Communication method, terminal device, and network device

Abstract

The present application provides a communication method, a terminal device, and a network device. The method comprises: a terminal device receives first conditional configuration information from a source node; and, on the basis of the first conditional configuration information, the terminal device executes an L1 / L2-triggered mobility (LTM) process.

Description

Communication method, terminal equipment and network equipment Technical Field

[0001] The present application relates to the field of communication technology, and more specifically, to a communication method, terminal equipment and network equipment. Background Art

[0002] Layer 1 / Layer 2-triggered mobility (LTM) technology can effectively shorten handover latency. Further optimizing the LTM process is a challenge that needs to be addressed.

[0003] Summary of the Invention

[0004] The present application provides a communication method, terminal equipment, and network equipment. Several aspects of the present application are introduced below.

[0005] In a first aspect, a communication method is provided, comprising: a terminal device receiving first conditional configuration information from a source node; and the terminal device executing a layer 1 / layer 2 triggered mobility LTM process based on the first conditional configuration information.

[0006] According to a second aspect, a communication method is provided, comprising: a source node sends first conditional configuration information to a terminal device, wherein the first conditional configuration information is used by the terminal device to execute a layer 1 / layer 2 triggered mobility LTM process; wherein the source node is a source cell; or, the source node is a centralized unit CU or a base station to which the source cell belongs.

[0007] According to a third aspect, a communication method is provided, comprising: a first candidate node sends conditional configuration information to a source node, wherein the conditional configuration information is used by a terminal device to execute a layer 1 / layer 2 triggered mobility LTM process; wherein the first candidate node is a first candidate cell; or, the first candidate node is a centralized unit CU or a base station to which the first candidate cell belongs.

[0008] In a fourth aspect, a terminal device is provided, comprising a receiving unit for receiving first conditional configuration information from a source node; and an execution unit for executing a layer 1 / layer 2 triggered mobility LTM process based on the first conditional configuration information.

[0009] In the fifth aspect, a network device is provided, which is a source node, and the network device includes: a sending unit, used to send first conditional configuration information to a terminal device, and the first conditional configuration information is used for the terminal device to perform a layer 1 / layer 2 triggered mobility LTM process; wherein, the source node is a source cell; or, the source node is a centralized unit CU or base station to which the source cell belongs.

[0010] In the sixth aspect, a network device is provided, which is a first candidate node, and the network device includes: a sending unit for sending conditional configuration information to the source node, and the conditional configuration information is used for the terminal device to execute the layer 1 / layer 2 triggered mobility LTM process; wherein, the first candidate node is the first candidate cell; or, the first candidate node is the CU or base station to which the first candidate cell belongs.

[0011] In the seventh aspect, a terminal device is provided, comprising a processor, a memory, and a communication interface, wherein the memory is used to store one or more computer programs, and the processor is used to call the computer program in the memory so that the terminal device executes part or all of the steps in the method of the first aspect.

[0012] In an eighth aspect, a network device is provided, comprising a processor, a memory, and a communication interface, wherein the memory is used to store one or more computer programs, and the processor is used to call the computer program in the memory so that the network device executes part or all of the steps in the method of the second aspect or the third aspect.

[0013] In a ninth aspect, an embodiment of the present application provides a communication system, which includes the above-mentioned terminal and / or network device. In another possible design, the system may also include other devices that interact with the terminal or network device in the solution provided in the embodiment of the present application.

[0014] In the tenth aspect, an embodiment of the present application provides a computer-readable storage medium, which stores a computer program, and the computer program enables a terminal device to execute some or all of the steps in the method of the first aspect above.

[0015] In the eleventh aspect, an embodiment of the present application provides a computer-readable storage medium, which stores a computer program, and the computer program enables the network device to execute part or all of the steps in the method of the second or third aspect above.

[0016] In a twelfth aspect, embodiments of the present application provide a computer program product, wherein the computer program product includes a non-transitory computer-readable storage medium storing a computer program, wherein the computer program is operable to cause a terminal to perform some or all of the steps of the method of the first aspect. In some implementations, the computer program product may be a software installation package.

[0017] In a thirteenth aspect, embodiments of the present application provide a computer program product, wherein the computer program product includes a non-transitory computer-readable storage medium storing a computer program, wherein the computer program is operable to cause a network device to perform some or all of the steps of the method of the second or third aspect described above. In some implementations, the computer program product may be a software installation package.

[0018] In the thirteenth aspect, an embodiment of the present application provides a chip comprising a memory and a processor, wherein the processor can call and run a computer program from the memory to implement some or all of the steps described in the method of the first aspect, the second aspect, or the third aspect above.

[0019] In the technical solution provided by the embodiment of the present application, the terminal device receives first conditional configuration information from the source node and executes the LTM process based on the first conditional configuration information. Therefore, the terminal device can perform operations related to the LTM process when the conditions are met, reduce unnecessary operations, and thus optimize the LTM process. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] FIG1 is a wireless communication system used in an embodiment of the present application.

[0021] Figure 2 is a conditional switching flow chart.

[0022] FIG3 is a flow chart of the LTM process.

[0023] FIG4 is a schematic flowchart of a communication method provided in an embodiment of the present application.

[0024] FIG5 is a flowchart of a possible implementation of the communication method in FIG4 .

[0025] FIG6 is a flowchart of another possible implementation of the communication method in FIG4 .

[0026] FIG7 is a schematic block diagram of a terminal device provided in an embodiment of the present application.

[0027] FIG8 is a schematic block diagram of a network device provided in an embodiment of the present application.

[0028] FIG9 is a schematic block diagram of another network device provided in an embodiment of the present application.

[0029] FIG10 is a schematic structural diagram of a communication device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0030] The technical solution in this application will be described below with reference to the accompanying drawings.

[0031] Figure 1 illustrates a wireless communication system 100 used in an embodiment of the present application. The wireless communication system 100 may include a network device 110 and a terminal device 120. The network device 110 may be a device that communicates with the terminal device 120. The network device 110 may provide communication coverage for a specific geographic area and may communicate with the terminal device 120 within the coverage area.

[0032] FIG1 exemplarily shows a network device and two terminal devices. Optionally, the wireless communication system 100 may include multiple network devices and each network device may include another number of terminal devices within its coverage area, which is not limited in this embodiment of the present application.

[0033] Optionally, the wireless communication system 100 may further include other network entities such as a network controller and a mobility management entity, which is not limited in the embodiment of the present application.

[0034] It should be understood that the technical solutions of the embodiments of the present application can be applied to various communication systems, such as: fifth generation (5G) system or new radio (NR), long term evolution (LTE) system, LTE frequency division duplex (FDD) system, LTE time division duplex (TDD), etc. The technical solutions provided in this application can also be applied to future communication systems, such as the sixth generation mobile communication system, satellite communication system, etc.

[0035] The terminal device in the embodiments of the present application may also be referred to as user equipment (UE), access terminal, user unit, user station, mobile station, mobile station (MS), mobile terminal (MT), remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent or user device. The terminal device in the embodiments of the present application may refer to a device that provides voice and / or data connectivity to a user and can be used to connect people, objects and machines, such as a handheld device with wireless connection function, a vehicle-mounted device, etc. The terminal device in the embodiments of the present application can be a mobile phone, a tablet computer, a laptop computer, a PDA, a mobile internet device (MID), a wearable device, a virtual reality (VR) device, an augmented reality (AR) device, a wireless terminal in industrial control, a wireless terminal in self-driving, a wireless terminal in remote medical surgery, a wireless terminal in a smart grid, a wireless terminal in transportation safety, a wireless terminal in a smart city, a wireless terminal in a smart home, etc. Optionally, the UE can be used to act as a base station. For example, the UE can act as a scheduling entity that provides sidelink signals between UEs in V2X or D2D, etc. For example, a cellular phone and a car communicate with each other using sidelink signals. The cellular phone and smart home devices communicate without relaying the communication signal through the base station.

