with fast MCG link recovery procedure according to some embodiments of the present application. [Figure 5A] 1 is a flowchart of a method for a DAPS handover procedure according to some embodiments of the present application. [Figure 5B] 1 is a flowchart of a method for an MCG fault information procedure according to some embodiments of the present application. [Figure 6] 1 is a schematic diagram of a wireless communication system according to some embodiments of the present application. [Figure 7] FIG. 1 illustrates an exemplary signal transmission procedure according to some embodiments of the present application. [Figure 8] 1 is a flowchart of a method for a fault information procedure according to some embodiments of the present application. [Figure 9] FIG. 10 illustrates a further exemplary signal transmission procedure according to some embodiments of the present application. [Figure 10] 10 is a further flowchart of a method for a fault indication procedure according to some embodiments of the present application. [Figure 11]11 is a simplified block diagram of an apparatus 1100 for an enhanced fault reporting mechanism according to some embodiments of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0016] The detailed description of the accompanying drawings is intended as an illustration of a preferred embodiment of the present application and is not intended to represent the only form in which the present application may be practiced. It should be understood that the same and equivalent functions may be accomplished by different embodiments that are intended to be encompassed within the spirit and scope of the present application.

[0017] Reference will now be made in detail to several embodiments of the present application, examples of which are illustrated in the accompanying drawings. For ease of understanding, the embodiments are provided under specific network architectures and new service scenarios, such as 3GPP 5G, 3GPP LTE Release 8, etc. With the development of network architectures and new service scenarios, it is contemplated that all embodiments in the present application are also applicable to similar technical problems, and further, the terms described in the present application may be changed, which shall not affect the principles of the present application.

[0018] Next generation radio access networks (NG-RAN) support multi-radio dual connectivity (MR-DC) operation. In MR-DC operation, a UE with multiple transceivers may be configured to utilize resources provided by two different nodes connected through a non-ideal backhaul, where one node may provide NR access and the other node may provide either Evolved Universal Mobile Telecommunication System (UMTS) Terrestrial Radio Access (UTRA) (E-UTRA) or NR access. One node may function as a master node (MN) and the other node may function as a secondary node (SN). The MN and SN are connected via a network interface (e.g., the Xn interface specified in 3GPP standard documents), and at least the MN is connected to a core network.

[0019] FIG. 1 shows a schematic diagram of a wireless communication system according to some embodiments of the present application.

[0020] As shown in Figure 1, the wireless communication system 100 may be a dual connectivity system 100 that includes at least one UE 101, at least one MN 102, and at least one SN 103. In particular, the dual connectivity system 100 in Figure 1 includes, for illustrative purposes, one illustrated UE 101, one illustrated MN 102, and one illustrated SN 103. Although a particular number of UEs 101, MNs 102, and SNs 103 are shown in Figure 1, it is contemplated that any number of UEs 101, MNs 102, and SNs 103 may be included within the wireless communication system 100.

[0021] 1, a UE 101 may be connected to a MN 102 and an SN 103 via a network interface, for example, a Uu interface defined in a 3GPP standard document. The MN 102 and the SN 103 may be connected to each other via a network interface, for example, an Xn interface defined in a 3GPP standard document. The MN 102 may be connected to a core network via a network interface (not shown in FIG. 1). The UE 102 may be configured to utilize resources provided by the MN 102 and the SN 103 to perform data transmission.

[0022] The MN 102 may refer to a radio access node that provides a control plane connection to a core network. In one embodiment of the present application, in an E-UTRA-NR DC (EN-DC) scenario, the MN may be an eNB. In another embodiment of the present application, in a Next Generation E-UTRA-NR DC (NGEN-DC) scenario, the MN may be an ng-eNB. In yet another embodiment of the present application, in an NR-DC scenario or an NR-E-UTRA DC (NE-DC) scenario, the MN may be a gNB.

[0023] The MN 102 may be associated with an MCG. The MCG may refer to a group of serving cells associated with the MN 102 and may include a primary cell (PCell) of the MCG and optionally one or more secondary cells (SCells) of the MCG. The PCell may provide a control plane connection to the UE 101.

[0024] The SN 103 may refer to a radio access node that does not have a control plane connection to a core network but provides additional resources to the UE 101. In one embodiment of the present application, in an EN-DC scenario, the SN 103 may be an en-gNB. In another embodiment of the present application, in an NE-DC scenario, the SN 103 may be an ng-eNB. In yet another embodiment of the present application, in an NR-DC scenario or an NGEN-DC scenario, the SN 103 may be a gNB.

[0025] The SN 103 may be associated with a secondary cell group (SCG). The SCG may refer to a group of serving cells associated with the SN 103 and may include a primary secondary cell (PSCell) and optionally one or more secondary cells (SCells).

[0026] The PCell of the MCG and the PSCell of the SCG may also be called a special cell (SpCell).

[0027] In some embodiments of the present application, the UE 101 may include a computing device such as a desktop computer, a laptop computer, a personal digital assistant (PDA), a tablet computer, a smart television (e.g., a television connected to the Internet), a set-top box, a game console, a security system (including security cameras), an in-vehicle computer, a network device (e.g., a router, a switch, and a modem). In some other embodiments of the present application, the UE 101 may include a portable wireless communication device, a smartphone, a cellular telephone, a flip phone, a device with a subscriber identity module, a personal computer, selective call reception circuitry, or any other device capable of transmitting and receiving communication signals over a wireless network. In some other embodiments of the present application, the UE 101 may include a wearable device such as a smart watch, a fitness band, an optical head-mounted display, etc. Furthermore, the UE 101 may be referred to as a subscriber unit, a mobile, a mobile station, a user, a terminal, a mobile terminal, a wireless terminal, a fixed terminal, a subscriber station, a user terminal, or a device, or may be described using other terms used in the art.

