Terminal device and method performed by the terminal device

Abstract

Embodiments of this disclosure provide a solution for a self-organizing network (SON). In this solution, terminal devices associated with a master cell group (MCG) of a master node (MN) and a secondary cell group (SCG) of a secondary node (SN) detect an MCG failure, and in response to the detection of an MCG failure, initiate an MCG recovery procedure via the SCG, and during the MCG recovery procedure, in response to the detection that the SCG is unavailable, store an appropriate configuration for a radio link failure (RLF) report.

Description

Technical Field

[0001] Exemplary embodiments of the present disclosure generally relate to the field of communication technologies, and more particularly, to apparatuses and methods for a Self Organising Network (SON).

Background Art

[0002] Wireless communication networks have been widely introduced and can support various types of service applications for terminal devices. To improve the performance of communication networks, many communication methods have been proposed. For example, to support the deployment of systems and the optimization of performance, SON technology that covers network self-configuration and self-optimization solutions has been introduced.

[0003] Also, during operation, some kind of failure may occur in both the terminal device and the network device, and the communication in progress may be interrupted. And both the terminal device and the network device may trigger some operations to recover from the failure. Furthermore, to quickly recover from the failure and efficiently reduce the probability of future failures, both the terminal device and the network device may store useful and available related operation information. During the execution of master cell group (MCG) recovery procedures, small data transmission (SDT) procedures, or cell change / addition procedures, the related operation information is not properly stored and reported, which affects the performance improvement of the network device.

Summary of the Invention

Problems to be Solved by the Invention

[0004] Generally, embodiments of the present disclosure provide a method, an apparatus, and a computer storage medium for SON.

Means for Solving the Problems

[0005] In a first embodiment, a terminal device is provided, the terminal device including a processor configured to detect an MCG failure in a terminal device associated with a Master Node (MN) MCG and a Secondary Node (SN) Secondary Cell Group (SCG), to initiate an MCG recovery procedure via the SCG in response to the detection of an MCG failure, and to store a first configuration for a Radio Link Failure (RLF) report in response to the detection of an SCG unavailability during the MCG recovery procedure, wherein the first information includes at least one identifier of at least one primary cell of at least one SCG that previously serviced the terminal device, an identifier of the primary cell of the SCG, a first time period from the time the last reconfiguration with synchronization was performed on the SCG to the time the SCG is detected as unavailable, a second time period from the time the MCG failure was detected to the time the SCG is detected as unavailable, or random access (RA) related information associated with the SCG.

[0006] In a second embodiment, a terminal device is provided, which includes a processor configured to cause the terminal device associated with the MCG of MN and the SCG of SN to detect an MCG failure, to initiate an MCG recovery procedure in response to the detection of an MCG failure, and to transmit second information including at least one identifier of at least one primary cell (PCell) of at least one MCG that previously serviced the terminal device, an identifier of the PCell of the MCG, a third time length from the time the last handover procedure was performed to the time the MCG failure was detected, or RA-related information associated with the MCG.

[0007] In a third aspect, a network device is provided, which includes a processor configured to cause the network device to receive from terminal devices associated with the MCG of MN and the SCG of SN the second information, which includes at least one identifier of at least one primary cell (PCell) of each of the at least one MCG that previously provided service to the terminal devices, the identifier of the PCell of the MCG, a third time length from the time the last handover procedure is performed until the time an MCG failure is detected, or RA-related information associated with the MCG.

[0008] In a fourth aspect, a terminal device is provided, the terminal device includes a processor configured to cause the terminal device to generate an RA report for an RA procedure, which is associated with a Small Data Transmission (SDT), and to cause the terminal device to send the RA report to a network device, the RA report comprising at least one of the following: a second instruction indicating that the RA procedure is associated with an SDT; a third instruction indicating that the RA procedure was successful; a fourth instruction indicating that the RA procedure failed; a fifth instruction indicating that the RA procedure is triggered during a subsequent transmission of the SDT; or a sixth instruction indicating that the RA procedure is triggered during the first transmission of the SDT.

[0009] In a fifth embodiment, a network device is provided, the network device including a processor configured to cause the network device to receive RA reports of RA procedures from a terminal device, the RA report being associated with an SDT and including at least one of a second instruction indicating that the RA procedure is associated with an SDT, a third instruction indicating that the RA procedure was successful, a fourth instruction indicating that the RA procedure failed, a fifth instruction indicating that the RA procedure is triggered during a subsequent transmission of the SDT, or a sixth instruction indicating that the RA procedure is triggered during the initial transmission of the SDT.

[0010] In a sixth aspect, a terminal device is provided, which includes a processor configured to receive a Successful PSCell Change / Addition Report (SPR) configuration from a network device, store SPR information according to the SPR configuration in accordance with the successful completion of a PSCell change or addition procedure, and to release the SPR configuration or discard the SPR information when it detects at least one of the following: release of the SCG, completion of a handover procedure, commencement of a Radio Resource Control (RRC) connection re-establishment procedure, commencement of an RRC connection re-activation procedure, or successful completion of a PSCell change or addition procedure.

[0011] A seventh aspect provides a communication method performed by a terminal device. This method includes, in a terminal device associated with an MCG of an MN and an SCG of an SN, detecting an MCG failure, initiating an MCG recovery procedure via the SCG in response to the detection of the MCG failure, and, during the MCG recovery procedure, storing a first configuration for an RLF report in response to the detection that the SCG is unavailable, wherein the first configuration includes at least one identifier of at least one primary cell of at least one SCG that previously serviced the terminal device, an identifier of the primary cell of the SCG, a first time length from the time the last reconfiguration with synchronization was performed on the SCG to the time the SCG is detected as unavailable, a second time length from the time the MCG failure was detected to the time the SCG is detected as unavailable, or RA-related information associated with the SCG.

[0012] In the eighth aspect, a communication method is provided that is performed by a terminal device. This method includes, in a terminal device associated with an MCG of an MN and an SCG of an SN, detecting an MCG failure, initiating an MCG recovery procedure in response to the detection of the MCG failure, and transmitting a second piece of information including at least one identifier of at least one primary cell (PCell) of at least one MCG that previously serviced the terminal device, the PCell identifier of the MCG, a third time length from the time the last handover procedure was performed to the time the MCG failure was detected, or RA-related information associated with the MCG.

[0013] In a ninth aspect, a communication method is provided that is performed by a network device. This method includes receiving second information from terminal devices associated with the MCG of the MN and the SCG of the SN, which includes at least one identifier of at least one PCell that previously served the terminal device, an identifier of the PCell of the MCG, a third time period from the time the last handover procedure is performed to the time when a failure of the MCG is detected, or RA-related information associated with the MCG.

[0014] In a tenth aspect, a communication method is provided which is performed by a terminal device. This method includes generating an RA report for an RA procedure, the RA report including at least one of a second instruction indicating that the RA procedure is associated with an SDT, a third instruction indicating that the RA procedure was successful, a fourth instruction indicating that the RA procedure failed, a fifth instruction indicating that the RA procedure is triggered during a subsequent transmission of the SDT, or a sixth instruction indicating that the RA procedure is triggered during the initial transmission of the SDT, and transmitting the RA report to a network device.

[0015] In an eleventh aspect, a communication method is provided that is performed by a network device. This method includes receiving an RA report of an RA procedure from a terminal device, the RA report including at least one of a second instruction indicating that the RA procedure is associated with an SDT, a third instruction indicating that the RA procedure was successful, a fourth instruction indicating that the RA procedure failed, a fifth instruction indicating that the RA procedure is triggered during a subsequent transmission of the SDT, or a sixth instruction indicating that the RA procedure is triggered during the initial transmission of the SDT.

[0016] In a twelfth aspect, a communication method is provided that is performed by a terminal device. This method includes receiving a normal PSCell change / addition report (SPR) configuration from a network device; storing SPR information according to the SPR configuration in response to the successful completion of a PSCell change or addition procedure; and releasing the SPR configuration or discarding the SPR information when detecting at least one of the following: release of the SCG, completion of a handover procedure, commencement of an RRC connection re-establishment procedure, commencement of an RRC connection restart procedure, or successful completion of a PSCell change or addition procedure.