[0036] The network device in the embodiments of the present application may be a device for communicating with a terminal device, and may also be referred to as an access network device or a radio access network device. For example, the network device may be a base station. The network device in the embodiments of the present application may refer to a radio access network (RAN) node (or device) that connects a terminal device to a wireless network. A base station can broadly cover various names as follows, or be replaced with the following names, such as: NodeB, evolved NodeB (eNB), next generation NodeB (gNB), relay station, transmission point (TRP), transmission point (TP), master station MeNB, secondary station SeNB, multi-standard radio (MSR) node, home base station, network controller, access node, wireless node, access point (AP), transmission node, transceiver node, baseband unit (BBU), remote radio unit (RRU), active antenna unit (AAU), remote radio head (RRH), CU, distributed unit (DU), positioning node, etc. A base station can be a macro base station, a micro base station, a relay node, a donor node or the like, or a combination thereof. A base station can also refer to a communication module, modem or chip used to be set in the aforementioned device or apparatus. The base station can also be a mobile switching center and a device that performs base station functions in device-to-device D2D, vehicle-to-everything (V2X), and machine-to-machine (M2M) communications, a network-side device in a 6G network, or a device that performs base station functions in future communication systems. The base station can support networks with the same or different access technologies. The embodiments of this application do not limit the specific technology and specific device form used by the network equipment.

[0037] Base stations can be fixed or mobile. For example, a helicopter or drone can be configured to act as a mobile base station, and one or more cells can move based on the location of the mobile base station. In other examples, a helicopter or drone can be configured to act as a device that communicates with another base station.

[0038] In some deployments, the network device in the embodiments of the present application may refer to a CU or a DU, or the network device may include a CU and a DU. The gNB may also include an AAU.

[0039] The network equipment and terminal devices can be deployed on land, including indoors or outdoors, handheld or vehicle-mounted; they can also be deployed on the water; they can also be deployed in the air on aircraft, balloons, or satellites. The embodiments of this application do not limit the scenarios in which the network equipment and terminal devices are located.

[0040] It should be understood that all or part of the functions of the communication device in this application can also be implemented through software functions running on hardware, or through virtualization functions instantiated on a platform (such as a cloud platform).

[0041] Cell switching

[0042] Cell handover (HO) aims to improve the continuity of services provided by the communication system to terminal devices. In a wireless communication system, when a terminal device moves from one cell (also known as the "serving cell," "current serving cell," or "source cell") to another, in order to maintain communication, the terminal device needs to handover to another cell (also known as the "target cell" or "target serving cell"). The cell can be a primary cell (PCell) or a primary secondary cell (PSCell). Generally, cell handover can be divided into two types: traditional handover mechanism and conditional handover mechanism.

[0043] In a traditional handover mechanism, to improve the continuity of services provided by the communication system to connected terminal devices, the network device will send a handover command to the terminal device at an appropriate time (for example, when the signal measurement result of the terminal device in the serving cell falls below a threshold) to instruct the terminal device to perform a cell handover. In some implementations, the handover command may be a radio resource control (RRC) reconfiguration message containing synchronization reconfiguration information.

[0044] For the conditional handover (CHO) mechanism, the network device can configure the configuration of one or more candidate cells and the conditional handover events associated with one or more candidate cells to the terminal device. The conditional handover event can also be called the conditional handover trigger condition. Accordingly, the terminal device can determine whether the conditional handover event is met based on the signal measurement results of the candidate cell. If the terminal device determines that a candidate cell meets the conditional handover event, the terminal device can initiate random access to the candidate cell.

[0045] The following describes the conditional switching process in conjunction with FIG2 .

[0046] In step S202, the terminal device sends a measurement report to the serving cell.

[0047] In step S204, the serving cell determines a handover strategy based on the measurement report. If the serving cell determines that the terminal device needs to perform a cell handover, the serving cell may send a handover request to the candidate cell.

[0048] In step S206, the serving cell sends a handover request to the candidate cell.

[0049] In step S208, if the candidate cell accepts the handover request, RRC configuration may be established.

[0050] In step S210, the candidate cell sends a handover confirmation message to the serving cell. The handover confirmation message may include the RRC configuration of the candidate cell.

[0051] In step S212, after receiving the handover confirmation message, the serving cell may send a conditional handover command to the terminal device.

[0052] In step S214, the terminal device measures the candidate cell. If the candidate cell meets the switching condition, the terminal device may trigger conditional switching.

[0053] In step S216, the terminal device initiates random access to the candidate cell to synchronize with the candidate cell.

[0054] In step S218, the terminal device sends a handover confirmation message to the candidate cell.

[0055] In step S220, the candidate cell sends a handover completion message to the serving cell.

[0056] In some implementations, the conditional handover command includes configuration information of at least one candidate cell and / or handover condition configuration.

[0057] In some embodiments, if the network device has configured multiple candidate cells for a terminal device, and the terminal device attempts to access one of the candidate cells, if random access fails due to channel deterioration, load balancing, or other reasons, the terminal device may reselect a candidate cell to attempt access. If the terminal device fails to access the candidate cell again, the conditional handover process fails, and the terminal device needs to reestablish the connection.

[0058] The current conditional handover mechanism is triggered by L3 measurements and completed through RRC signaling. L3-based handover requires reconfiguration of the RRC layer or PDCP layer, and reset of the MAC layer and / or physical layer, which increases the complexity of the handover process and increases the handover delay. In order to further shorten the handover delay and ensure service continuity, the Third Generation Partnership Project (3GPP) has developed a rdGeneration Partnership Project (3GPP) R18 supports the Layer 1 / Layer 2 triggered mobility (L1 / L2-triggered mobility, LTM) mechanism.

[0059] LTM Process

[0060] LTM uses L1 / L2 signaling to change the serving cell of a terminal device while maintaining the high-level configuration unchanged, which helps reduce latency, lower overhead, and shorten interruption time.

[0061] During the LTM execution phase, the terminal device can periodically report L1 measurement results. The network device can make LTM decisions based on these measurements and send handover commands to the terminal device. The terminal device can then leave the current serving cell and attempt to access the target LTM cell. During the LTM decision process, the terminal device retains the configuration information of the LTM candidate cell after the handover is complete to facilitate subsequent handovers.

[0062] In some embodiments, the network device may send a handover command to the terminal device in the form of a MAC CE. In other words, the handover command may be carried in the MAC CE.

[0063] The LTM process is described in detail below with reference to Figure 3. The LTM process can be roughly divided into four phases: LTM preparation (e.g., steps S302 through S308), pre-synchronization (e.g., step S310), LTM execution (e.g., steps S312 through S318), and LTM completion (e.g., step S320). Each step is described in detail below.

[0064] 3 , in step S302 , the terminal device may send a measurement report to the network device. The terminal device in the embodiment of the present application may be a terminal device in an RRC connected state.

[0065] In some embodiments, the measurement report may be obtained based on L3 measurements.

[0066] In step S304, the network device may determine whether to initiate an LTM process based on the measurement report. If the network device determines to initiate an LTM process, the network device may trigger the candidate cell to perform handover preparation.

[0067] In step S306, the network device sends an RRC reconfiguration message (i.e., an RRC reconfiguration message) to the terminal device. The RRC reconfiguration message may include configuration information for candidate cells. The number of candidate cells may be one or more. After receiving the RRC reconfiguration message, the terminal device may store the configuration information for the candidate cells in the RRC reconfiguration message.

[0068] In step S308, the terminal device sends an RRC reconfiguration completion message (ie, an RRC reconfiguration complete message) to the network device.

[0069] In step S310, the terminal device performs uplink synchronization and / or downlink synchronization with the candidate cell. The terminal device may perform uplink synchronization and / or downlink synchronization with the candidate cell in advance to reduce the interruption delay of the handover process.

[0070] In step S312, the terminal device sends a measurement report to the network device. The measurement report may be obtained for L1 measurement and may include measurement results for one or more candidate cells.