[0028] 2 shows an exemplary flowchart of a fault information procedure according to some embodiments of the present application. The fault information procedure may be referred to as a fault information reporting procedure. The embodiment of FIG. 2 includes the following embodiments of the SCG fault information procedure or the MCG fault information procedure:

[0029] Specifically, in some embodiments of the SCG failure information procedure, in operation 201 shown in FIG. 2, the UE 101 and the MN 102 may communicate RRC reconfiguration information. In operation 202 shown in FIG. 2, the UE 101 may initiate an SCG failure information procedure and send a message related to an SCG failure to the MN 102. The message related to the SCG failure in operation 202 may be an SCGFailureInformation message defined in a 3GPP standard document. The MN 102 may then process the SCGFailureInformation message and determine whether to maintain the SN or SCG, change the SN or SCG, or release the SN or SCG. The SN may be the SN 103 shown and illustrated in FIG. 1.

[0030] In the above-described embodiment of the SCG Failure Information procedure, the UE 101 may initiate the SCG Failure Information procedure to report a failure of the SCG if one of the following conditions is met: When an SCG failure is detected. For example, an SCG failure may refer to an RLF occurring in a PSCell of the SCG. · During reconfiguration with SCG synchronization failure. -When SCG configuration fails. When a lower layer of the SCG indicates a failure in the integrity check for a signaling radio bearer (SRB)3.

[0031] In 3GPP Release 16, a fast MCG link recovery procedure was introduced for MR-DC scenarios. The fast MCG link recovery procedure is sometimes also called the MCG failure information procedure. The purpose of this procedure is to inform the MN, via the SN connected to the UE, of the RLF of the MCG so that a UE in RRC_CONNECTED state can initiate a fast MCG link recovery procedure to quickly continue the RRC connection without performing a re-establishment procedure.

[0032] In some other embodiments of FIG. 2 of the present application, when an MCG failure occurs, the UE 101 may initiate (or trigger) a fast MCG link recovery procedure, i.e., an MCG failure information procedure.

[0033] Specifically, in some embodiments of the MCG failure information procedure, as shown in FIG. 2, in operation 201, the UE 101 and the MN 102 may communicate RRC reconfiguration information. In operation 202, the UE 101 may initiate an MCG failure information procedure and transmit a message related to the MCG failure to the MN 102. For example, the MCG failure may refer to an RLF occurring in the PCell of the MCG. The message related to the MCG failure in operation 202 may be an MCGFailureInformation message specified in a 3GPP standard document.

[0034] In an embodiment of the MCG failure information procedure, the UE 101 may not directly send a message related to the MCG failure to the MN 102. Instead, the UE 101 may send a message related to the MCG failure to an SN (e.g., the SN 103 shown and illustrated in FIG. 1), which may then forward the message received from the UE 101 to the MN 102.

[0035] For example, UE 101 may be configured to report MCG failure information via split SRB1 or SRB3 when an MCG failure occurs. If split SRB1 is configured, UE 101 may submit an MCGFailureInformation message to lower layers, e.g., for transmission via SRB1. If SRB3 is configured, UE 101 may submit an MCGFailureInformation message to lower layers, e.g., for transmission via SRB3. For example, the MCGFailureInformation message may be embedded within the NR RRC message ULInformationTransferMRDC specified in the 3GPP standard document for transmission via SRB3.

[0036] When or after sending the message in operation 202, the UE 101 may start a timer associated with the fast MCG link recovery procedure. In an embodiment of the present application, the timer associated with the fast MCG link recovery procedure may be T316, which is specified in the 3GPP standard document.

[0037] After receiving the message related to the MCG failure, the MN 102 may further send a response message to the UE 101. The response message may be an RRC reconfiguration message including a handover (HO) command for the cell. The response message may be an RRC release message. In one embodiment of the present application, the handover command may be a reconfigurationWithSync configuration specified in the 3GPP standard document. The MN 102 may not send the response message directly to the UE 101. Instead, the MN 102 may send the response message to an SN (SN 103 shown and illustrated in FIG. 1), and the SN may then forward the response message to the UE 101.

[0038] If the SRB3 is configured to send a message related to the failure of the MCG, after receiving the response message from the MN102, the SN103 may encapsulate the response message in a DLInformationTransferMRDC message specified in the 3GPP standard document, and then send the DLInformationTransferMRDC message to the UE101.

[0039] In the above-described embodiment of the MCG failure information procedure, the UE 101 may set the MCG failure type (referred to as "failureType") as follows: When the timer T310 (sometimes called the physical layer problem timer) specified in the 3GPP standard document expires, the UE 101 sets the failureType to t310-Expiry, which is specified in the 3GPP standard document. When the UE 101 initiates the transmission of the MCGFailureInformation message as shown in operation 202 to provide a random access problem indication from the medium access control (MAC) layer of the MCG, the UE 101 sets the failureType as randomAccessProblem as specified in the 3GPP standard documents. When the UE 101 initiates the transmission of the MCGFailureInformation message as shown in operation 202 to provide an indication from the MCG radio link control (RLC) that the maximum number of retransmissions has been reached, the UE 101 sets the failureType as rlc-MaxNumRetx as specified in the 3GPP standard documents.

[0040] When performing a DAPS handover procedure, the UE continues to receive downlink user data from the source BS until it releases the source cell of the source BS, and the UE continues to send uplink user data transmissions to the source BS until it successfully completes the random access procedure to the target BS. If the DAPS handover procedure fails, the UE may report a DAPS handover (HO) failure via the source BS without triggering an RRC connection re-establishment procedure if the source link is not released.

[0041] In the control plane process of the handover related to the DAPS handover procedure, messages are exchanged directly between the BSs. A specific example is shown in Figure 3 below.

[0042] 3 illustrates an exemplary flowchart of an intra-AMF handover procedure according to some embodiments of the present application. The embodiment of FIG. 3 illustrates a basic conditional handover scenario in which neither the access and mobility management function (AMF) nor the user plane function (UPS) changes.