[0017] In the thirteenth aspect, a computer-readable medium containing instructions is provided, and when the instructions are executed on at least one processor, the instructions cause at least one processor to perform the method according to the first, second, third, fourth, fifth, or sixth aspect.

[0018] Other features of this disclosure will be readily apparent through the following description. [Brief explanation of the drawing]

[0019] The above and other objectives, features and advantages of this disclosure will become more apparent through a more detailed description of some exemplary embodiments of this disclosure in the accompanying drawings.

[0020] [Figure 1A]An exemplary communication environment in which some embodiments of the present disclosure can be implemented is shown.

[0021] [Figure 1B] Another exemplary communication environment in which some embodiments of the present disclosure can be implemented is shown.

[0022] [Figure 2] A signaling flow for communication according to some embodiments of the present disclosure is shown.

[0023] [Figure 3] Another signaling flow for communication according to some embodiments of the present disclosure is shown.

[0024] [Figure 4] A further signaling flow for communication according to some embodiments of the present disclosure is shown.

[0025] [Figure 5] A flowchart of a method implemented by a terminal device according to some exemplary embodiments of the present disclosure is shown.

[0026] [Figure 6] A flowchart of a method implemented by a terminal device according to some exemplary embodiments of the present disclosure is shown.

[0027] [Figure 7] A flowchart of a method implemented by a network device according to some exemplary embodiments of the present disclosure is shown.

[0028] [Figure 8] A flowchart of a method implemented by a terminal device according to some exemplary embodiments of the present disclosure is shown.

[0029] [Figure 9] A flowchart of a method implemented by a network device according to some exemplary embodiments of the present disclosure is shown.

[0030] [Figure 10] A flowchart shows a method implemented in a terminal device according to some exemplary embodiments of the present disclosure.

[0031] [Figure 11] A simplified block diagram of an apparatus suitable for carrying out exemplary embodiments of the present disclosure is shown.

[0032] Throughout the drawing, identical or similar reference numbers represent identical or similar elements. [Modes for carrying out the invention]

[0033] The principles of this disclosure will now be illustrated with reference to several exemplary embodiments. These embodiments are provided for illustrative purposes only and should be understood as being helpful to those skilled in the art in understanding and implementing this disclosure, without implying any limitation on the scope of this disclosure. The embodiments described herein can be implemented in a variety of ways other than those described below.

[0034] In the following description and claims, unless otherwise defined, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art to which this disclosure belongs.

[0035] As used herein, the term “terminal device” refers to any device equipped with wireless or wired communication capabilities. Examples of terminal devices include user equipment (UE), personal computers, desktops, mobile phones, cellular phones, smartphones, personal digital assistants (PDAs), portable computers, tablets, wearable devices, Internet of Things (IoT) devices, Ultra-Reliable and Low Latency Communications (URLLC) devices, Internet of Everything (IoE) devices, Machine Type Communication (MTC) devices, Vehicle-mounted devices for V2X communication (where X represents pedestrians, vehicles, or infrastructure / networks), Integrated Access and Backhaul (IAB) devices, spacecraft or aerial vehicles within non-terrestrial networks (NTN) including high-altitude platforms (HAP) with satellites and unmanned aircraft systems (UAS), Augmented Reality (AR), Mixed Reality (MR) Examples include, but are not limited to, extended reality (XR) devices, which include various types of reality such as reality and virtual reality (VR); unmanned aerial vehicles (UAVs), which are aircraft without human pilot intervention, commonly known as drones; equipment mounted on high-speed trains (HSTs); image capture devices such as digital cameras, sensors, game consoles, and music storage and playback devices; or internet equipment that enables wireless or wired internet access and browsing.A “terminal device” can also have “multicast / broadcast” capabilities and support public safety and mission-critical, V2X applications, transparent IPv4 / IPv6 multicast distribution, IPTV, smart TV, radio services, software distribution over the radio, group communications, and IoT applications. It may also incorporate one or more Subscriber Identity Modules (SIMs), known as multi-SIMs. The term “terminal device” may be used interchangeably with UE, mobile station, subscriber station, mobile terminal, user terminal, or radio equipment.

[0036] The term "network device" refers to a device that can provide or host a cell or coverage from which terminal devices can communicate. Examples of network devices include, but are not limited to, Node B (NodeB or NB), evolved Node B (eNodeB or eNB), next-generation Node B (gNB), transmission / reception point (TRP), remote radio unit (RRU), radio head (RH), remote radio head (RRH), IAB node, low-power nodes such as femtonodes, piconodes, and reconfigurable intelligent surface (RIS).

[0037] Terminal devices or network devices may be equipped with artificial intelligence (AI) or machine learning capabilities. These typically include models trained on large amounts of collected data for specific functions, which can then be used to predict certain information.

[0038] Terminal or network devices can operate in multiple frequency ranges, including FR1 (e.g., 450 MHz to 6000 MHz), FR2 (e.g., 24.25 GHz to 52.6 GHz), frequency bands above 100 GHz, and terahertz (THz). Furthermore, they can operate in licensed / unlicensed / shared spectrum. In multi-radio dual connectivity (MR-DC) application scenarios, terminal devices may have multiple connections to network devices. Terminal or network devices can operate in full-duplex, flexible-duplex, and cross-split-duplex modes.

[0039] Embodiments of this disclosure can be implemented using test equipment such as signal generators, signal analyzers, spectrum analyzers, network analyzers, test terminal devices, test network devices, and channel emulators. In some embodiments, the terminal device may be connected to a first network device and a second network device. One of the first and second network devices may be a master node and the other a secondary node. The first and second network devices may use different radio access technologies (RATs). In some embodiments, the first network device may be a first RAT device, and the second network device may be a second RAT device. In some embodiments, the first RAT device is an eNB, and the second RAT device is a gNB. Information related to different RATs may be transmitted from at least one of the first or second network devices to the terminal device. In some embodiments, the first information may be transmitted from the first network device to the terminal device, and the second information may be transmitted directly from the second network device to the terminal device or via the first network device. In some embodiments, information regarding the configuration of a terminal device set by the second network device may be transmitted from the second network device through the first network device. Information regarding the reconfiguration of a terminal device set by the second network device may be transmitted directly from the second network device to the terminal device or through the first network device.

[0040] Where used herein, the singular forms “a / an” and “the” are intended to include the plural unless explicitly indicated otherwise in the context. The term “including” and its variations are interpreted as an open term meaning “including, but not limited to.” The term “based on” is interpreted as “at least partially based on.” The terms “one embodiment” and “a certain embodiment” are interpreted as “at least one embodiment.” The term “another embodiment” is interpreted as “at least one other embodiment.” Terms such as “first,” “second,” etc., may refer to different or the same subject. The following may include other explicit and implicit definitions.

[0041] In some examples, values, procedures, or devices are referred to as “best,” “worst,” “highest,” “minimum,” “maximum,” etc. Such descriptions are intended to show that a choice can be made from among many functional options being used, and it will be understood that such a choice does not need to be better, smaller, higher, or more preferable than the other options.

[0042] As used herein, the terms “resource,” “transmit resource,” “uplink resource,” or “downlink resource” may refer to any resource for performing communication, such as a resource in the time domain, a resource in the frequency domain, a resource in the spatial domain, a resource in the code domain, or any other resource that enables communication. Hereinafter, unless expressly stated otherwise, resources in both the frequency domain and the time domain are used as examples of transmit resources to illustrate some exemplary embodiments of this disclosure. The exemplary embodiments of this disclosure are similarly applicable to other resources in other domains.

[0043] As explained above, SON technology, which encompasses self-configuration and self-optimization solutions for networks, is implemented to support system deployment and performance optimization.

[0044] Furthermore, during operation, a failure may occur in both the terminal device and the network device, potentially interrupting pending communications, and both the terminal device and the network device may trigger some action to recover from the failure. In addition, to recover quickly from failures and efficiently reduce the probability of future failures, both the terminal device and the network device may store relevant operational information that is useful and available.

[0045] As mentioned above, conventional solutions fail to properly store and report relevant operational information during certain procedures such as MCG recovery procedures, SDT, or cell changes / additions, impacting the performance of network devices.