[0071] In step S314, the network device makes an LTM decision. If the network device determines that the terminal device can perform a cell handover, the process proceeds to step S316. In some embodiments, the network device may determine a target cell based on the measurement results reported by the terminal device and instruct the terminal device to switch to the target cell. In some embodiments, the network device may instruct the terminal device to switch to the target cell via a media access control element (MAC CE).

[0072] In step S316, the network device sends a cell switch command to the terminal device. The cell switch command may be carried in a MAC CE and is used to instruct the terminal device to switch to a target cell.

[0073] In step S318, the terminal device leaves the serving cell and initiates a random access procedure to the target cell. In some embodiments, the terminal device may use the configuration information of the target cell to initiate the random access procedure to the target cell. If the terminal device does not have a valid timing advance (TA) or terminal control interface state identity (TCI state ID) for the target cell, the terminal device may initiate a random access procedure to the target cell after receiving a cell handover command sent by the network device.

[0074] In step S320, the terminal device and the network device complete the LTM switching process.

[0075] As described above, LTM can effectively reduce handover latency. With the advancement of communication technology, LTM needs to be applied to more scenarios. Therefore, further optimizing the LTM process is a challenge that needs to be addressed.

[0076] For example, currently, the scenarios supported by LTM in R18 are mainly LTM within the CU (intra-CU LTM). Compared with R18's R18 intra-CU LTM, the LTM proposed in R19 has expanded the supported scenarios, and it also considers LTM between CUs (inter-CU LTM) and conditional LTM (CLTM). Therefore, for the scenarios supported by R19's LTM, how to further reduce the amount of data transmitted over the air interface and shorten the switching time has become an urgent problem to be solved.

[0077] Taking into account that R19 proposes that LTM can additionally support L1 measurement reporting triggered by events (or conditions), the embodiment of the present application proposes that R19 LTM can also perform LTM or related operations in the LTM process based on events, thereby avoiding unnecessary data transmission (unnecessary data transmission may, for example, include unnecessary measurement reporting and cell switching), thereby further reducing the amount of data transmitted over the air interface and shortening the switching time.

[0078] In view of this, an embodiment of the present application proposes a communication method in which a terminal device can receive first conditional configuration information from a source node. The first conditional configuration information is conditional configuration information used in executing the LTM process (or event configuration information, which can be used to configure conditions or events). Based on the first conditional configuration information, the terminal device can perform operations related to the LTM process when the conditions are met, reducing unnecessary operations, thereby optimizing the LTM process (such as reducing the amount of data transmitted over the air interface and shortening the switching time).

[0079] The communication method provided in the embodiment of the present application is described in detail below with reference to FIG4 .

[0080] 4 , in step S410 , the source node sends first condition configuration information to the terminal device.

[0081] In step S420 , the terminal device performs a layer 1 / layer 2 triggered mobility LTM process based on the first condition configuration information.

[0082] The first conditional configuration information is conditional configuration information used during the LTM process. In other words, the first conditional configuration information can be used to indicate one or more conditions related to the LTM process. In other words, the first conditional configuration information can be used during the LTM process. In other words, the first conditional configuration information is associated with LTM. In some embodiments, the first conditional configuration information can be carried in an RRC reconfiguration message. Of course, in other embodiments, the first conditional configuration information can also be carried in other types of messages.

[0083] The LTM process mentioned in the embodiment of the present application can be a continuous LTM process. In the continuous LTM process, the first condition configuration information can be the condition configuration information used in the execution of the initial LTM process, or the condition configuration information used in the execution of the subsequent LTM process after the initial LTM is completed.

[0084] The embodiments of the present application do not specifically limit the type of LTM process. In some embodiments, the LTM process may include one of the following: an intra-CU LTM process, an inter-CU LTM process, a master cell group (MCG) LTM process, or a secondary cell group (SCG) LTM process. In other embodiments, the LTM process may also be the CLTM process described above.

[0085] The source node may refer to the current node providing network services to the terminal device. In some embodiments, the source node may refer to the source cell. In other embodiments, the source node may refer to the CU or base station to which the source cell belongs. In this case, the source node may also be referred to as the source CU or source base station.

[0086] In some embodiments, the source node may refer to a node from which the terminal device first receives the LTM configuration.

[0087] In other embodiments, the source node may refer to the current service node of the terminal device during a subsequent LTM process. The current service node of the terminal device may refer to the service node the terminal device is currently located at before each LTM execution. Alternatively, the current service node of the terminal device may refer to the service node the terminal device is currently located at after each LTM execution.

[0088] In some embodiments, the terminal device executes the mobility LTM process triggered by layer 1 / layer 2 based on the first condition configuration information, including that the terminal device can execute one or more operations in the LTM process based on the first condition configuration information. For example, the operations in the LTM process may include one or more of the following operations: executing the CLTM process; reporting the measurement results of the candidate cell to the source node; performing uplink synchronization and / or downlink synchronization with the candidate cell in advance; performing data forwarding; and determining the SCG processing method. That is, the terminal device executes the mobility LTM process triggered by layer 1 / layer 2 based on the first condition configuration information, including that the terminal device performs one or more of the following operations based on the first condition configuration information: executing CLTM; reporting the measurement results of the candidate cell to the source node; performing uplink synchronization and / or downlink synchronization with the candidate cell in advance; performing data forwarding; and determining the SCG processing method. Reporting the measurement results of the candidate cell to the source node may, for example, be reporting the L1 measurement results of the candidate cell to the source node.

[0089] It should be understood that the content of the first conditional configuration information can be set according to the type of operation triggered, indicated, or configured by the first conditional configuration information, and this embodiment of the present application does not specifically limit this. The following examples illustrate the content of the first conditional configuration information in conjunction with the type of operation triggered, indicated, or configured by the first conditional configuration information.

[0090] As an example, when the LTM process is a CLTM process, the operations performed by the terminal device triggered, indicated, or configured by the first conditional configuration information may include one or more of the following operations: executing CLTM; reporting the measurement results of the candidate cell to the source node; performing uplink synchronization and / or downlink synchronization with the candidate cell in advance; performing data forwarding; and determining the SCG processing method. Accordingly, the first conditional configuration information may include one or more of the following information: conditional configuration information for triggering, indicating, or configuring CLTM; conditional configuration information for triggering, indicating, or configuring the terminal device to report the measurement results of the LTM candidate cell; conditional configuration information for triggering, indicating, or configuring the process of obtaining uplink synchronization and / or downlink synchronization with the candidate cell in advance; conditional configuration information for triggering, indicating, or configuring the execution of data forwarding; and conditional configuration information for triggering, indicating, or configuring the determination of the SCG processing method.

[0091] As another example, when the LTM process is an inter-CU LTM process, the operations performed by the terminal device triggered, indicated, or configured by the first conditional configuration information may include one or more of the following operations: reporting the measurement results of the candidate cell to the source node; performing uplink synchronization and / or downlink synchronization with the candidate cell in advance; and performing data forwarding. Accordingly, the first conditional configuration information may include one or more of the following information: conditional configuration information for triggering, indicating, or configuring the terminal device to report the measurement results of the LTM candidate cell; conditional configuration information for triggering, indicating, or configuring the process of obtaining uplink synchronization and / or downlink synchronization with the candidate cell in advance; and conditional configuration information for triggering, indicating, or configuring the execution of data forwarding.

[0092] The embodiments of the present application do not specifically limit the configuration granularity of the first conditional configuration information. For example, the first conditional configuration information may be common configuration information applicable to all candidate cells; or the first conditional configuration information may include conditional configuration information corresponding to at least one candidate cell; or the first conditional configuration information may include conditional configuration information corresponding to at least one group of candidate cells.

[0093] In some embodiments, a group of candidate cells belongs to the same DU.

[0094] In some further embodiments, a group of candidate cells belongs to the same CU.

[0095] The embodiment of the present application does not specifically limit the configuration node of the first condition configuration information.

[0096] For example, the first conditional configuration information is generated (or configured) by the source node. For example, the source node configures or generates the first conditional configuration information after receiving the LTM configuration. In this case, the first conditional configuration information can be common configuration information, applicable to all candidate cells.