[0043] 3, in operation 301, a source BS may send measurement configuration information to a UE. The UE may report measurement results to the source BS based on the measurement configuration information. In operation 302, the source BS may decide to hand over the UE, which may be based on the measurement results reported by the UE.

[0044] In operation 303, the source BS may send a handover request message to the target BS. For example, the handover request message may pass a transparent RRC container having information necessary to prepare the handover procedure at the target BS side.

[0045] In operation 304, after receiving the handover request message from the source BS, the target BS may perform admission control based on the load of the target cell of the target BS to determine whether to allow the handover procedure for the UE.

[0046] In operation 305, based on the admission control result, the target BS may prepare handover resources for the UE and send a HANDOVER REQUEST ACKNOWLEDGE including an RRC reconfiguration message to the source BS.

[0047] In operation 306, RAN handover initiation is performed. The source BS may send an RRC reconfiguration message to the UE. The RRC reconfiguration message may include a reconfiguration information element (IE) with synchronization. The RRC reconfiguration message may include information necessary to access a target cell of the target BS.

[0048] In operation 307, the source BS may send an SN STATUS TRANSFER message to the target BS.

[0049] In operation 308, the UE may complete the handover procedure by accessing the target cell and sending an RRCReconfigurationComplete message to the target BS. In some embodiments implementing a DAPS handover procedure, the UE does not move away from the source cell upon receiving the RRCReconfiguration message. For example, the UE may release source resources upon receiving an explicit release indication from the target BS.

[0050] In operation 309, the target BS may send a PATH SWITCH REQUEST message to the AMF to trigger the 5G core (5GC) network to switch the downlink (DL) data path toward the target BS.

[0051] In operation 310, the 5GC network may switch the DC data path toward the target BS. The UPF may send one or more "end marker" packets on the old (source) data path to the source BS for each packet data unit (PDU) session or PDU tunnel. The UPF may then release any user plane or transport network layer (TNL) toward the source BS.

[0052] In operation 311, the AMF may acknowledge the PATH SWITCH REQUEST message with a PATH SWITCH REQUEST ACKNOWLEDGE message.

[0053] In operation 312, in response to receiving the PATH SWITCH REQUEST ACKNOWLEDGE message from the AMF, the target BS may send a UE CONTEXT RELEASE message to notify the source BS about the success of the handover procedure. The source BS may then release radio and control plane-related resources associated with the UE context. Ongoing data transfers may continue.

[0054] 4 illustrates an example timeline for an RLF with Fast MCG Link Recovery procedure according to some embodiments of the present application. The embodiment of FIG. 4 may be performed by a UE (e.g., the UE 101 shown and illustrated in FIG. 1).

[0055] As shown in Figure 4, the UE first performs data transmission in a normal operation phase. The UE detects a radio link problem, for example, when the MAC layer of the UE receives an N310 consecutive out-of-sync indication from the physical layer of the UE, which means that a radio link problem has occurred. Then, the UE starts a timer, for example, timer T310 specified in the 3GPP standard document. During the timer T310 period, if the MAC layer of the UE receives an N311 consecutive out-of-sync indication from the physical layer, which means that the UE has successfully connected to the network, the UE may stop timer T310.

[0056] If timer T310 expires, this means that there is no recovery during timer T310, and the UE initiates a fast MCG link recovery procedure. Specifically, the UE transmits MCG failure information to an MN (e.g., the MN 102 shown in FIG. 1) via an SN (e.g., the SN 103 shown in FIG. 1) and starts timer T316, which is specified in the 3GPP standard document, as shown in FIG. 4. If the UE receives an RRC reconfiguration from the MN via the SN, the UE stops timer T316, which means that the fast MCG link recovery procedure has ended. Otherwise, in response to the expiration of timer T316, which means that there is no recovery during timer T316, the UE performs an RRC re-establishment procedure and starts timer T311, which is specified in 3GPP for cell selection.

[0057] If timer T311 expires, meaning there is no recovery during timer T311, the UE returns to an idle state, e.g., RRC_IDLE state. Before timer T311 expires, the UE is in RRC_CONNECTED state as shown in Figure 4. Before timer T311 expires, the UE enters RRC_IDLE state as shown in Figure 4.

[0058] The above description of the embodiment of Figure 4 does not take into account timer T312. Some embodiments assume that timer T312, as specified in 3GPP standard documents, is configured. In these embodiments, if timer T310 is running and a measurement report for a measurement identity for which timer T312 is configured is triggered, the UE starts timer T312. The UE may declare a failure and trigger a failure recovery procedure, for example, a configured fast MCG link recovery procedure.

[0059] The embodiments of the present application provide a coexistence scenario between the DAPS handover procedure and the RLF reporting mechanism for the MCG. Further details of the embodiments of the present application are described in the following text in combination with the accompanying drawings.

[0060] Embodiments of the present application may solve the following problems: (1) how to handle the case where an RLF occurs in the source link of an MCG when a Fast MCG Link Recovery procedure is configured for the UE while the UE is performing a DAPS handover procedure, and (2) how to handle the case where the UE receives a response from the MN via the SN while a timer associated with Fast MCG Link Recovery is running and a DAPS handover procedure is in progress. Specific examples are described and shown in Figures 5A and 5B.

[0061] FIG. 5A shows a flowchart of a method for a DAPS handover procedure according to some embodiments of the present application.

[0062] The method 500A shown in FIG. 5A may be performed by a UE (e.g., the UE 101 shown and illustrated in FIGS. 1 and 2). For example, the UE may be configured by a DC to which the UE is connected to a MN (e.g., the MN 102 shown and illustrated in FIGS. 1 and 2) and a SN 103 (e.g., the SN 103 shown and illustrated in FIG. 1).

[0063] In the embodiment of FIG. 5A, when the UE is performing a DAPS handover procedure, the UE may be permitted to initiate or trigger a fast MCG link recovery procedure (eg, an MCG failure information procedure).