[0046] Embodiments of this disclosure provide SON solutions. According to some embodiments of the present invention, the operation of terminal and network devices during procedures such as MCG recovery procedures, SDT, or cell modification / addition is appropriately defined. Accordingly, network performance is improved.

[0047] The principles and embodiments of this disclosure are described in detail below with reference to the drawings.

[0048] In this specification, the terms "SCG pause" and "SCG deactivation" are used interchangeably.

[0049] In this specification, the terms "MCG recovery" and "fast MCG recovery" are used interchangeably. <Example of a communication network>

[0050] Figure 1A shows an exemplary communication environment 100 in which exemplary embodiments of the present disclosure can be implemented. The network communication 100 includes a terminal device 110, a network device 120-1, and optional network devices 120-2 and 120-3. In the following text, network devices 120-1, 120-2, and 120-3 will be referred to collectively as network device 120 or individually as network device 120. Network device 120 may also provide one or more coverage areas. Furthermore, each network device 120-1 may provide one or more respective coverage areas (not shown, also referred to as cells in the following text), and if the terminal device is in a cell, the terminal device 110 may have access to network device 120.

[0051] In the communication environment 100, the link from terminal device 110 to network device 120 is called an uplink, and the link from network device 120 to terminal device 110 is called a downlink. In a downlink, network device 120 is a transmitting (TX) device (or transmitter), and terminal device 110 is a receiving (RX) device (or receiver). In an uplink, terminal device 110 is a TX device (or transmitter), and network device 120 is an RX device (or receiver).

[0052] In the specific example shown in Figure 1A, the terminal device 110 may be in different states (e.g., connected, inactive, idle). When the terminal device 110 is in the connected state, it can transmit data from all wireless bearers. Furthermore, in some embodiments, when the terminal device 110 is in the idle state, it typically cannot perform any data transmission. Also, when the terminal device 110 is in the inactive state, SDT is supported while the transmission of data set for SDT is permitted during the SDT procedure.

[0053] Furthermore, in the example shown in Figure 1A, the terminal device 110 may move over time. As shown in Figure 1A, the terminal device 110 is in a different position at different points in time (T1 and T2). In addition, the channel conditions may also be changed dynamically. As a result, the connection relationship between the terminal device 110 and the second device 120 may be changed dynamically, and related cells may be added / modified / deleted.

[0054] In some embodiments, the terminal device 110 may operate in dual connectivity mode. In dual connectivity mode, the terminal device may be configured to utilize wireless resources provided by two network devices 120. In the specific embodiment shown in Figure 1A, the terminal device 120 may be serviced by both network devices 120-1 and 120-2.

[0055] To better understand the dual connectivity mode, refer to Figure 1B, which shows a specific exemplary communication environment 140 in which exemplary embodiments of the present disclosure can be implemented. For illustrative purposes, refer to Figure 1A to describe a communication environment 150.

[0056] In the example shown in Figure 1B, network devices 120-1 and 120-2 are deployed to provide services to terminal device 110. Network device 120-1 provides services to terminal device 110 as an MN (Mobile Network Manager), and network device 120-2 provides services to terminal device 110 as an SN (Network Service Provider).

[0057] As shown in Figure 1B, the cell group of network device 120-1 includes primary cell 150-1 and secondary cell 150-2. Since network device 120-1 provides services as an MN, the cell group of network device 120-1 is called MCG150, and primary cell 150-1 is also called PCell150-1.

[0058] The group of cells in network device 120-2 includes primary cell 160-1 and secondary cell 160-2. Since network device 120-2 provides services as an SN, the group of cells in network device 120-2 is called SCG160. PCell 150-1 of MCG150 or primary cell 160-1 of SCG160 may be called SpCell. Furthermore, SpCell of SCG160 (i.e., primary cell 160-1 of SCG160) may be called PSCell.

[0059] Similar to the discussion with respect to Figure 1A, the relationships between terminal device 110 and MN (i.e., network device 120-1), SN (i.e., network device 120-2), MCG, SCG, primary cell, etc., may be dynamically changed depending on the specific communication scenario.

[0060] In this disclosure, the functionality of high-speed MCG recovery is supported for Mobility Robustness Optimization (MRO). Furthermore, if T316 expiration or SCG failure / deactivation is detected during high-speed MCG recovery, the terminal device 110 determines that high-speed MCG recovery has failed. In addition, during the high-speed MCG recovery procedure, the terminal device can store information for RLF reporting.

[0061] The number of devices and their connections shown in Figures 1A and 1B are for illustrative purposes only and should not be considered as limitations. Communication environments 100 and 140 may include any appropriate number of devices configured to carry out exemplary embodiments of this disclosure. It will be understood that communication environment 100 may have one or more additional devices, although not shown. Note that network device 120 is shown as a network device, but may be a device other than a network device. Terminal device 110 is shown as a terminal device, but may be a device other than a terminal device.

[0062] In the following, for the sake of clarity, several exemplary embodiments will be described in which the terminal device 110 operates as a UE and the network device 120 operates as a base station. However, in some exemplary embodiments, the operations described in relation to the terminal device may be performed by the network device or other devices, and the operations described in relation to the network device may be performed by the terminal device or other devices.

[0063] Communication in communication environment 100 includes, but is not limited to, Global System for Mobile Communications (GSM), Long Term Evolution (LTE), LTE Evolution, LTE-Advanced (LTE-A), New Radio (NR), Wideband Code Division Multiple Access (WCDMA), Code Division Multiple Access (CDMA), GSM Edge Radio Access Network (GERAN), Machine Type Communication (MTC), and can comply with any appropriate standard. Embodiments of this disclosure may be implemented in accordance with any generation of communication protocol that is currently known or will be developed in the future. Examples of communication protocols include, but are not limited to, first-generation (1G), second-generation (2G), 2.5G, 2.75G, third-generation (3G), fourth-generation (4G), 4.5G, fifth-generation (5G) communication protocols, 5.5G, 5G-Advanced Network, or sixth-generation (6G) networks. <Example of a process>

[0064] While functions / operations are described individually in certain exemplary embodiments, it should be understood that these functions / operations described in different exemplary embodiments may be used in any appropriate combination unless explicitly stated otherwise. Exemplary Process for MCG Recovery Procedures

[0065] In conventional solutions, upon detecting an MCG failure, the UE may initiate timer T316 and report the MCG failure to the MN via the SCG with an MCGFailureInformation message. In some scenarios, even if an MCG failure occurs, a downlink transmission from the MN may also occur, meaning the UE may receive a first instruction (e.g., scg-State) to deactivate the SCG while timer T316 is running. Furthermore, the UE may detect an SCG failure while timer T316 is running. In other words, the SCG may be deactivated or fail during the MCG recovery procedure. Conventional solutions cannot specify the appropriate behavior of the UE and / or network equipment in the above scenarios.

[0066] According to the exemplary embodiments described below, if an SCG failure / deactivation is detected during MCG recovery, the SCG history (particularly information related to failures in the MCG recovery procedure) is appropriately stored (for example, in the VarRLF-Report).

[0067] Refer to Figure 2, which shows a signaling flow 200 for communication according to some embodiments of the present disclosure. For convenience of explanation, the signaling flow 200 will be described using, for example, terminal device 110 and network devices 120-1 and 120-2 with reference to Figures 1A and 1B.

[0068] In the specific embodiment shown in Figure 2, the terminal device 110 operates in dual connectivity mode and is configured to utilize the wireless resources of both network devices 120-1 and 120-2.

[0069] Furthermore, network device 120-1 provides services to terminal device 110 as MN, and network device 120-2 provides services to terminal device 110 as SN, meaning that terminal device 110 is associated with MCG150 and SCG160. In the following text, network device 120-1 may also be referred to as MN120-1, and network device 120-1 may also be referred to as SN120-2.

[0070] During operation, terminal device 110 detects a failure in MCG150 (210). It should be understood that there are several possible reasons for an MCG150 failure, including, but not limited to, the detection of an RLF failure in MCG150 or the reception of a switchover message from MCG150. In summary, an MCG failure prevents uplink transmission to network device 120-1.

[0071] If the MCG150 fails, the terminal device 110 initiates the MCG recovery procedure via the SCG160 (230). Furthermore, in some embodiments, the terminal device 110 may send a message indicating the MCG150 failure (e.g., an MCGFailureInformation message) to the network device 120-2 (232), and the network device 120-2 may forward this message to the network device 120-1 (234).