[0097] For another example, the first condition configuration information is generated (or configured) by the node to which the service cell of the terminal device belongs. During the LTM process, if the terminal device has not yet switched or successfully switched to the target cell, the service cell of the terminal device is still the source cell, and accordingly, the node to which the service cell of the terminal device belongs can refer to the source node; if the terminal device has switched or successfully switched to the target cell, the service cell of the terminal device can refer to the target cell, and accordingly, the node to which the service cell of the terminal device belongs can refer to the node to which the target cell belongs. Of course, after the terminal device switches or successfully switches to the target cell, the target cell can also be understood as the source cell of the subsequent LTM process.

[0098] The embodiment of the present application generates and sends the first conditional configuration information through the source node or the node to which the service cell of the terminal device belongs. It can reduce unnecessary operations in the process of instructing the terminal device to perform LTM, and can also make the configuration method of the first conditional configuration information easier to implement and improve the configuration efficiency of the first conditional configuration information.

[0099] For another example, the first conditional configuration information is generated (or configured) by at least one candidate node or at least one candidate cell. For example, assuming that the candidate nodes participating in the LTM process include a first candidate node (which can be any candidate node participating in the LTM process), the first candidate node generates its own conditional configuration information. Then, the first candidate node can send the conditional configuration information to the terminal device through the source node, so that the terminal device performs the LTM process based on the conditional configuration information. The first candidate node mentioned here is the first candidate cell; alternatively, the first candidate node is the CU or base station to which the first candidate cell belongs.

[0100] The embodiment of the present application generates at least one candidate node or at least one candidate cell, respectively, and can achieve personalized configuration while reducing unnecessary operations in the process of instructing the terminal device to perform LTM.

[0101] The first conditional configuration information can be sent to the terminal device together with other configuration information (eg, at least one candidate cell configuration or LTM configuration) via one message. Alternatively, the first conditional configuration information can be sent to the terminal device together with other configuration information via multiple messages.

[0102] In some embodiments, the source node sends a first request to the first candidate node, where the first request is used to request the first candidate node to provide configuration information of the first candidate cell. The first candidate node is the first candidate cell (which can be any candidate cell in the LTM process); or the first candidate node is the CU or base station to which the first candidate cell belongs.

[0103] In some embodiments, the first request may be triggered or instructed by the source node based on a measurement result of the terminal device. The measurement result of the terminal device may be determined based on a measurement report of the terminal device.

[0104] In some embodiments, the first request includes third indication information, where the third indication information is used to indicate the type of the LTM process: LTM, CLTM, inter-CU LTM, or intra-CU LTM. For example, in a CLTM scenario, the first request includes third indication information indicating that the current LTM process is CLTM. In an inter-CU LTM scenario, the first request includes third indication information indicating that the current LTM process is inter-CU LTM or LTM.

[0105] In some embodiments, the first request may also be referred to as a handover request or an LTM preparation request.

[0106] As mentioned above, at least one candidate cell may generate its own conditional configuration information. This implementation will be described below with reference to a specific example.

[0107] As an example, the first request may include a first candidate cell set. The first candidate cell set includes the first candidate cell and other candidate cells except the first candidate cell. The first candidate cell set is used by the first candidate cell to determine conditional configuration information for other candidate cells. The candidate cell list represented by the first candidate cell set may be referred to as a potential candidate cell set (list). When sending the first request, the source node informs each candidate cell in the first candidate cell set of the first candidate cell set, so that each candidate cell prepares conditional configuration information for other candidate cells.

[0108] As another example, after the source node receives the configuration information of the first candidate cell, the source node sends a second candidate cell set to the first candidate node, where the second candidate cell set includes the first candidate cell and other candidate cells except the first candidate cell, and the second candidate cell set is used by the first candidate cell to determine the conditional configuration information of other candidate cells. The second candidate cell set may be the same as the first candidate cell set. Alternatively, the second candidate cell set may be a subset of the first candidate cell set. The candidate cells in the second candidate cell set may be candidate cells determined to participate in the LTM process (correspondingly, the candidate cells in the first candidate cell set may be candidate cells potentially participating in the LTM process).

[0109] In some embodiments, the first conditional configuration information is included in the LTM configuration information.

[0110] In some other embodiments, the first condition configuration information is included in the measurement configuration information of the LTM. For example, the first condition configuration information is included in the measurement reference signal configuration information of the LTM.

[0111] In some further embodiments, the first conditional configuration information may also be included in the configuration information of multiple candidate cells. For example, the configuration information of the multiple candidate cells includes the configuration information of the first candidate cell. The first conditional configuration information is included in the configuration information of the first candidate cell. The first conditional configuration information may include the conditional configuration information of the first candidate cell, and the conditional configuration information of the first candidate cell is included in the configuration information of the first candidate cell.

[0112] As an example, when the conditional configuration information of the first candidate cell is included in the configuration information of the first candidate cell, the conditional configuration information of the first candidate cell is included in the measurement reporting configuration information of the first candidate cell.

[0113] In some embodiments, the first condition configuration information includes an evaluation condition for at least one candidate cell. Accordingly, the terminal device executes a layer 1 / layer 2 triggered mobility LTM process based on the first condition configuration information, including: the terminal device evaluates at least one candidate cell according to the first condition configuration information. For example, if the first condition configuration information is public configuration information applicable to all candidate cells, the terminal device can use a unified condition to evaluate at least one candidate cell. For another example, if the first condition configuration information is condition configuration information corresponding to a group of candidate cells (a group of candidate cells can belong to the same DU or the same CU), the terminal device can use the same condition when evaluating the same group of candidate cells, and can use different conditions when evaluating different groups of candidate cells. For another example, if the first condition configuration information is condition configuration information corresponding to each candidate cell, the terminal device can use different conditions to evaluate different candidate cells.

[0114] In some embodiments, before condition evaluation is performed on at least one candidate cell, at least one candidate cell (ie, a candidate cell to be evaluated) needs to be determined. The embodiment of the present application does not specifically limit the method for determining the candidate cell to be evaluated.

[0115] As an implementation method, the candidate cells to be evaluated are the candidate cells with conditional configuration information in the candidate cell set. For example, the terminal device can compare the candidate cell set of the LTM process with the first conditional configuration information, and determine the candidate cells with conditional configuration information in the candidate cell set as the candidate cells to be evaluated. For example, when the first conditional configuration information is public configuration information applicable to all candidate cells, the terminal device can use all candidate cells as candidate cells to be evaluated. For another example, when the first conditional configuration information includes conditional configuration information corresponding to a group of candidate cells (a group of candidate cells may belong to the same DU or the same CU), if a certain group of candidate cells has conditional configuration information, the terminal device can determine all candidate cells in the group of candidate cells as cells to be evaluated; if a certain group of candidate cells does not have conditional configuration information, the terminal device may not evaluate the group of candidate cells. For another example, when the first conditional configuration information includes conditional configuration information corresponding to each candidate cell, the terminal device can determine the candidate cells to be evaluated one by one according to whether each candidate cell has conditional configuration information.

[0116] As another implementation, the candidate cells to be evaluated may be determined based on the first indication information received by the terminal device. For example, the first indication information may be sent by the source node to the terminal device. In some embodiments, the first indication information may be displayed indication information sent by the source node. The first indication information may be used to indicate which candidate cells the terminal device needs to evaluate. The first indication information may be carried in an RRC message, a MAC CE, or downlink control information (DCI), for example. As an example, the first indication information is carried in a switching command (such as an LTM cell switch command) sent by the source node to the terminal device.

[0117] In some embodiments, at least one candidate cell includes a candidate primary cell (Pcell), and the first condition configuration information includes a first condition corresponding to the candidate Pcell (i.e., an evaluation condition for the candidate Pcell). It should be understood that if there are multiple candidate Pcells, the first condition may include conditions corresponding to each of the multiple candidate Pcells. In addition, the conditions corresponding to the candidate Pcell can also be understood as conditions corresponding to the MCG, i.e., the evaluation condition for the MCG.