[0064] In one example, if a fast MCG link recovery procedure is triggered (e.g., timer T316 is running) when the UE is performing a DAPS handover procedure, the UE may report MCG failure information to the source MN via the SN. The source MN may send an RRC reconfiguration message containing a handover command to the UE or send a release message to the UE. In this case, if a DAPS handover procedure is in progress, an RRC connection re-establishment procedure should not be triggered by the UE upon expiration of a timer associated with fast MCG link recovery (e.g., timer T316).

[0065] In a further example, if a timer for handover is triggered (e.g., timer T304 is running), the UE does not initiate an RRC connection re-establishment procedure after a timer associated with fast MCG link recovery (e.g., timer T316) expires.

[0066] In another example, if a timer for handover has not been triggered (e.g., timer T304 is not running), the UE may initiate the RRC connection re-establishment procedure after a timer associated with fast MCG link recovery (e.g., timer T316) expires.

[0067] 5A, in operation 501, the UE may receive configuration information including a timer associated with fast MCG link recovery. For example, the timer associated with fast MCG link recovery may be timer T316 specified in the 3GPP standard document.

[0068] In operation 503, the UE may receive an RRC reconfiguration message. The RRC reconfiguration message may include DAPS configuration information. The DAPS configuration information may be a DAPS bearer. In operation 505, the UE may perform a DAPS handover procedure.

[0069] In operation 507, the UE may start a timer for handover. A timer value of the timer for handover may be included in the reconfiguration with the synchronization IE. In an embodiment of the present application, the timer for handover is timer T314 specified in the 3GPP standard document.

[0070] In operation 509, in response to an RLF of the source link for the MCG during the DAPS handover procedure, the UE initiates an MCG failure information procedure when the timer for the handover is running. In operation 511, the UE may start a timer (e.g., timer T316) associated with fast MCG link recovery included in the configuration information received in operation 501.

[0071] In one embodiment of the present application, the UE may transmit an MCG failure information message in response to initiating an MCG failure information procedure. If a timer associated with fast MCG link recovery expires when or after transmitting the MCG failure information message, the UE may not initiate an RRC connection re-establishment procedure when performing a DAPS handover procedure.

[0072] When transmitting or after transmitting the MCG failure information message, the UE may receive another RRC reconfiguration message. For example, the UE may receive this RRC reconfiguration message after transmitting the MCG failure information message. The UE may receive this RRC reconfiguration message when a timer associated with fast MCG link recovery is running. For example, this RRC reconfiguration message may include a reconfiguration with synchronization IE. The reconfiguration with synchronization IE may be the reconfigurationWithSync IE specified in the 3GPP standard document.

[0073] In one example, after receiving the above-mentioned another RRC reconfiguration message, the UE may perform a reconfiguration procedure with synchronization, and the UE may stop performing the ongoing DAPS handover procedure. In another example, after receiving the above-mentioned another RRC reconfiguration message, the UE may ignore this RRC reconfiguration message but continue performing the ongoing DAPS handover procedure.

[0074] In one embodiment of the present application, the UE may receive an RRC release message. For example, the UE may receive the RRC release message after transmitting an MCG failure information message. The UE may receive the RRC release message when a timer associated with fast MCG link recovery is running. After receiving the RRC release message, the UE may release resources associated with the source link where the RLF occurred and continue to perform the DAPS handover procedure. Alternatively, the UE may ignore the RRC release message and continue to perform the DAPS handover procedure.

[0075] The following text describes a specific embodiment 1 of the method shown and illustrated in FIG. 5A for solving the above problem.

[0076] According to embodiment 1, the UR (for example, the UE 101 shown and illustrated in FIGS. 1 and 2) performs the following operations: (1) The UE accesses the network via DC operation. · The configuration of the MCG and SCG can be configured in the UE. Fast MCG link recovery procedure, e.g. the value of timer T316, can be configured in the UE. (2) The UE reports the measurement results to the network (e.g., PCell or PSCell). (3) The source BS sends a handover request message to the target BS. (4) The target BS prepares handover resources for the UE and sends a HANDOVER REQUEST ACKNOWLEDGE containing an RRC reconfiguration message to the source BS. (5) The source BS sends an RRC reconfiguration message to the UE, including a ReconfigurationWithSync IE, which contains information required to access the target cell of the target BS. This operation of the BS is related to the operation 306 in Figure 3. The RRC reconfiguration message including the reconfigurationWithSync IE may be used for mobility purposes. For example, the RRC reconfiguration message including the reconfigurationWithSync IE may be used for a normal handover procedure, a conditional handover procedure, a DAPS handover procedure, and / or a PSCell change procedure. Configuration information for the DAPS handover procedure (eg, dapsConfig as defined in the 3GPP standard document) can be configured for the data radio bearer (DRB). (6) The UE accesses the target cell. In the case of a DAPS handover procedure, the UE does not leave the source cell even when it receives an RRC reconfiguration message. The UE continues to monitor the source cell. (7) When the UE performs a DAPS handover procedure, the UE detects an RLF in the source PCell. (8) The UE sends an MCG failure information message to the MN via the SN and starts timer T316. (9) UE adopts different actions under different scenarios. (a) If the UE receives a response from the MN via the SN before timer T316 expires, If the UE receives an RRC reconfiguration message containing a reconfigurationWithSync IE: Option A-1: ​​The UE may perform a reconfiguration procedure with synchronization and stop the ongoing DAPS handover procedure. Option A-2: The UE ignores the received RRC reconfiguration message and continues with the ongoing DAPS handover procedure. When the UE receives an RRC release message: Option B-1: The UE may release the source connection and continue with the ongoing DAPS handover procedure. Option B-2: The UE may ignore the received RRC reconfiguration message and continue with the ongoing DAPS handover procedure. (b) If the UE does not receive a response from the MN via the SN before the timer T316 expires, i.e., if the timer T316 expires, Option (1): If timer T304 is running, no re-establishment procedure should be triggered in response to timer T316 expiring. Option (2): The UE may initiate a re-establishment procedure in response to the expiration of timer T316 only if timer T304 is not running. (10) The UE continues the DAPS handover procedure and accesses the target cell.