[0072] Furthermore, in some embodiments, the terminal device 110 may start a timer (i.e., timer T316) to control the MCG recovery procedure (220).

[0073] Next, during the MCG recovery procedure, terminal device 110 may detect that SCG 160 is unavailable (240). In some embodiments, SCG 160 may be unavailable due to receiving a first instruction (e.g., scg-State) from network device 120-1 to deactivate SCG 160 (244) (as previously stated, downlink transmissions from network device 120-1 may proceed even if MCG 150 fails). Alternatively, network device 120-1 may also transmit the first instruction via network device 120-2. In summary, terminal device 110 may receive a first instruction to deactivate SCG 160 during the MCG recovery procedure, and the receipt of the first instruction may cause SCG 160 to become unavailable.

[0074] In other embodiments, the unavailability of SCG160 may be caused by detecting a fault in the SCG (242). In a particular embodiment, terminal device 110 may perform a wireless link measurement on SCG160 and, based on the measurement results, detect a fault in SCG160.

[0075] In this disclosure, when terminal device 110 detects that SCG 160 is unavailable, terminal device 110 stores first information of the RLF report (260) (for example, stored in VarRLF-Report). According to some embodiments of this disclosure, the first information relates to the history information of SCG 160.

[0076] In some embodiments, the first information may include at least one identifier of at least one primary cell of at least one SCG that previously provided service to the terminal device, i.e., the previous PSCell ID. Such information may help the network identify whether the failure of SCG160 during MCG recovery is caused by a premature PSCell change.

[0077] Alternatively, or further, in some embodiments, the first information may include an identifier for the primary cell of the SCG, i.e., the PSCell ID of the failed cell. Such information may help the network identify whether the failure of SCG160 during MCG recovery is caused to trigger a PSCell change to the wrong PSCell.

[0078] Alternatively, or further, in some embodiments, the first information may include a first time length from the time the last reconfiguration with synchronization is performed on SCG160 (i.e., a change or addition to the PSCell) to the time when SCG160 is detected to be unavailable. Such information may help the network identify timeline information for MCG recovery failures.

[0079] Alternatively, or further, in some embodiments, the first information may include a second time period from the time when an MCG failure is detected to the time when an SCG is detected as unavailable. Such information may help the network identify timeline information for MCG recovery failure.

[0080] Alternatively, or further, in some embodiments, the first information may include RA-related information associated with SCG160. In some embodiments, the RA-related information provides detailed information about each RA procedure attempt in chronological order of the RA attempts. In some embodiments, the RA-related information is the parameter perRAInfoList. Such information may help the network identify RA problems in SCG160 during the MCG recovery procedure.

[0081] Please understand that the above example of the first information is provided for illustrative purposes only. Please understand that any appropriate historical information of SCG160 may be included in the first information. This disclosure is not limited in this respect.

[0082] Furthermore, as explained above, the unavailability of SCG160 may be caused by a failure of SCG160 or by deactivation of SCG160.

[0083] Generally speaking, if SCG160 fails, terminal device 110 may initiate a procedure to re-establish connection with network device 120-2.

[0084] In conventional solutions, if the SCG is deactivated during the MCG recovery procedure, the UE does not initiate the connection re-establishment procedure. However, this behavior is inappropriate because if the SCG is deactivated during the MCG recovery procedure, communication between the UE and the network is interrupted, and the UE experience is reduced accordingly.

[0085] In some embodiments of the present disclosure, similar to the process for handling failures of the SCG 160, when the terminal device 110 receives a first instruction to deactivate the SCG, it may initiate a procedure to re-establish a connection with the network device 120-2 (250).

[0086] The above procedure may be used to properly store the history information of SCG160. The following text describes an example of how to process the history information of MCG150.

[0087] Generally speaking, terminal device 110 may occasionally perform a reconfiguration with synchronization, or it may perform an RRC release procedure if MCG recovery is successful.

[0088] The operations of the terminal device 110 regarding how to perform a reconfiguration with synchronization from time to time are listed below. Specifically, the terminal device 110 may perform the following operations in order to perform a reconfiguration with synchronization. 1> If timer T430 is running, stop it; 1> If included in the serving cell's reconfigurationWithSync, start timer T430 with the timer value set in ntn-UISyncValidityDuration from the subframe indicated by epochTime; 1> If AS security is not activated, perform the action when the procedure ends, transitioning to RRC_IDLE with the release reason "Other"; 1> If the DAPS bearer is not configured: 2> If timer T310 for the corresponding SpCell is running, stop it; 1> If you perform this procedure on MCG: 2> If timer T316 is running; 3> Stop timer T316; 3> If there is any information contained in the VarRLF-Report, delete it; 2> If MCG transmission is paused, resume it.

[0089] The actions of terminal device 110 regarding how to perform the RRC release procedure are listed below. Specifically, terminal device 110 may perform the following actions to release the RRC connection. 1> When the RRCRelease message is received, or optionally when a lower layer confirms that the receipt of the RRCRelease message has been successfully verified. From whichever of the indicated points in time comes first, the following actions as defined in this clause will be delayed by 60ms: 1> If timer T380 is running, stop it; 1> If timer T320 is running, stop it; 1> If timer T316 is running; 2> Stop timer T316; 2> If there is any information contained in the VarRLF-Report, delete it.

[0090] If the MCG150 fails, terminal device 110 may store MCG failure information in the RLF report. Furthermore, if the message reconfigurationWithSync or RRCRelease is received for the MCG150 (which may indicate that the MCG recovery procedure was successful), terminal device 110 stops the T316 timer and discards the RLF report. In other words, if the MCG recovery procedure is successful, terminal device 110 erases the information stored for the RLF report. However, in practice, terminal device 110 may also store the history information of the MCG150, which is useful for improving future network maintenance. For this reason, the stored history information of the MCG150 needs to be provided to the network.

[0091] Refer to Figure 2 here as well. During operation, the terminal device 110 detects a failure in the MCG 150 as described above (210). When a failure occurs in the MCG 150, the terminal device 110 starts the MCG recovery procedure (230).

[0092] In this disclosure, the terminal device 110 further transmits second information relating to the history information of the MCG 150.

[0093] In some embodiments, the second information may include at least one identifier of at least one primary cell (PCell) of at least one MCG that previously provided services to the terminal device.

[0094] Alternatively, or further, in some embodiments, the second information may include an identifier for the PCell of the MCG.

[0095] Alternatively, or further, in some embodiments, the second information may include a third time period from the time the last handover procedure is performed to the time when an MCG failure is detected. Such information may help the network identify whether the failure of MCG150 during the MCG recovery procedure was caused by a premature handover.

[0096] Alternatively, or further, in some embodiments, the second information may include RA-related information associated with MCG150. In some embodiments, the RA-related information provides detailed information about each RA procedure attempt in chronological order of the RA attempts. In some embodiments, the RA-related information is the parameter perRAInfoList. Such information may help the network identify RA problems in MCG150 during MCG recovery.

[0097] Furthermore, in some embodiments, the terminal device 110 transmits RA-related information associated with the MCG only when the MCG failure is caused by an RA failure, i.e., when the MCG failure type is a random access failure problem.

[0098] According to some embodiments of the present invention, the second information may be transmitted to any suitable device via appropriate signaling. In a particular embodiment, the second information is transmitted via MCG failure information used by the terminal device 110 to initiate an MCG recovery procedure.

[0099] Alternatively, in another specific embodiment, the second information is transmitted via a fault report sent in response to the receipt of a request for the second information. In this case, the terminal device 110 may first store the second information and then report the second information to the network if requested by the network. Exemplary Process for SDT Procedures

[0100] This disclosure supports RA-based SDT. The following example shows how the RA-related and SDT information included in the SDT RA report may be further enhanced.

[0101] Refer to Figure 3, which shows a signaling flow 300 for communication according to some embodiments of the present disclosure. For convenience of explanation, the signaling flow 300 will be described using, for example, a terminal device 110 and a network device 120-1 with reference to Figures 1A and 1B.

[0102] During operation, terminal device 110 generates an RA report for the RA procedure, where the RA report is associated with the SDT. Further details regarding the SDT may be reported in the RA report in this disclosure.