[0118] In some embodiments, at least one candidate cell includes a candidate primary secondary cell (PScell), and the first condition configuration information includes a second condition corresponding to the candidate primary secondary cell (i.e., an evaluation condition of the candidate primary secondary cell). It should be understood that if there are multiple candidate secondary cells, the second condition may include conditions corresponding to each of the multiple candidate secondary cells. In addition, the conditions corresponding to the candidate primary secondary cells can also be understood as conditions corresponding to the SCG, i.e., the evaluation condition of the SCG.

[0119] In some embodiments, the first conditional configuration information includes conditional configuration information for determining the activation or deactivation state of a secondary cell (SCell). For example, the first configuration information includes condition a. If condition a is met, the terminal device determines that the SCell is in an activated state; if condition a is not met (or condition b is met), the terminal device determines that the SCell is in a deactivated state.

[0120] As an example, assuming that the terminal device executes the MCG LTM process and the MCG LTM configuration is associated with the MCG and SCG configurations, the first condition configuration information may include the first condition corresponding to the candidate primary cell and the second condition corresponding to the candidate primary and secondary cells, which are used to evaluate the candidate primary cell and the candidate primary and secondary cells, respectively.

[0121] The following describes in detail how the terminal device performs the LTM process based on the first condition and the second condition.

[0122] As an implementation method, if the candidate primary cell meets the first condition and the candidate primary and secondary cells meet the second condition, the terminal device performs the MCG LTM process without releasing the SCG, that is, the terminal device performs MCG LTM with SCG.

[0123] As another implementation manner, if the candidate primary cell meets the first condition and the candidate primary and secondary cells do not meet the second condition, the terminal device performs the MCG LTM process and releases, retains, or deactivates the SCG.

[0124] As another implementation manner, if the candidate primary cell does not meet the first condition and the candidate primary and secondary cells meet the second condition, the terminal device performs the SCG LTM process or does not perform cell switching.

[0125] As another implementation, if the candidate primary cell meets the first condition and the current primary and secondary cells of the terminal device meet the third condition, the terminal device performs the MCG LTM process and keeps the SCG unchanged during the MCG LTM process. For example, in a scenario that supports MCG LTM with SCG unchanged.

[0126] As another implementation, if the candidate primary cell meets the first condition and the current primary and secondary cells of the terminal device do not meet the third condition, the terminal device performs the MCG LTM process and switches or releases the SCG during the MCG LTM process. For example, in a scenario where MCG LTM with SCG unchanged is supported.

[0127] The above-mentioned conditions / events (such as the first condition, the second condition and / or the third condition mentioned above) include evaluating the beam measurement results of at least one source service cell and / or target service cell or candidate cell, wherein the evaluation of the beam measurement results may include comparing the UE measurement results with the network pre-configured threshold, and / or comparing the measurement results of the source cell and the candidate / target cell.

[0128] As an example, the first condition may be that the beam measurement result of the candidate primary cell is greater than or equal to a first threshold preconfigured by the network. The second condition may be that the beam measurement result of the candidate primary and secondary cells is greater than or equal to a second threshold preconfigured by the network. The third condition may be that the beam measurement result of the current primary and secondary cells is greater than a third threshold preconfigured by the network. The first, second, and third thresholds may be partially or completely the same or different.

[0129] In some embodiments, the source node sends the data of the terminal device to the target cell. For example, the source node may send the data of the terminal device to a node to which the target cell belongs, and the node to which the target cell belongs sends the data of the terminal device to the terminal device.

[0130] In some embodiments, the sending of data of the terminal device is based on one or more of the following triggers, indications or configurations (or the source node sends the data of the terminal device based on one or more of the following): receiving the second indication information sent by the terminal device; receiving the fourth indication information sent by the target cell; the measurement results reported by the terminal device; the CU corresponding to the source node receives the fifth indication information sent by the DU corresponding to the source node.

[0131] As an implementation, the terminal device may send second indication information to the source node. This second indication information may be used to instruct the source node to forward the terminal device's data to the target cell. The second indication information mentioned here may be proactively sent by the terminal device or sent by the terminal device based on a fourth condition. This fourth condition may, for example, include: at least one candidate cell meeting the condition indicated in the conditional configuration information.

[0132] As another implementation, the node to which the target cell belongs sends fourth indication information to the source node. The fourth indication information may be used to instruct the source node to forward the data of the terminal device to the target cell. Alternatively, the fourth indication information may be used to indicate that the terminal device has successfully switched to the target cell.

[0133] As another implementation, the sending of data by the terminal device is triggered, instructed, or configured based on a measurement result reported by the terminal device and received by the source node. For example, the measurement result reported by the terminal device may indicate when data forwarding has been performed to which candidate cell.

[0134] As another implementation method, the sending of data of the terminal device is based on the CU corresponding to the source node receiving the fifth indication information sent by the DU corresponding to the source node. The fifth indication information can be sent when the source node receives a switching command (that is, the fifth indication information is sent when triggering, indicating or configuring LTM). Alternatively, the fifth indication information is sent by the source node based on the measurement result reported by the terminal device (such as the L1 measurement result). For example, the measurement result reported by the terminal device may be the measurement result sent by the terminal device to the source node.

[0135] Taking the Inter-CU LTM scenario as an example, the CU corresponding to the source node receives the fifth indication information sent by the DU corresponding to the source node. The fifth indication information is used to instruct the CU corresponding to the source node to start data forwarding. The DU corresponding to the source node can send an indication to the CU corresponding to the source node when triggering, indicating, or configuring LTM, or the CU corresponding to the source node can also determine whether to start data forwarding and to which candidate cell to perform data forwarding based on the L1 measurement results reported by the terminal device.

[0136] In some embodiments, data of the terminal device is sent based on the Xn-U interface between the source node and the first candidate node.

[0137] In some embodiments, the Xn-U interface is determined based on address information of the Xn-U interface, and the address information of the Xn-U interface is determined by the source node in the preparation phase (or preparation switching phase) of the LTM process.

[0138] In some embodiments, the Xn-U interface may have an Xn-U address ID, and the source node and / or the first candidate node needs to know the Xn-U address ID of each candidate cell to perform data forwarding.

[0139] In some embodiments, if the first condition configuration information is used to trigger or instruct or configure the terminal device to execute CLTM, or the first condition configuration information is used to trigger or instruct or configure the terminal device to perform uplink synchronization and / or downlink synchronization with the candidate cell in advance, the terminal device does not report the measurement results of the candidate cell to the source node during the execution of LTM.

[0140] In some embodiments, if the first condition configuration information is used to trigger or instruct or configure the terminal device to report the measurement results of the candidate cell, the terminal device needs to report the measurement results of the candidate cell during the execution of the LTM process. Furthermore, in some embodiments, whether the terminal device reports the measurement results of the candidate cell can be determined based on protocol predefined information or indication information of the source node. For example, the source node can indicate through an indication field whether the terminal device needs to report the measurement results to the network side after the current condition is met or whether to execute the process of obtaining uplink synchronization and / or downlink synchronization in advance.

[0141] The following describes the embodiments of the present application in more detail with reference to the specific examples of Figures 5 and 6. It should be noted that the examples of Figures 5 and 6 are merely intended to help those skilled in the art understand the embodiments of the present application, and are not intended to limit the embodiments of the present application to the specific numerical values ​​or specific scenarios illustrated. It is obvious that those skilled in the art can make various equivalent modifications or changes based on the examples of Figures 5 and 6, and such modifications or changes also fall within the scope of the embodiments of the present application.

[0142] FIG5 is a flow chart illustrating a communication method according to an embodiment of the present application when applied to a CLTM scenario. The communication system in FIG5 may include a terminal device, a source node, candidate node 1, candidate node 2, and candidate node 3. Among them, one of candidate node 1, candidate node 2, and candidate node 3 may be the first candidate node described above. The terminal device, source node, and first candidate node may be specifically described above and will not be further described here. It should be understood that FIG5 only uses three candidate nodes as an example. In actual applications, the number of candidate nodes can be set as needed.