[0077] 5B shows a flowchart of a method for an MCG failure information procedure according to some embodiments of the present application. The method 500B shown in FIG. 5B may be performed by a UE (e.g., the UE 101 shown and illustrated in FIGS. 1 and 2). The UE may be configured by a DC to which the UE is connected to a MN (e.g., the MN 102 shown and illustrated in FIGS. 1 and 2) and a SN 103 (e.g., the SN 103 shown and illustrated in FIG. 1).

[0078] In the embodiment of Figure 5B, when the UE is performing a DAPS handover procedure, the UE may not be allowed to initiate or trigger a fast MCG link recovery procedure (e.g., an MCG failure information procedure). Under certain conditions, the UE may initiate or trigger a fast MCG link recovery procedure (e.g., an MCG failure information procedure).

[0079] 5B, in operation 502, the UE may receive configuration information including a timer associated with fast MCG link recovery, for example, timer T316 specified in a 3GPP standard document. In operation 504, if an RLF occurs on a source link for an MCG during a DAPS handover procedure, the UE may initiate an MCG failure information procedure when a timer associated with fast MCG link recovery (e.g., timer T316) is not running and the timer for handover is not running.

[0080] In one embodiment of the present application, the timer for handover is timer T304 specified in the 3GPP standard document. In this embodiment, if an RLF occurs on the source link of the MCG, if timer T316 is not running, and if timer T304 is not running, the UE may initiate an MCG failure information procedure.

[0081] In another embodiment of the present application, the timer for handover is associated with DAPS configuration information. For example, the DAPS configuration information is included in the RRC reconfiguration message received by the UE. In this embodiment, if an RLF occurs on the source link of the MCG, if timer T316 is not running, and if DAPS configuration is not configured for any DRB, the UE may initiate an MCG failure information procedure.

[0082] The following text describes a specific embodiment 2 of the method shown and illustrated in FIG. 5B for solving the above problem.

[0083] According to embodiment 2, a UE (for example, the UE 101 shown and illustrated in Figures 1 and 2) and a MN (for example, the MN 102 shown and illustrated in Figures 1 and 2) perform the following operations. (1) The UE accesses the network via DC operation. · The configuration of the MCG and SCG can be configured in the UE. Fast MCG link recovery procedure, e.g. the value of timer T316, can be configured in the UE. (2) The UE detects RLF in the source link for the MCG (e.g., PCell). (3) UE adopts different actions under different scenarios. · When detecting RLF of the MCG, if timer T316 is not running and timer T304 is not running, the UE may initiate an MCG failure information procedure. ·When detecting RLF of MCG, if timer T316 is not running and DAPS configuration is not configured for any DRB, the UE may initiate an MCG Failure Information procedure. After initiating the MCG Failure Information procedure, the UE may suspend SCG transmissions for all signaling radio bearers (SRBs) and DRBs except for signaling radio bearer (SRB) 0. (4) The UE sends an MCG failure information message to the MN via the SN and starts timer T316. The type of failure and available measurement results are included in the MCG failure information message. (5) After receiving the MCG failure information message via the SN, the MN may send a response (eg, RRC reconfiguration with a reconfigurationWithSync IE) to the UE. (6) The UE receives a response (e.g., an RRC reconfiguration with a reconfigurationWithSync IE) from the MN via the SN. The UE may then perform handover and synchronization procedures to the target cell.

[0084] The details described in all other embodiments of this application (e.g., details of how to solve the coexistence problem of the DAPS handover procedure and the RLF reporting mechanism for the MCG) are applicable to the embodiments of Figures 5A and 5B. Furthermore, the details described in the embodiments of Figures 5A and 5B are applicable to all embodiments of Figures 1 to 4 and 6 to 11.

[0085] FIG. 6 shows a schematic diagram of a wireless communication system according to some embodiments of the present application.

[0086] 6, the wireless communication system 600 includes at least one user equipment (UE) 601 and at least one base station (BS) 602. In particular, the wireless communication system 600 includes, for illustrative purposes, one UE 601 (e.g., UE 601a) and two BSs 602 (e.g., BSs 602a and 602b). Although a particular number of UEs 601 and BSs 602 are shown in FIG. 6, it is contemplated that any number of UEs 601 and BSs 602 may be included within the wireless communication system 600.

[0087] The UE 601 shown and illustrated in Figure 6 has the same functions and characteristics as the UE 101 shown and illustrated in Figure 1. For details, please refer to the above description regarding the embodiment of Figure 1.

[0088] The BSs 602 may be distributed throughout a geographic region. In certain embodiments of the present application, each of the BSs 602 may also be referred to as an access point, access terminal, base, base unit, macrocell, Node-B, evolved Node-B (eNB), gNB, NG-RAN (next generation radio access network) node, home Node-B, relay node, or device, or may be described using other terms used in the art. The BSs 602 are generally part of a radio access network, which may include one or more controllers communicatively coupled to one or more corresponding BSs 602. The BSs 602 may communicate directly with each other. For example, the BSs 602 may communicate directly with each other via an Xn interface or an X2 interface.

[0089] The wireless communication system 600 may be compatible with any type of network capable of transmitting and receiving wireless communication signals. For example, the wireless communication system 600 may be compatible with a wireless communication network, a cellular telephone network, a Time Division Multiple Access (TDMA)-based network, a Code Division Multiple Access (CDMA)-based network, an Orthogonal Frequency Division Multiple Access (OFDMA)-based network, an LTE network, a 3GPP-based network, a 3GPP 5G network, a satellite communication network, a high altitude platform network, and / or other communication networks.