[0103] In some embodiments, the RA report includes a second instruction indicating that the RA procedure is associated with an SDT. That is, the RA purpose in the RA report is set to a value indicating an SDT.

[0104] Alternatively, or further, in some embodiments, the RA report includes a third instruction indicating that the RA procedure was successful.

[0105] Alternatively, or further, in some embodiments, the RA report includes a fourth instruction indicating that the RA procedure failed.

[0106] Alternatively, or further, in some embodiments, the RA report includes a fifth instruction indicating that the RA procedure is triggered during a subsequent transmission of the SDT.

[0107] Alternatively, or further, in some embodiments, the RA report includes a sixth indicating that the RA procedure is triggered during the initial transmission of the SDT.

[0108] To ensure rational resource usage, in some embodiments, RA resources (also called RACH resources) are divided according to different functions or combinations of functions. Specifically, the network may associate sets of RA resources with functions applicable to RA procedures. Examples of functions may include network slicing RedCap, SDT, and NR coverage extensions.

[0109] Furthermore, a set of RA resources associated with a particular function is valid only for RA procedures applicable to at least that function, and a set of RA resources associated with multiple functions is valid only for random access procedures that have at least all of these functions. The terminal device 110 may select a set of applicable RA resources after selecting the uplink carrier (i.e., a normal uplink or an auxiliary uplink) and the bandwidth portion (BWP), but before selecting the RA type.

[0110] In some embodiments, if the RA procedure is triggered during the initial transmission of the SDT, the RA report further includes RA splitting information associated with the RA procedure.

[0111] In some embodiments, the RA partitioning information indicates at least one of the following: a function or combination of functions that triggers an RA procedure, or a function or combination of functions that corresponds to an RA resource used by the RA procedure.

[0112] In some embodiments, the RA report is generated upon completion of the SDT. Alternatively, in some embodiments, the RA report is generated upon completion of the RA procedure. In a particular embodiment, if the RA procedure succeeds or fails during the progress of the SDT procedure, the terminal device 110 sets / includes the above information in the ra-InformationCommon of the RA report. An example process related to SPR

[0113] Currently, the SPR configuration may be received by the terminal device 110, where the trigger condition for storing the SPR configuration is indicated in the SPR configuration. In the SPR configuration, the terminal device 110 may store the SRS information when the trigger condition in the SPR configuration is met.

[0114] However, maintaining the SPR configuration and stored SPR information may consume resources. Therefore, the SPR configuration may be released, and the SPR information may be discarded over time. The processes for releasing the SPR configuration and discarding the SPR information are described in detail according to the exemplary embodiments described below.

[0115] Refer to Figure 4, which shows a signaling flow 400 for communication according to some embodiments of the present disclosure. For convenience of explanation, the signaling flow 200 will be described using, for example, a terminal device 110 and a network device 120, with reference to Figures 1A and 1B.

[0116] During operation, terminal device 110 receives the SPR configuration from network device 120 (420). In the specific example in Figure 4, network device 120 is the MN, source SN, or target SN.

[0117] Next, upon successful completion of any modification or addition procedure to the PSCell, the terminal device 110 stores the SPR information according to the SPR configuration (420). In other words, upon successful completion of the random access procedure triggered by the SCG's reconfigurationWithSync, the terminal device 110 stores the SPR information according to the SPR configuration (420).

[0118] According to some embodiments of the present invention, the operation to release the SPR configuration may be triggered by a specific event. One example of an event is the release of the SCG. Another example of an event is the completion of a handover procedure. Further examples of events include the initiation of an RRC connection re-establishment procedure, the initiation of an RRC connection restart procedure, and the successful completion of a PSCell modification or addition procedure.

[0119] In some embodiments, if the operation to release the SPR configuration is triggered by the release of the SCG or the successful completion of a PSCell modification or additional procedure, the terminal device 110 releases only the SPR configuration received from the source SN or target SN.

[0120] According to some embodiments of the present invention, the action of discarding SPR information may also be triggered by certain events. One example of an event is the release of the SCG. Another example of an event is the completion of a handover procedure. Further examples of events include the initiation of an RRC connection re-establishment procedure and the initiation of an RRC connection restart procedure. <Example of method>

[0121] Figure 5 shows a flowchart of a communication method 500 implemented in a terminal device according to several embodiments of the present disclosure. For convenience of explanation, the method 500 will be described in terms of the terminal device 110 shown in Figures 1A and 1B.

[0122] In block 510, terminal devices 110 detect MCG failures in terminal devices 110 associated with the master cell group (MCG) of the master node (MN) and the secondary cell group (SCG) of the secondary node (SN).

[0123] In block 520, the terminal device 110 initiates an MCG recovery procedure via the SCG in response to the detection of an MCG failure.

[0124] In block 530, in response to detection that the SCG is unavailable during the MCG recovery procedure, the terminal device 110 stores a first configuration for a radio link failure (RLF) report, the first information in block 540 includes at least one identifier of at least one primary cell of at least one SCG that previously served the terminal device 110, the identifier of the primary cell of the SCG, a first time period from the time the last reconfiguration with synchronization was performed on the SCG to the time the SCG is detected as unavailable, a second time period from the time the MCG failure is detected to the time the SCG is detected as unavailable, or random access (RA) related information associated with the SCG.

[0125] In some exemplary embodiments, the terminal device 110 detecting that the SCG is unavailable includes at least receiving a first instruction from the master node to deactivate the SCG, or detecting a failure in the SCG.

[0126] In some exemplary embodiments, upon receiving a first instruction, the terminal device 110 initiates a procedure to re-establish a connection with the secondary node.

[0127] Figure 6 shows a flowchart of a communication method 600 implemented in a terminal device 110 according to several embodiments of the present disclosure. For convenience of explanation, the method 600 will be described in terms of the terminal device 110 shown in Figures 1A and 1B.

[0128] In block 610, terminal devices 110 detect MCG failures in terminal devices 110 associated with the master cell group (MCG) of the master node (MN) and the secondary cell group (SCG) of the secondary node (SN).

[0129] In block 620, upon detection of an MCG failure, terminal device 110 initiates an MCG recovery procedure and transmits second information including at least one identifier of at least one primary cell (PCell) of each of the at least one MCGs that previously served terminal device 110, the PCell identifier of the MCG, a third time period from the time the last handover procedure was performed to the time the MCG failure was detected, or random access (RA) related information associated with the MCG.

[0130] In some exemplary embodiments, transmitting RA-related information associated with the MCG includes transmitting RA-related information associated with the MCG when the MCG failure is caused by an RA failure.

[0131] In some exemplary embodiments, transmitting the second information includes transmitting the second information via one of the following: MCG failure information used by the terminal device 110 to initiate an MCG recovery procedure, or a failure report transmitted in response to the receipt of a request for the second information.

[0132] Figure 7 shows a flowchart of a communication method 700 implemented in a network device 120 according to several embodiments of the present disclosure. For convenience of explanation, the method 700 will be described in terms of the network device 120 shown in Figures 1A and 1B.

[0133] In block 710, the network device 120 receives second information from terminal devices 110 associated with the master cell group (MCG) of the master node (MN) and the secondary cell group (SCG) of the secondary node (SN), which includes at least one identifier of at least one primary cell (PCell) of each MCG that previously served the terminal devices 110, the PCell identifier of the MCG, a third time period from the time the last handover procedure was performed to the time an MCG failure was detected, or random access (RA) related information associated with the MCG.

[0134] In some exemplary embodiments, RA-related information indicates RA failure information.

[0135] In some exemplary embodiments, the network device 120 is an MN, and receiving the second information includes receiving MCG failure information containing the second information from the terminal device 110, which is used by the terminal device 110 to initiate an MCG recovery procedure.

[0136] In some exemplary embodiments, the processor is further configured to send a request for a second piece of information to the terminal device 110 via the network device 120.

[0137] Figure 8 shows a flowchart of a communication method 800 implemented in a terminal device 110 according to several embodiments of the present disclosure. For convenience of explanation, the method 800 will be described in terms of the terminal device 110 shown in Figures 1A and 1B.