[0143] 5 , the communication method may include S510 - S570 .

[0144] In step S510, the terminal device sends the measurement result to the source node.

[0145] In some embodiments, the measurement result may be obtained by the terminal device performing cell measurement based on the configuration of the source node. For example, the measurement result may be an L3 measurement result.

[0146] In step S520, the source node sends a handover request message to each candidate node (candidate).

[0147] The handover request information may be sent based on a decision to trigger, configure, or indicate a CLTM based on measurement results of the terminal device. The handover request information may include a handover type indication, such as an indication that the type of the handover request is CLTM. The handover request information may be the first request described above. The candidate node may refer to a candidate cell or a CU / base station to which the candidate cell belongs.

[0148] In step S530 , the source node receives the configuration of the candidate cell sent by each candidate node.

[0149] The candidate cell configuration can also be referred to as handover request feedback. In some embodiments, the candidate cell configuration can be sent to the source node via LTM configuration. The mechanism for each candidate node to send LTM is similar. Taking candidate node 1 as an example, after candidate node 1 receives the handover request information, the CU to which candidate node 1 belongs can send the handover request information to the DU to which the candidate cell belongs. The DU generates the corresponding configuration and sends it to the CU. The CU combines the candidate cell configurations generated by at least one DU and sends them to the source node.

[0150] Optionally, the handover request information may include a list of potential candidate cells. The source node may inform each candidate cell of the list of potential candidate cells during the first (or initial) handover request, so that the candidate cell can prepare conditional configuration information for other candidate cells. The list of potential candidate cells may be the first candidate cell set described above.

[0151] In some embodiments, the conditional configuration information may be generated by a candidate cell or a candidate node.

[0152] As shown in FIG5 , after step S530 , step S531 and step S532 may be further included.

[0153] In step S531: the source node sends an LTM configuration update to each candidate node.

[0154] The LTM configuration update includes a determined candidate cell list, and the LTM configuration update is used to inform each candidate cell of the determined candidate cell list to prepare conditional configuration information.

[0155] In step S532: the source node receives the condition configuration information sent by each candidate node.

[0156] In other embodiments, the conditional configuration information may be generated by a source node. After receiving the configuration of at least one candidate cell, the source node may directly generate the conditional configuration information and send it to the terminal device.

[0157] Optionally, the conditional configuration information and other configuration information may be sent to the terminal device via one message or multiple messages.

[0158] The above-mentioned condition configuration information may be the first condition configuration information mentioned above.

[0159] Continuing to refer to FIG. 5 , in step S540 , the source node sends an RRC reconfiguration message to the terminal device.

[0160] The RRC reconfiguration message may include configuration and / or conditional configuration information of each candidate cell.

[0161] a. The conditional configuration information includes conditional configuration information for triggering, configuring, or indicating conditional LTM and / or conditional configuration information for triggering, configuring, or indicating a terminal device to report LTM candidate cell measurement results and / or conditional configuration information for triggering, configuring, or indicating an early acquisition of an uplink synchronization process.

[0162] The conditional configuration information can be configured in the following ways: the conditional configuration information is a common configuration information, applicable to all candidate cells, and configured by the source node; the conditional configuration information is different for each candidate cell and is generated by each candidate cell itself; the conditional configuration information can be applicable to a group of candidate cells, for example, the conditional configuration information corresponding to the cells under the same CU / DU is the same.

[0163] b. The condition configuration information includes evaluation conditions for at least one candidate cell.

[0164] c. The conditional configuration information configuration is included in the LTM configuration or the measurement reference signal configuration of the LTM, or in the configuration of each candidate cell. If the conditional configuration information configuration is included in the configuration of each candidate cell, it may be included in the measurement reporting configuration of the candidate cell.

[0165] d. For CLTM, if the conditional configuration information is used to trigger, configure, or instruct the execution of conditional LTM or to obtain early uplink synchronization, the terminal device does not need to report the measurement results. If the conditional configuration information is used to trigger, configure, or instruct the terminal device to report the measurement results of LTM candidate cells, the terminal device needs to trigger, configure, or instruct the reporting of the measurement results. The terminal device can determine whether to trigger, configure, or instruct the reporting of measurement results based on protocol agreement or network indication. For example, an indication field indicates whether the terminal device needs to report the measurement results to the network or perform the process of obtaining early uplink / downlink synchronization after the current condition is met.

[0166] In step S550, the terminal device evaluates candidate cells.

[0167] Among them, the terminal device can evaluate the candidate cell based on the conditional configuration information of the serving cell (source node or currently accessed candidate cell / serving cell).

[0168] Optionally, the terminal device determines candidate cells to be evaluated before each evaluation, including comparing the candidate cell list with the condition configuration information, and determining candidate cells in the candidate cell list that have the condition configuration information for evaluation.

[0169] Optionally, the terminal device may determine the candidate cells to be evaluated based on network display indications, such as by instructing the terminal device via RRC messages or MAC CE or DCI which candidate cells to evaluate.

[0170] Optionally, the terminal device's evaluation of candidate cells includes evaluating candidate Pcells and / or candidate PScells. For example, the MCG LTM configuration is associated with the MCG and SCG configurations, and the corresponding conditional configuration information may also include evaluation conditions for both the Pcell and the candidate PScell. For example, if both the Pcell and the PScell ​​(candidate or current serving Pscell) meet the conditions, the terminal device may execute MCG LTM with SCG. If only the PCell meets the conditions, MCG LTM is executed. If only the PSCell meets the conditions, the terminal device does not perform switching or SCG LTM. For another example, to support the scenario of MCG LTM with SCG unchanged, in addition to evaluating the MCG conditions to determine the candidate cells, the terminal device also needs to determine whether the conditions of the current serving SCG are met. If so, the SCG may remain unchanged. If not, the SCG may be switched or released. Alternatively, based on the conditions, it may be determined whether the status of the current serving SCG is activated or deactivated, or whether the status of the target SCG is activated or deactivated.

[0171] In step S560, the terminal device executes CLTM.

[0172] In step S570, the source node starts forwarding data to the target cell.

[0173] The source node and / or candidate cells perform data forwarding based on the XN-U address ID. The XN-U address ID can be obtained during the handover preparation phase. The source node and / or candidate cells need to know the XN-U address ID of each candidate cell to perform data forwarding.

[0174] The conditions for the source node to start forwarding data include receiving an indication from the target cell or receiving indication information from the terminal device.

[0175] The target cell instructing the source node to start data forwarding includes the target cell instructing the source node that the handover is successful.

[0176] The terminal device instructs the source node based on conditional judgment, for example, when at least one candidate cell meets the condition, the terminal device instructs the source node to start data forwarding; or the source node device can also determine when and to which candidate cell data forwarding has been performed based on the measurement report of the terminal device.

[0177] After the terminal device is successfully switched, step S550 is repeated to perform a continuous LTM switching process.

[0178] FIG6 is a flow chart of a communication method according to an embodiment of the present application when applied to an inter-CU LTM scenario. Referring to FIG6 , the communication method may include S610 to S670.

[0179] Step S610: The terminal device sends the measurement result to the source node.

[0180] The relevant features in step S610 are similar to those in step S510 in the embodiment of FIG. 5 , and are not described again here.

[0181] In step S620, the source node sends a handover request message to each candidate node (candidate).

[0182] The relevant features in step S620 are similar to the features in step S520 in the embodiment of Figure 5. The difference is that the switching type indication in this switching request information is different from the embodiment shown in Figure 5. The switching type indication in this switching request information can indicate that the type of this switching request is LTM.

[0183] In step S630, the source node receives the configuration of the candidate cell sent by each candidate node.

[0184] In some embodiments, the conditional configuration information may be generated by a candidate cell or a candidate node. Based on this, as shown in FIG6 , after step S630 , steps S631 and S632 may be further included.