[0090] In some embodiments of the present application, the wireless communication system 600 is compatible with the 3GPP protocol 5G NR, where the BS 602 transmits data using an OFDM modulation scheme on the DL and the UE 601 transmits data using a single-carrier frequency division multiple access (SC-FDMA) or OFDM scheme on the UE. However, more generally, the wireless communication system 600 may implement several open or proprietary communication protocols, such as WiMAX, among other protocols.

[0091] In some embodiments of the present application, the BS 602 may communicate using other communication protocols, such as the IEEE 802.11 family of wireless communication protocols. Additionally, in some embodiments of the present application, the BS 602 may communicate over licensed spectrum, while in other embodiments, the BS 602 may communicate over unlicensed spectrum. This application is not intended to be limited to any particular wireless communication system architecture or protocol implementation. In further implementations of the present application, the BS 602 may communicate with the UE 601 using 3GPP 5G protocols.

[0092] Each BS 602 may include one or more cells. Each UE 601 may perform cell section procedures between different cells of different BSs. Each UE 601 may handover from a serving cell of a source BS to a target cell of a target BS. For example, in the wireless communication system 600 illustrated and shown in FIG. 6, BS 602a may function as a source BS and BS 602b may function as a target BS. If there is a need for handover, UE 601a illustrated and shown in FIG. 6 may perform a handover from the serving cell of BS 602a to the target cell of BS 602b, which depends on the result of the cell selection procedure. The handover procedure performed by UE 601a may be a CHO procedure.

[0093] Currently, in 3GPP 5G NR systems and the like, radio access operating with shared spectrum channel access can operate in different modes, such as a mode in which either the PCell, PSCell, or SCell may be in the shared spectrum, or a mode in which the SCell may or may not be configured in the uplink. A BS may operate in either a dynamic access mode or a semi-static channel access mode, as described in 3GPP standard document TS37.213. In both of these channel access modes, the BS and UE may apply Listen-Before-Talk (LBT) before transmitting in a cell configured with shared spectrum channel access. When LBT is applied, the transmitter listens or senses the channel to determine whether it is free or busy, and transmits only if the channel is free.

[0094] If the UE detects a consistent uplink LBT failure, it takes the actions specified in the 3GPP standard document T38.321. The detection is per Bandwidth Part (BWP) and is based on all uplink transmissions within this BWP. When a consistent uplink LBT failure is detected in an SCell, the UE reports this to the corresponding BS (MN in an MCG or SN in an SCG) via the MAC CE on a serving cell different from the SCell where the failure was detected. If there are no available resources to transmit the MAC CE, a Scheduling Request (SR) may be sent by the UE. When a consistent uplink LBT failure is detected in an SpCell, the UE switches to another UL BWP with configured RACH resources in that cell, initiates a RACH, and reports the failure via the MAC CE. If multiple UL BWPs are available to switch to, it is up to the UE implementation to select which UL BWP to use. For a PSCell, if a consistent uplink LBT failure is detected in all UL BWPs with configured RACH resources, the UE declares an SCG RLF and reports the failure to the MN via SCGFailureInformation.For a PCell, if an uplink LBT failure is detected in all UL BWPs with configured RACH resources, the UE declares an RLF.

[0095] The embodiments of the present application may solve the following problems: (1) what additional information should be added to the RLF report when an RLF occurs at the source while the UE is performing a DAPS handover procedure, and (2) what information should be sent to the source cell after the target cell receives the RLF report from the UE. Specific examples are described and illustrated in Figures 7 to 10.

[0096] FIG. 7 illustrates an exemplary signaling procedure according to some embodiments of the present application.

[0097] Specifically, as shown in FIG. 7, in operation 701, a UE (e.g., UE 101 illustrated and shown in FIG. 1 or UE 601a illustrated and shown in FIG. 6) transmits a message related to an MCG failure to a target BS (e.g., BS 602b illustrated and shown in FIG. 6). The target BS controls a target cell of the UE. For example, the message related to the MCG failure in operation 701 may be an RLF report message specified in a 3GPP standard document.

[0098] In particular, the RLF report message specified in 3GPP standard document TS38.331 may include the following fields: connectionFailureType, c-RNTI, failedCellId, failedPCellId, failedPCellId-EUTRA, previousPCellId, reestablishmentCellId, rlf-Cause, ssbRLMConfigBitmap, timeConnFailure, and timeSinceFailure.

[0099] 8 shows a flowchart of a method for a failure reporting procedure according to some embodiments of the present application. The method 800 shown in FIG. 8 may be performed by a UE (e.g., the UE 601a shown in FIG. 6).

[0100] 8, in operation 802, the UE may receive an RRC reconfiguration message including a reconfiguration with a synchronization IE and DAPS configuration information. In operation 804, the UE may perform a DAPS handover procedure. In the case of an RLF of a source link for an MCG during the DAPS handover procedure, after successfully completing the DAPS handover procedure, the UE may transmit an RLF report related to the RLF, as shown in operation 806.

[0101] For example, the UE sends an RLF report message to a target BS (e.g., BS 602b shown and illustrated in FIG. 6). In some embodiments of the present application, the RLF report message may include at least one of the following new information: (a) A new indication for successful completion of the DAPS handover procedure. For example, the indication can be set as "Successful DAPS Handover". This new indication indicates that the DAPS handover procedure has been completed successfully, rather than "Failed". Otherwise, the network will consider that a handover failure has occurred during the DAPS handover procedure. b) The previous cell identifier (ID), i.e., the cell ID of the source cell. c) Connection Failure Type: The connection failure type is configured as RLF at the source. d) The cause of the RLF of the source link. This cause can be set to one of the following: (1) Expiration of a physical layer problem timer, (2) Problems with random access procedures, (3) reaching the maximum number of retransmissions; (4) failure of beam failure recovery procedures; (5) expiration of a timer for initiating fault recovery based on triggering a measurement report; (6) receiving a backhaul (BH) RLF indication; and (7) LBT's failure to source link. For example, the RLF report message may include the cause of the RLF of the source link, which is one of t310-Expiry, randomAccessProblem, rlc-MaxNumRetx, beamFailureRecoveryFailure, t312-Expiry, receipt of a BH RLF indication, and mcg-lbtFailure, as specified in the 3GPP standard document.