[0138] In block 810, the terminal device 110 generates a Random Access (RA) report for an RA procedure, the RA report including at least one of the following: a second instruction indicating that the RA procedure is associated with a Small Data Transmission (SDT); a third instruction indicating that the RA procedure was successful; a fourth instruction indicating that the RA procedure failed; a fifth instruction indicating that the RA procedure is triggered during a subsequent transmission of the SDT; or a sixth instruction indicating that the RA procedure is triggered during the first transmission of the SDT.

[0139] In block 820, terminal device 110 sends an RA report to network device 120.

[0140] In some exemplary embodiments, RA resources are segmented according to different functions or combinations of functions, and if an RA procedure is triggered during the initial transmission of the SDT, the RA report further displays RA segmentation information associated with the RA procedure.

[0141] In some exemplary embodiments, the RA partitioning information indicates at least one of the following: a function or combination of functions that triggers an RA procedure, or a function or combination of functions that corresponds to an RA resource used by the RA procedure.

[0142] In some exemplary embodiments, sending an RA report includes generating an RA report upon completion of either an SDT or an RA procedure.

[0143] Figure 9 shows a flowchart of a communication method 900 implemented in a network device 120 according to several embodiments of the present disclosure. For convenience of explanation, the method 900 will be described in terms of the network device 120 of Figures 1A and 1B.

[0144] In block 910, the network device 120 receives a Random Access (RA) report for an RA procedure from the terminal device 110, the RA report being associated with a Small Data Transmission (SDT) and including at least one of the following: a second instruction indicating that the RA procedure is associated with an SDT; a third instruction indicating that the RA procedure was successful; a fourth instruction indicating that the RA procedure failed; a fifth instruction indicating that the RA procedure will be triggered during a subsequent transmission of the SDT; or a sixth instruction indicating that the RA procedure will be triggered during the first transmission of the SDT.

[0145] In some exemplary embodiments, RA resources are segmented according to different functions or combinations of functions, and if an RA procedure is triggered during the initial transmission of the SDT, the RA report further displays RA segmentation information associated with the RA procedure.

[0146] In some exemplary embodiments, the RA partitioning information indicates at least one of the following: a function or combination of functions that triggers an RA procedure, or a function or combination of functions that corresponds to an RA resource used by the RA procedure.

[0147] Figure 10 shows a flowchart of a communication method 1000 implemented in a terminal device 110 according to several embodiments of the present disclosure. For convenience of explanation, the method 1000 will be described in terms of the terminal device 110 in Figures 1A and 1B.

[0148] In block 1010, terminal device 110 receives a normal PSCell change / addition report (SPR) configuration from network device 120.

[0149] In block 1020, upon successful completion of the PSCell modification or addition procedure, the terminal device 110 stores SPR information according to the SPR configuration.

[0150] In block 1030, the terminal device 110 releases the SPR configuration or discards the SPR information when it detects at least one of the following: the release of a secondary cell group (SCG), the completion of a handover procedure, the initiation of a radio resource control (RRC) connection re-establishment procedure, the initiation of an RRC connection restart procedure, or the successful completion of a PSCell modification or addition procedure.

[0151] In some exemplary embodiments, releasing the SPR configuration upon detecting the release of the SCG or the successful completion of a modification or addition procedure to the PSCell includes releasing the SPR configuration received from the source or target secondary node (SN).

[0152] In some exemplary embodiments, the network device 120 is one of the following: a master node (MN), a source secondary node (SN), or a target SN. <Examples of devices and equipment>

[0153] Figure 11 is a simplified block diagram of an apparatus 1100 suitable for carrying out embodiments of the present disclosure. Apparatus 1100 can be considered a further exemplary embodiment of either of the apparatuses shown in Figures 1A and 1B. Thus, apparatus 1100 may be implemented in or as part of a terminal device 110 or a network device 120.

[0154] As shown in the figure, the device 1100 includes a processor 1110, a memory 1120 coupled to the processor 1110, a suitable transmitter (TX) / receiver (RX) 1140 coupled to the processor 1110, and a communication interface coupled to the TX / RX 1140. The memory 1110 stores at least a portion of the program 1130. The TX / RX 1140 is for bidirectional communication. The TX / RX 1140 has at least one antenna to facilitate communication, although in practice the access node referred to in this application may have multiple antennas. The communication interface may represent any interface necessary for communication with other network elements, such as the X2 / Xn interface for bidirectional communication between eNBs / gNBs, the S1 / NG interface for communication between Mobility Management Entities (MMEs) / Access and Mobility Management Functions (AMFs) / SGWs / UPEs and eNBs / gNBs, the Un interface for communication between eNBs / gNBs and relay nodes (RNs), or the Uu interface for communication between eNBs / gNBs and terminal devices.

[0155] The program 1130 is assumed to include program instructions, and when the program is executed by the associated processor 1110, it enables the device 1100 to operate according to embodiments of the present disclosure, as described herein with reference to Figures 1 to 10. Embodiments of the present disclosure may be implemented by computer software executable by the processor 1110 of the device 1100, by hardware, or by a combination of software and hardware. The processor 1110 may be configured to implement various embodiments of the present disclosure. Furthermore, a combination of the processor 1110 and memory 1120 may form processing means 1150 adapted to implement various embodiments of the present disclosure.

[0156] Memory 1120 may be of any type suitable for a local technology network and may be implemented using any suitable data storage technology, including but not limited to non-temporary computer-readable storage media, semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. Although only one memory 1120 is shown in device 1100, device 1100 may have multiple physically different memory modules. Processor 1110 may be of any type suitable for a local technology network and may include, but not limited to, one or more of the following: general-purpose computers, dedicated computers, microprocessors, digital signal processors (DSPs), and processors based on multicore processor architectures. Device 1100 may include multiple processors, such as application-specific integrated circuit chips that are time-dependent to a clock synchronized with the main processor.

[0157] According to embodiments of the present disclosure, a terminal device including a circuit is provided. The circuit is configured in a terminal device associated with a master cell group (MCG) of a master node (MN) and a secondary cell group (SCG) of a secondary node (SN) to detect an MCG failure, to initiate an MCG recovery procedure via the SCG in response to the detection of an MCG failure, and to store a first configuration for a radio link failure (RLF) report in response to the detection of the SCG being unavailable during the MCG recovery procedure, wherein the first configuration includes at least one identifier of at least one primary cell of at least one SCG that previously served the terminal device, the identifier of the primary cell of the SCG, a first time length from the time the last reconfiguration with synchronization was performed on the SCG to the time the SCG is detected as unavailable, a second time length from the time the MCG failure is detected to the time the SCG is detected as unavailable, or random access (RA) related information associated with the SCG. According to embodiments of the present disclosure, the circuit may be configured to perform any method performed by the terminal device as described above.

[0158] According to embodiments of the present disclosure, a terminal device including a circuit is provided. The circuit is configured to detect an MCG failure in a terminal device associated with a master cell group (MCG) of a master node (MN) and a secondary cell group (SCG) of a secondary node (SN), to initiate an MCG recovery procedure in response to the detection of an MCG failure, and to transmit second information including at least one identifier of at least one primary cell (PCell) of each of the at least one MCG that previously served the terminal device, the PCell identifier of the MCG, a third time length from the time the last handover procedure was performed to the time the MCG failure was detected, or random access (RA) related information associated with the MCG. According to embodiments of the present disclosure, the circuit may be configured to perform any method performed by the terminal device as described above.

[0159] According to embodiments of the present disclosure, a network device including a circuit is provided. The circuit is configured to receive second information from terminal devices associated with a master cell group (MCG) of a master node (MN) and a secondary cell group (SCG) of a secondary node (SN), which includes at least one identifier of at least one primary cell (PCell) of at least one MCG that previously served the terminal devices, an identifier of the PCell of the MCG, a third time period from the time the last handover procedure is performed to the time an MCG failure is detected, or random access (RA) related information associated with the MCG. According to embodiments of the present disclosure, the circuit may be configured to perform any method performed by the network device as described above.