[0185] In step S631: the source node sends an LTM configuration update to each candidate node.

[0186] In step S632: the source node receives the conditional configuration information sent by each candidate node.

[0187] The relevant features in step S630, step S631 and step S632 are similar to the similar features in step S530, step S631 and step S632 in the embodiment of Figure 5, and are not repeated here.

[0188] Continuing to refer to FIG. 6 , in step S640 , the source node sends an RRC reconfiguration message to the terminal device.

[0189] The RRC reconfiguration message may include configuration and / or conditional configuration information of each candidate cell.

[0190] a. The conditional configuration information includes conditional configuration information for triggering, configuring, or instructing a terminal device to report LTM candidate cell measurement results and / or conditional configuration information for triggering, configuring, or instructing an early acquisition of an uplink synchronization process.

[0191] The possible ways of configuring the conditional information are the same as the possible ways of configuring the conditional information in step S640 of the embodiment in FIG. 5 , and are not described in detail here.

[0192] b. The condition configuration information includes evaluation conditions for at least one candidate cell.

[0193] c. The conditional configuration information configuration is included in the LTM configuration or the measurement reference signal configuration of the LTM, or in the configuration of each candidate cell. If the conditional configuration information configuration is included in the configuration of each candidate cell, it may be included in the measurement reporting configuration of the candidate cell.

[0194] In step S650, the terminal device evaluates candidate cells.

[0195] Among them, the terminal device can evaluate the candidate cell based on the conditional configuration information of the serving cell (source node or currently accessed candidate cell / serving cell).

[0196] Optionally, the terminal device determines candidate cells to be evaluated before each evaluation, including comparing the candidate cell list with the condition configuration information, and determining candidate cells in the candidate cell list that have the condition configuration information for evaluation.

[0197] Optionally, the terminal device may determine the candidate cells to be evaluated based on network display instructions, such as instructing the terminal device which candidate cells to evaluate through RRC messages or MAC CE or DCI; optionally, the network may also indicate the candidate cells to be evaluated through an LTM cell switching command.

[0198] As shown in FIG6 , step S650 may further include steps S651 - S654 .

[0199] In step S651 , the terminal device performs L1 measurement.

[0200] In step S652, the terminal device determines whether the reporting conditions of the measurement results are met. If the conditions are met, step S653 is executed.

[0201] In some embodiments, the terminal device may determine whether to report the L1 measurement result based on the condition configuration information related to the measurement result in the condition configuration information.

[0202] In step S653, the terminal device reports the L1 measurement result to the source node.

[0203] In step S654, the source node sends a cell switch command to the terminal device.

[0204] In some embodiments, the source node may determine whether to send a cell switching command to the terminal device based on the conditional configuration information.

[0205] In step S660, the source node starts forwarding data to the target cell.

[0206] The source node and / or candidate cells perform data forwarding based on the XN-U address ID. The XN-U address ID can be obtained during the handover preparation phase. The source node and / or candidate cells need to know the XN-U address ID of each candidate cell to perform data forwarding.

[0207] The source serving cell performing data forwarding includes the source CU receiving indication information sent by the DU of the source serving cell, where the indication information is used to instruct the CU to start data forwarding. The DU instructing the CU may be when LTM is triggered, configured, or indicated, or may be based on L1 measurement results reported by the UE to determine whether to start data forwarding and to which candidate cell to perform data forwarding.

[0208] In step S670, the terminal device executes LTM.

[0209] After the terminal device is successfully switched, step S650 is repeated to perform a continuous LTM switching process.

[0210] The communication system in Figures 5-6 may include a terminal device, a source node, candidate node 1, candidate node 2, and candidate node 3. Among these, one of candidate node 1, candidate node 2, and candidate node 3 may be the first candidate node described above. The terminal device, source node, and first candidate node are described in detail above and will not be further described here. It should be understood that Figures 5-6 illustrate only three candidate nodes. In actual applications, the number of candidate nodes can be customized as needed.

[0211] The LTM process in the embodiment of FIG. 5 and the embodiment of FIG. 6 includes inter-CU LTM and intra-CU LTM, and MCG LTM or SCG LTM is applicable.

[0212] The above-mentioned condition configuration information may include only the conditions for evaluating candidate / target Pcells, or may include the conditions for both Pcells and PSCells.

[0213] The above-mentioned conditions / events include evaluating the beam measurement results of at least one source service cell and / or target service cell or candidate cell, wherein evaluating the beam measurement results may include comparing the UE measurement results with the network pre-configured threshold, and / or comparing the measurement results of the source cell and the candidate / target cell.

[0214] The method embodiment of the present application is described in detail above in conjunction with Figures 1 to 6 . The device embodiment of the present application is described in detail below in conjunction with Figures 7 to 10 . It should be understood that the description of the method embodiment corresponds to the description of the device embodiment. Therefore, for parts not described in detail, reference can be made to the above method embodiment.

[0215] FIG7 is a schematic block diagram of a terminal device provided in an embodiment of the present application. The terminal device 700 shown in FIG7 can be any of the terminal devices described above. The terminal device 700 can include a receiving unit 710 and an executing unit 720.

[0216] The receiving unit 710 is configured to receive first condition configuration information from a source node.

[0217] The executing unit 720 is configured to execute a layer 1 / layer 2 triggered mobility LTM process based on the first condition configuration information.

[0218] In some possible implementations, the execution unit is used to perform one or more of the following operations based on the first condition configuration information: executing conditional LTM; reporting the measurement results of the candidate cell to the source node; performing uplink synchronization and / or downlink synchronization with the candidate cell in advance; performing data forwarding; and determining the secondary cell group SCG processing method.

[0219] In some possible implementations, the first conditional configuration information is common configuration information applicable to all candidate cells; or, the first conditional configuration information includes conditional configuration information corresponding to at least one candidate cell; or, the first conditional configuration information includes conditional configuration information corresponding to at least one group of candidate cells.

[0220] In some possible implementations, the group of candidate cells belongs to the same distribution unit DU; or, the group of candidate cells belongs to the same CU.

[0221] In some possible implementations, the first conditional configuration information is generated by the source node; or, the first conditional configuration information is generated by the node to which the service cell of the terminal device belongs; or, the first conditional configuration information includes conditional configuration information generated by one or more candidate cells.

[0222] In some possible implementations, the first condition configuration information is included in the LTM configuration information; or, the first condition configuration information is included in the measurement configuration information of the LTM; or, the first condition configuration information is included in the configuration information of the first candidate cell.

[0223] In some possible implementations, the executing unit 720 is further configured to: evaluate at least one candidate cell according to the first condition configuration information.

[0224] In some possible implementations, the at least one candidate cell is a candidate cell in a candidate cell set that has conditional configuration information; or, the at least one candidate cell is determined based on first indication information received by the terminal device.

[0225] In some possible implementations, the first indication information is carried in a switching command received by the terminal device.

[0226] In some possible implementations, the at least one candidate cell includes a candidate primary cell, and the first condition configuration information includes a first condition corresponding to the candidate primary cell; and / or, the at least one candidate cell includes a candidate primary and secondary cell, and the first condition configuration information includes a second condition corresponding to the candidate primary and secondary cell.

[0227] In some possible implementations, if the candidate primary cell satisfies the first condition and the candidate primary and secondary cells satisfy the second condition, the terminal device performs the primary cell group MCG LTM process without releasing the SCG; or, if the candidate primary cell satisfies the first condition and the candidate primary and secondary cells do not satisfy the second condition, the terminal device performs the MCG LTM process and releases or retains or deactivates the SCG; or, if the candidate primary cell does not satisfy the first condition and the candidate primary and secondary cells satisfy the second condition, the terminal device performs the SCG LTM process or does not perform cell switching; or, if the candidate primary cell satisfies the first condition and the current primary and secondary cells of the terminal device satisfy the third condition, the terminal device performs the MCG LTM process and keeps the SCG unchanged during the execution of the MCG LTM process; or, if the candidate primary cell satisfies the first condition and the current primary and secondary cells of the terminal device do not satisfy the third condition, the terminal device performs the MCG LTM process and switches or releases the SCG during the execution of the MCG LTM process.