[0102] FIG. 9 illustrates a further exemplary signaling procedure according to some embodiments of the present application.

[0103] As shown in Figure 9, in operation 901, a target BS (e.g., BS 602b shown in Figure 6) sends a message related to the failure of an MCG to a source BS (e.g., BS 602a shown in Figure 6). The source BS controls the original serving cell of a UE (e.g., UE 101a shown in Figure 1). The target BS controls the target cell of the UE.

[0104] For example, the target BS sends a failure indication message to the source BS. This failure indication message is sent by the target BS to indicate the receipt of an RRC re-establishment attempt or an RLF report from a UE that experienced a connection failure at the source BS. The purpose of sending the failure indication message is to transfer information about the RRC re-establishment attempt or the received RLF report between NG-RAN nodes. Signaling is performed from the target BS where the re-establishment attempt was made or the RLF report was received to the source BS where the involved UE may have been attached before the connection failure. This can help with RLF detection.

[0105] The failure indication message in operation 901 may be a FAILURE INDICATION message defined in a 3GPP standard document. The FAILURE INDICATION message may be sent via an Xn interface or an X2 interface.

[0106] In particular, the FAILURE INDICATION specified in the 3GPP standard document TS 38.423

[16] may include the following IEs or group names: Message Type, CHOICE Initiating condition, RRC Reestab, Failure Cell PCI, Reestablishment Cell CGI, C-RNTI, shortMAC-I (optional), UE RLF Report Container (optional), RRC Setup, and UE RLF Report Container.

[0107] The failure indication message sent from the target BS to the source BS is illustrated in Figure 7 and is associated with the RLF report sent from the UE in the illustrated operation 701. For example, the failure indication message includes an RLF report container. The RLF report container may be sent over an Xn interface or an X2 interface.

[0108] 10 shows a further flowchart of a method for a fault indication procedure according to some embodiments of the present application. The method 1000 shown in FIG. 10 may be performed by a target BS (BS 602b shown and illustrated in FIG. 6 and the target BS shown and illustrated in FIG. 9).

[0109] As shown in Figure 10, in operation 1002, the target BS sends a UE information request. In operation 1004, the target BS receives a UE information response including an RLF report. The RLF report includes information related to the RLF of the source link for the MCG during the DAPS handover procedure. In one embodiment of the present application, the RLF report may include at least one of an indication regarding the successful completion of the DAPS handover procedure, a cell identifier of the source cell, a connection failure type, and a cause of the RLF of the source link. The connection failure type may be configured as RLF at the source.

[0110] In operation 1006, the target BS transmits a failure indication. The failure indication may include an IE related to successful completion of the DAPS handover procedure. For example, the failure indication includes an indication set as "successful DAPS handover."

[0111] In some embodiments of the present application, the failure indication sent in operation 1004 may include at least one of the following IEs: a cell ID of the source cell, a cell ID of the target cell, a cause of the RLF of the source link, a container including the RLF report IE reported from the UE, and a cell radio network temporary identifier (C-RNTI) at the source.

[0112] In some embodiments of the present application, the cause of the RLF of the source link in the failure indication may be one of the following: a) Expiration of a physical layer problem timer, b) Random access procedure issues; c) Reaching the maximum number of retransmissions in the Radio Link Control (RLC); d) Failure of beam failure recovery procedures; e) expiry of a timer for initiating fault recovery based on triggering a measurement report; f) Receipt of BH RLF indications, and g) Listen-Before-Talk (LBT) failures regarding source links It includes at least one of the following:

[0113] In some embodiments of the present application, the cell ID of the target cell in the failure indication is a physical cell identifier (PCI) or an evolved universal terrestrial radio access network (E-UTRAN) cell global identifier (ECGI).

[0114] The following text describes a specific embodiment 3 of the method shown and illustrated in FIGS. 7-10 for solving the above problem.

[0115] According to embodiment 3, a UE (for example, the UE 601a shown and illustrated in FIG. 6) and a target BS (for example, the BS 602b shown and illustrated in FIG. 6) perform the following operations. (1) When a UE is performing a DAPS handover procedure, an RLF may occur at the source. After the DAPS handover procedure is successfully completed, the UE accesses the target cell. (2) The UE sends an rlf-InfoAvailable indication to the target BS. (3) After receiving the instruction from the UE, the target BS sends a UE information request to the UE. (4) After receiving the UE information request from the target BS, the UE sends a UE information response including an RLF report to the target BS. The RLF report may include: New indications, e.g., successful DAPS handover procedure. The previous cell ID that can be set as the source cell. · The connection failure type that can be configured as RLF at the source. · The source's RLF cause may be set to one of t310-Expiry, randomAccessProblem, rlc-MaxNumRetx, beamFailureRecoveryFailure, t312-Expiry, receipt of a BH RLF indication, and mcg-lbtFailure. (5) After receiving a UE information response containing the RLF report from the UE, the target BS sends a failure indication to the source BS. The failure indication may include a new IE that may be set as "DAPS Handover Successful". The sub-IEs of the new IE "DAPS Handover Successful" are as follows: Source cell ID, Target Cell ID, e.g. PCI or ECGI, Optional RLF causes, C-RNTI at the source, and UE RLF Report Container It can be one of:

[0116] Details described in all other embodiments of this application (e.g. details of how to solve the coexistence issue of the DAPS handover procedure and the RLF reporting mechanism for MCG) are applicable to the embodiments of Figures 7 to 10. Furthermore, details described in the embodiments of Figures 7 to 10 are applicable to all embodiments of Figures 1 to 6 and 11.

[0117] FIG. 11 illustrates a simplified block diagram of an apparatus 1100 for an enhanced fault reporting mechanism according to some embodiments of the present application.