[0160] According to embodiments of the present disclosure, a terminal device including a circuit is provided. The circuit is configured to generate and transmit an RA report to a network device, which is associated with a Small Data Transmission (SDT) and includes at least one of a second instruction indicating that the RA procedure is associated with an SDT, a third instruction indicating that the RA procedure was successful, a fourth instruction indicating that the RA procedure failed, a fifth instruction indicating that the RA procedure is triggered during a subsequent transmission of the SDT, or a sixth instruction indicating that the RA procedure is triggered during the first transmission of the SDT. According to embodiments of the present disclosure, the circuit may be configured to perform any method performed by the terminal device as described above.

[0161] According to embodiments of the present disclosure, a network device including a circuit is provided. The circuit is configured to receive a Random Access (RA) report of an RA procedure from a terminal device, the RA report including at least one of the following: a second instruction indicating that the RA procedure is associated with a Small Data Transmission (SDT), a third instruction indicating that the RA procedure was successful, a fourth instruction indicating that the RA procedure failed, a fifth instruction indicating that the RA procedure will be triggered during a subsequent transmission of the SDT, or a sixth instruction indicating that the RA procedure will be triggered during the initial transmission of the SDT. According to embodiments of the present disclosure, the circuit may be configured to perform any method performed by the network device as described above.

[0162] According to embodiments of the present disclosure, a terminal device including a circuit is provided. The circuit receives a normal PSCell Change / Addition Report (SPR) configuration from a network device, stores SPR information according to the SPR configuration in accordance with the successful completion of a PSCell change or addition procedure, and is configured to release the SPR configuration or discard the SPR information when it detects at least one of the following: release of a secondary cell group (SCG), completion of a handover procedure, commencement of a Radio Resource Control (RRC) connection re-establishment procedure, commencement of an RRC connection re-resume procedure, or successful completion of a PSCell change or addition procedure. According to embodiments of the present disclosure, the circuit may be configured to perform any method performed by the terminal device as described above.

[0163] As used herein, the term “circuit” may refer to a hardware circuit and / or a combination of a hardware circuit and software. For example, a circuit may be a combination of analog and / or digital hardware circuitry and software / firmware. As a further example, a circuit may be any part of a software-equipped hardware processor, such as a digital signal processor, software, and memory, which work together to enable a device, such as a terminal or network device, to perform various functions. In yet another example, a circuit may be a hardware circuit and / or processor, such as a microprocessor or a part of a microprocessor, which requires software / firmware for operation but may not have software when not needed for operation. As used herein, the term “circuit” also encompasses implementations of hardware circuits or processors alone, or implementations of parts of hardware circuits or processors, as well as implementations of software and / or firmware associated with them.

[0164] In summary, embodiments of this disclosure provide the following aspects:

[0165] In one embodiment, a terminal device is proposed, which includes a processor configured to cause the terminal device to detect a failure in a master cell group (MCG) of a master node (MN) and a secondary cell group (SCG) of a secondary node (SN), to initiate an MCG recovery procedure via the SCG in response to the detection of an MCG failure, and to store a first configuration for a radio link failure (RLF) report in response to the detection of an SCG unavailable during the MCG recovery procedure, wherein the first configuration includes at least one identifier of at least one primary cell of at least one SCG that previously serviced the terminal device, an identifier of the primary cell of the SCG, a first time length from the time the last reconfiguration with synchronization was performed on the SCG to the time the SCG is detected as unavailable, a second time length from the time the MCG failure is detected to the time the SCG is detected as unavailable, or random access (RA) related information associated with the SCG.

[0166] In some embodiments, detecting that the SCG is unavailable includes at least receiving a first instruction from the master node to deactivate the SCG, or detecting a failure of the SCG.

[0167] In some embodiments, the processor is further configured to cause a terminal device to initiate a procedure to re-establish a connection with a secondary node in response to the receipt of a first instruction.

[0168] In one embodiment, a terminal device is proposed, which includes a processor configured to cause the terminal device to detect a failure in a master cell group (MCG) of a master node (MN) and a secondary cell group (SCG) of a secondary node (SN), to initiate an MCG recovery procedure in response to the detection of an MCG failure, and to transmit second information including at least one identifier of at least one primary cell (PCell) of at least one MCG that previously provided service to the terminal device, the PCell identifier of the MCG, a third time period from the time the last handover procedure was performed to the time the MCG failure was detected, or random access (RA) related information associated with the MCG.

[0169] In some embodiments, transmitting RA-related information associated with the MCG includes transmitting RA-related information associated with the MCG when the MCG failure is caused by an RA failure.

[0170] In some embodiments, transmitting the second information includes transmitting the second information via one of the following: MCG failure information used by a terminal device to initiate an MCG recovery procedure, or a failure report transmitted in response to the receipt of a request for the second information.

[0171] In one embodiment, a network device is proposed, which includes a processor configured to cause the network device to receive from terminal devices associated with a master cell group (MCG) of a master node (MN) and a secondary cell group (SCG) of a secondary node (SN) the following second pieces of information: at least one identifier of at least one primary cell (PCell) of at least one MCG that previously provided service to the terminal devices, the identifier of the PCell of the MCG, a third time period from the time the last handover procedure is performed until the time an MCG failure is detected, or random access (RA) related information associated with the MCG.

[0172] In some embodiments, RA-related information indicates RA failure information.

[0173] In some embodiments, the network device is an MN, and receiving the second information includes receiving MCG failure information containing the second information from a terminal device, the MCG failure information being used by the terminal device to initiate an MCG recovery procedure.

[0174] In some embodiments, the processor is further configured to send a request for a second piece of information to a terminal device via a network device.

[0175] In one embodiment, a terminal device is proposed, which includes a processor configured to cause the terminal device to generate an RA report, which is associated with a Small Data Transmission (SDT), and to transmit the RA report to a network device, the RA report comprising at least one of the following: a second instruction indicating that the RA procedure is associated with an SDT; a third instruction indicating that the RA procedure was successful; a fourth instruction indicating that the RA procedure failed; a fifth instruction indicating that the RA procedure is triggered during a subsequent transmission of the SDT; or a sixth instruction indicating that the RA procedure is triggered during the first transmission of the SDT.

[0176] In some embodiments, RA resources are partitioned according to different functions or combinations of functions, and if an RA procedure is triggered during the initial transmission of the SDT, the RA report further shows the RA partitioning information associated with the RA procedure.

[0177] In some embodiments, the RA partitioning information indicates at least one of the following: a function or combination of functions that triggers an RA procedure, or a function or combination of functions that corresponds to an RA resource used by the RA procedure.

[0178] In some embodiments, sending an RA report includes generating an RA report in response to either the completion of an SDT or the completion of an RA procedure.

[0179] In one embodiment, a network device is proposed, the network device including a processor configured to cause the network device to receive a random access (RA) report of an RA procedure from a terminal device, the RA report being associated with a small data transmission (SDT) and including at least one of a second instruction indicating that the RA procedure is associated with an SDT, a third instruction indicating that the RA procedure was successful, a fourth instruction indicating that the RA procedure failed, a fifth instruction indicating that the RA procedure is triggered during a subsequent transmission of the SDT, or a sixth instruction indicating that the RA procedure is triggered during the first transmission of the SDT.

[0180] In some embodiments, RA resources are partitioned according to different functions or combinations of functions, and if an RA procedure is triggered during the initial transmission of the SDT, the RA report further shows the RA partitioning information associated with the RA procedure.

[0181] In some embodiments, the RA partitioning information indicates at least one of the following: a function or combination of functions that triggers an RA procedure, or a function or combination of functions that corresponds to an RA resource used by the RA procedure.

[0182] In one embodiment, a terminal device is proposed, which includes a processor configured to receive a normal PSCell change / addition report (SPR) configuration from a network device, store SPR information according to the SPR configuration in accordance with the successful completion of a PSCell change or addition procedure, and to release the SPR configuration or discard the SPR information when it detects at least one of the following: release of a secondary cell group (SCG), completion of a handover procedure, commencement of a radio resource control (RRC) connection re-establishment procedure, commencement of an RRC connection re-resume procedure, or successful completion of a PSCell change or addition procedure.

[0183] In some embodiments, releasing the SPR configuration upon detection of the release of the SCG or the successful completion of a modification or addition procedure to the PSCell includes releasing the SPR configuration received from the source or target secondary node (SN).

[0184] In some embodiments, the network device is one of the following: a master node (MN), a source secondary node (SN), or a target SN.

[0185] In one embodiment, the terminal device includes at least one processor and at least one memory coupled to the at least one processor for storing instructions, wherein when an instruction is executed by the at least one processor, the device causes the device to perform the method performed by the terminal device described above.

[0186] In one embodiment, the network device includes at least one processor and at least one memory coupled to the at least one processor for storing instructions, wherein when an instruction is executed by the at least one processor, the device causes the device to perform the method performed by the network device described above.

[0187] In one embodiment, a computer-readable medium stores instructions, and when these instructions are executed on at least one processor, they cause at least one processor to perform the method carried out by the terminal device described above.

[0188] In one embodiment, a computer-readable medium stores instructions, and when these instructions are executed on at least one processor, they cause at least one processor to perform the method carried out by the network device described above.

[0189] In one embodiment, a computer program including instructions, which, when executed on at least one processor, causes at least one processor to perform the method carried out by the terminal device described above.

[0190] In one embodiment, a computer program including instructions, which, when executed on at least one processor, causes at least one processor to perform the method carried out by the network device described above.

[0191] In general, various embodiments of the present disclosure may be implemented in hardware or dedicated circuitry, software, logic, or any combination thereof. Some embodiments may be implemented in hardware, while others may be implemented in firmware or software executed by a controller, microprocessor, or other computing device. Although various embodiments of the present disclosure are illustrated and described using block diagrams, flowcharts, or some other graphical representations, it will be understood that any block, apparatus, system, technique, or method described herein may be implemented, in non-limiting examples, in hardware, software, firmware, dedicated circuitry or logic, general-purpose hardware or controller, or other computing device, or some combination thereof.

[0192] This disclosure also provides at least one computer program product tangibly stored on a non-temporary computer-readable storage medium. The computer program product includes computer-executable instructions, such as instructions contained in a program module, which are executed on a device on a target real or virtual processor, and perform the processes or methods described above with reference to Figures 1 to 11. Generally, a program module includes routines, programs, libraries, objects, classes, components, data structures, etc., that perform a specific task or implement a specific abstract data type. The functions of program modules may be combined or separated as needed in various embodiments. The machine-executable instructions for a program module may be executed in a local or distributed device. In a distributed device, the program module may reside on both local and remote storage media.

[0193] Program code for performing the methods of this disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general-purpose computer, a dedicated computer, or other programmable data processing device, and when executed by the processor or controller, they perform the functions / operations specified in the flowcharts and / or block diagrams. The program code may run entirely on a machine, partially on a machine, as a standalone software package, partially on a machine and partially on a remote machine, or entirely on a remote machine or server.

[0194] The above program code may be embodied in a machine-readable medium, which may be any tangible medium that contains or can store a program used by an instruction execution system, apparatus, or device, or a program used in conjunction with such a system or device. The machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. The machine-readable medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination thereof. More specific examples of machine-readable storage media include electrical connections with one or more wires, portable computer diskettes, hard disks, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM, or flash memory), optical fibers, compact disc read-only memory (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination thereof.

[0195] Furthermore, although the operations are presented in a specific order, it should not be understood that such operations must be performed in the specific order shown, sequentially, or all shown operations must be performed in order to obtain the desired results. In certain circumstances, multitasking and parallel processing may be advantageous. Similarly, the above description includes some specific implementation details, but these should not be interpreted as limiting the scope of this disclosure, but rather as descriptions of features that may be specific to a particular embodiment. Certain features described in the context of individual embodiments may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may be implemented individually or in any suitable combination of sub-features in multiple embodiments.

[0196] While this disclosure is described in language specific to structural features and / or methodological actions, it should be understood that the disclosure as defined in the appended claims is not necessarily limited to the specific features or actions described above. Rather, the specific features and actions described above are disclosed as exemplary forms of implementing the claims.

Claims

1. A terminal device, The aforementioned terminal device, In the terminal device associated with the Master Cell Group (MCG) of the Master Node (MN) and the Secondary Cell Group (SCG) of the Secondary Node (SN), a failure in the MCG is detected. In response to the detection of the malfunction in the MCG, the MCG recovery procedure is initiated via the SCG. During the MCG recovery procedure, in response to the detection that the SCG is unavailable, a first configuration for a Radio Link Failure (RLF) report is stored, and the first information is At least one identifier of at least one primary cell of at least one SCG that previously provided services to the terminal device, The identifier of the primary cell of the aforementioned SCG, A first time length from the time when the last reconfiguration with synchronization is performed in the SCG until the time when it is detected that the SCG is unavailable, The second time period from the time when a malfunction of the MCG is detected to the time when it is detected that the SCG is unavailable, or Random Access (RA) related information associated with the aforementioned SCG, Including at least one of the following: Including a processor configured as follows: Terminal device.

2. Detecting that the SCG is unavailable means at least, Receiving a first instruction from the MN to deactivate the SCG, or To detect a malfunction in the aforementioned SCG, including, The terminal device according to claim 1.

3. The processor further provides the terminal device with: In response to receiving the first instruction, the system is configured to initiate a procedure to re-establish the connection with the SN. The terminal device according to claim 2.

4. A terminal device, The aforementioned terminal device, In the terminal device associated with the master cell group (MCG) of the master node (MN) and the secondary cell group (SCG) of the secondary node (SN), a failure in the MCG is detected. In response to the detection of the malfunction in the MCG, the MCG recovery procedure is initiated via the SCG, and At least one identifier of at least one primary cell (PCell) of at least one MCG that previously provided services to the terminal device, The PCell identifier of the aforementioned MCG, A third time period from the time the last handover procedure is performed until the time the failure of the MCG is detected, or Random access (RA) related information associated with the aforementioned MCG, To transmit a second piece of information that includes at least one of the following: Including a processor configured as follows: Terminal device.

5. Transmitting the RA-related information associated with the MCG is: The transmission of RA-related information associated with the MCG when the MCG failure is caused by a RA failure, The terminal device according to claim 4.

6. Sending the information mentioned in the second paragraph means The second piece of information mentioned above, MCG failure information used by the terminal device to initiate the MCG recovery procedure, or A fault report transmitted in response to the receipt of the second information request, Including sending via one of the following, The terminal device according to claim 4.

7. A terminal device, The aforementioned terminal device, A Random Access (RA) report for an RA procedure, associated with Small Data Transmission (SDT), A second instruction indicating that the RA procedure is associated with the SDT, A third instruction indicating that the RA procedure was successful, A fourth instruction indicating that the RA procedure has failed, A fifth instruction indicating that the RA procedure is triggered during a subsequent transmission of the SDT, or A sixth indication that the RA procedure is triggered during the initial transmission of the SDT, Generate an RA report that includes at least one of the following, and The RA report is sent to the network device. Including a processor configured as follows: Terminal device.

8. RA resources are divided according to different functions or combinations of functions, If the RA procedure is triggered during the initial transmission of the SDT, the RA report further indicates the RA segmentation information associated with the RA procedure. The terminal device according to claim 7.

9. The aforementioned RA division information, A function or combination of functions that triggers the aforementioned RA procedure, or Functions or combinations of functions corresponding to the RA resources used by the aforementioned RA procedure, Showing at least one of the following: The terminal device according to claim 7.

10. The aforementioned RA report, Completion of the aforementioned SDT, or Completion of the aforementioned RA procedure, Generated according to one of the following: The terminal device according to claim 7.

11. A terminal device, The aforementioned terminal device, The network device receives a successful PSCell Change / Addition Report (SPR) configuration. Upon successful completion of any modification or addition procedure to PSCell, SPR information is stored according to the SPR configuration, and Release of secondary cell groups (SCGs) Completion of the handover procedure. Initiating the Radio Resource Control (RRC) connection re-establishment procedure. Initiating the RRC connection restart procedure, or Successful completion of PSCell modification or additional steps. If at least one of the above is detected, the SPR configuration is released or the SPR information is discarded. Including a processor configured as follows: Terminal device.

12. When the release of the SCG or the successful completion of the PSCell modification or addition procedure is detected, the SPR configuration is released. This includes releasing the SPR configuration received from the source or target secondary node (SN), The terminal device according to claim 11.

13. The terminal device according to claim 11, wherein the network device is one of a master node (MN), a source secondary node (SN), or a target SN.

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