[0118] In some embodiments, the apparatus 1100 may be the UE 101 shown in FIG. 1 or the UE 601a shown and illustrated in FIG.

[0119] In some other embodiments, the apparatus 1100 may be a target BS, such as BS 602b illustrated and shown in FIG.

[0120] 11 , an apparatus 1100 may include at least one non-transitory computer-readable medium 1102, at least one receiving circuit 1104, at least one transmitting circuit 1106, and at least one processor 1108. In some embodiments of the present application, the at least one receiving circuit 1104 and the at least one transmitting circuit 1106 are integrated into at least one transceiver. The at least one non-transitory computer-readable medium 1102 may have computer-executable instructions stored thereon. The at least one processor 1108 may be coupled to the at least one non-transitory computer-readable medium 1102, the at least one receiving circuit 1104, and the at least one transmitting circuit 1106. The computer-executable instructions may be programmed to implement a method using the at least one receiving circuit 1104, the at least one transmitting circuit 1106, and the at least one processor 1108. The method may be a method according to an embodiment of the present application, for example, the corresponding method shown in FIG. 5A, FIG. 5B, FIG. 8, or FIG.

[0121] Methods according to embodiments of the present application may also be implemented on a programmed processor. However, the controller, flowcharts, and modules may be implemented on a general-purpose or special-purpose computer, a programmed microprocessor or microcontroller and peripheral integrated circuit elements, integrated circuits, hardware electronic or logic circuits such as discrete element circuits, programmable logic devices, etc. In general, any device on which a finite state machine capable of implementing the flowcharts shown in the figures exists may be used to implement the processor functions of the present application. For example, one embodiment of the present application provides an apparatus for emotion recognition from speech, including a processor and a memory. Computer-programmable instructions for implementing the method for emotion recognition from speech are stored in the memory, and the processor is configured to execute the computer-programmable instructions to perform the method for emotion recognition from speech. The method may be the method described above or another method according to an embodiment of the present application.

[0122] An alternative embodiment preferably implements a method according to an embodiment of the present application in a non-transitory computer-readable storage medium storing computer-programmable instructions. The instructions are preferably executed by a computer-executable component integrated with the network security system. The non-transitory computer-readable storage medium may be stored on RAM, ROM, flash memory, EEPROM, an optical storage device (CD or DVD), a hard drive, a floppy drive, or any suitable device. The computer-executable component is preferably a processor, although the instructions may alternatively or additionally be executed by any suitable dedicated hardware device. For example, one embodiment of the present application provides a non-transitory computer-readable storage medium having computer-programmable instructions stored thereon. The computer-programmable instructions are configured to implement the method for emotion recognition from speech described above or other methods according to an embodiment of the present application.

[0123] While the present application has been described using specific embodiments thereof, it is apparent that many alternatives, modifications, or variations may be apparent to those skilled in the art. For example, various components of the embodiments may be interchanged, added, or substituted in other embodiments. Also, not all elements in each figure are necessary for the operation of the disclosed embodiments. For example, one skilled in the art of the disclosed embodiments will be able to make and use the teachings of the present application by simply using the elements of the independent claims. Accordingly, the embodiments of the present application described herein are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the present application. [Explanation of symbols]

[0124] 100 Wireless Communication System, Dual Connectivity System 101UE 101a UE 102 MN 103SN 600 Wireless Communication System 601 User Equipment (UE), UE 601a UE 602 Base station (BS), BS 602a BS 602b BS 1100 equipment 1102 Non-transitory computer-readable medium 1104 receiving circuit 1106 Transmitting circuit 1108 processor

Claims

1. receiving a radio resource control (RRC) reconfiguration message including a reconfiguration information element (IE) with synchronization and dual active protocol stack (DAPS) configuration information; performing a DAPS handover procedure; In response to a Radio Link Failure (RLF) of a source link with respect to a Master Cell Group (MCG) during the DAPS handover procedure, transmitting an RLF report associated with the RLF after successfully completing the DAPS handover procedure; A method comprising:

2. The RLF report: an indication regarding successful completion of said DAPS handover procedure; The cell identifier (ID) of the source cell, Connection failure type, and The cause of the RLF of the source link including at least one of The method of claim 1.

3. The method of claim 2 , wherein the connection failure type is configured as an RLF at the source.

4. The cause of the RLF of the source link is: Expiration of a physical layer problem timer, Random access procedure issues, Reaching the maximum number of retransmissions, beam failure recovery procedure failure; expiration of a timer for initiating fault recovery based on triggering a measurement report; Receipt of a backhaul (BH) RLF indication, and Source Link (Listen Before Talk) LBT issues including at least one of The method of claim 2.

5. sending a user equipment (UE) information request; receiving a UE information response including a Radio Link Failure (RLF) report, the RLF report including information related to a Radio Link Failure (RLF) of a source link with respect to a Master Cell Group (MCG) during a Dual Active Protocol Stack (DAPS) handover procedure; sending a failure indication, the failure indication including an information element (IE) regarding successful completion of the DAPS handover procedure; A method comprising:

6. The RLF report: an indication regarding successful completion of said DAPS handover procedure; The cell identifier (ID) of the source cell, Connection failure type, and The cause of the RLF of the source link including at least one of The method of claim 5.

7. at least one non-transitory computer-readable medium having computer-executable instructions stored thereon; at least one receiving circuit; at least one transmit circuit; at least one processor coupled to the at least one non-transitory computer-readable medium, the at least one receiving circuit, and the transmitting circuit; An apparatus comprising: The computer-executable instructions cause the at least one processor to implement the method of any one of claims 1 to 4. Device.

8. at least one non-transitory computer-readable medium having computer-executable instructions stored thereon; at least one receiving circuit; at least one transmit circuit; at least one processor coupled to the at least one non-transitory computer-readable medium, the at least one receiving circuit, and the transmitting circuit; An apparatus comprising: The computer-executable instructions cause the at least one processor to implement the method of claim 5 or 6. Device.

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