[0228] In some possible implementations, the terminal device further includes: a sending unit, configured to send second indication information to the source node, where the second indication information is used to instruct the source node to forward the data of the terminal device to a target cell.

[0229] In some possible implementations, the sending unit sends the second indication information based on a fourth condition, where the fourth condition includes a condition that at least one candidate cell satisfies the condition indicated by the conditional configuration information.

[0230] In some possible implementations, the LTM process is a conditional LTM process. If the first conditional configuration information is used to configure the terminal device to perform conditional LTM, or the first conditional configuration information is used to configure the terminal device to perform uplink synchronization and / or downlink synchronization with the candidate cell in advance, then the terminal device does not report the measurement results of the candidate cell to the source node during the execution of the LTM process; and / or if the first conditional configuration information is used to configure the terminal device to report the measurement results of the candidate cell, then the terminal device reports the measurement results of the candidate cell during the execution of the LTM process.

[0231] In some possible implementations, whether to report the measurement result of the candidate cell is determined based on protocol predefined information or indication information of the source node.

[0232] In some possible implementations, the LTM process includes one of the following: an LTM process between CUs, an LTM process within a CU, an MCG LTM process, and an SCG LTM process.

[0233] In some possible implementations, the first condition configuration information is carried in an RRC reconfiguration message.

[0234] Figure 8 is a schematic block diagram of a network device according to an embodiment of the present application. The network device 800 shown in Figure 8 may be the source node described above. The source node may be a source cell; alternatively, the source node may be a centralized unit (CU) or a base station to which the source cell belongs. The network device 800 may include a sending unit 810.

[0235] The sending unit 810 is configured to send first condition configuration information to a terminal device, where the first condition configuration information is used for the terminal device to perform a layer 1 / layer 2 triggered mobility LTM process.

[0236] In some possible implementations, the first conditional configuration information is used to trigger the terminal device to perform one or more of the following operations: execute conditional LTM; report the measurement results of the candidate cell to the source node; perform uplink synchronization and / or downlink synchronization with the candidate cell in advance; perform data forwarding; and determine the secondary cell group SCG processing method.

[0237] In some possible implementations, the first conditional configuration information is common configuration information applicable to all candidate cells; or, the first conditional configuration information includes conditional configuration information corresponding to at least one candidate cell; or, the first conditional configuration information includes conditional configuration information corresponding to at least one group of candidate cells.

[0238] In some possible implementations, the group of candidate cells belong to the same distribution unit DU; or, the group of candidate cells belong to the same CU.

[0239] In some possible implementations, the first conditional configuration information is generated by the source node; or, the first conditional configuration information is generated by the node to which the service cell of the terminal device belongs; or, the first conditional configuration information includes conditional configuration information generated by one or more candidate cells.

[0240] In some possible implementations, the first condition configuration information is included in the LTM configuration information; or, the first condition configuration information is included in the measurement configuration information of the LTM; or, the first condition configuration information is included in the configuration information of the first candidate cell.

[0241] In some possible implementations, the sending unit is also used to: send a first request to a first candidate node, the first request being used to request the first candidate node to provide configuration information of a first candidate cell; wherein the first candidate node is the first candidate cell; or, the first candidate node is the CU or base station to which the first candidate cell belongs.

[0242] In some possible implementations, the first request includes third indication information, where the third indication information is used to indicate that the type of the LTM process is: LTM, conditional LTM, LTM between CUs, or LTM within a CU.

[0243] In some possible implementations, the first request includes a first candidate cell set, the first candidate cell set includes the first candidate cell and other candidate cells except the first candidate cell, and the first candidate cell set is used by the first candidate cell to determine conditional configuration information of the other candidate cells.

[0244] In some possible implementations, the sending unit is further used to: after the receiving unit receives the configuration information of the first candidate cell, send a second candidate cell set to the first candidate node, the second candidate cell set including the first candidate cell and other candidate cells except the first candidate cell, and the second candidate cell set is used by the first candidate cell to determine the conditional configuration information of the other candidate cells.

[0245] In some possible implementations, the sending unit is further configured to: send the data of the terminal device to a target cell.

[0246] In some possible implementations, the source node sends data of the terminal device based on one or more of the following: receiving second indication information sent by the terminal device; receiving fourth indication information sent by the target cell; measurement results reported by the terminal device; and the CU corresponding to the source node receiving fifth indication information sent by the DU corresponding to the source node.

[0247] In some possible implementations, the second indication information is sent by the terminal device based on a fourth condition, where the fourth condition includes that at least one candidate cell satisfies the condition indicated by the condition configuration information.

[0248] In some possible implementations, the fourth indication information is used to indicate that the terminal device has successfully switched to the target cell.

[0249] In some possible implementations, the fifth indication information is sent by the source node when receiving a switching command; or, the fifth indication information is sent by the source node based on a measurement result reported by the terminal device.

[0250] In some possible implementations, the data of the terminal device is sent based on the Xn-U interface between the source node and the target cell.

[0251] In some possible implementations, the Xn-U interface is determined based on address information of the Xn-U interface, and the address information of the Xn-U interface is determined by the source node in a preparation phase of the LTM process.

[0252] In some possible implementations, the LTM process includes one of the following: an LTM process between CUs, an LTM process within a CU, a master cell group MCG LTM process, and an SCG LTM process.

[0253] In some possible implementations, the first condition configuration information is carried in an RRC reconfiguration message.

[0254] Figure 9 is a schematic block diagram of another network device provided in an embodiment of the present application. The network device 900 shown in Figure 9 may be the first candidate node described above. The first candidate node is a first candidate cell; alternatively, the first candidate node is a centralized unit (CU) or a base station to which the first candidate cell belongs. The network device 900 may include a sending unit 910.

[0255] The sending unit 910 is configured to send conditional configuration information to a source node, where the conditional configuration information is used for a terminal device to perform a layer 1 / layer 2 triggered mobility LTM process.

[0256] In some possible implementations, the conditional configuration information is used by the terminal device to perform one or more of the following operations: executing conditional LTM; reporting the measurement results of the first candidate cell to the source node; performing uplink synchronization and / or downlink synchronization with the first candidate cell in advance; performing data forwarding; and determining the secondary cell group SCG processing method.

[0257] In some possible implementations, the conditional configuration information includes conditional configuration information corresponding to the first candidate cell; or, the conditional configuration information includes conditional configuration information corresponding to a group of candidate cells.

[0258] In some possible implementations, the group of candidate cells belong to the same distribution unit DU; or, the group of candidate cells belong to the same CU.

[0259] In some possible implementations, the first condition configuration information is included in the LTM configuration information; or, the first condition configuration information is included in the measurement configuration information of the LTM; or, the first condition configuration information is included in the configuration information of the first candidate cell.

[0260] In some possible implementations, the network device further includes: a receiving unit, configured to receive a first request sent by the source node, where the first request is used to request the first candidate node to provide configuration information of the first candidate cell.

[0261] In some possible implementations, the first request includes third indication information, where the third indication information is used to indicate that the type of the LTM process is: LTM, conditional LTM, LTM between CUs, or LTM within a CU.

[0262] In some possible implementations, the first request includes a first candidate cell set, the first candidate cell set includes the first candidate cell and other candidate cells except the first candidate cell, and the first candidate cell set is used by the first candidate cell to determine conditional configuration information of the other candidate cells.

[0263] In some possible implementations, the receiving unit is further used to: after the sending unit sends the configuration information of the first candidate cell to the source node, receive a second candidate cell set sent by the source node, the second candidate cell set including the first candidate cell and other candidate cells except the first candidate cell, and the second candidate cell set is used by the first candidate cell to determine the conditional configuration information of the other candidate cells.

[0264] In some possible implementations, the first candidate node is a target cell or a CU or a base station to which the target cell belongs, and the receiving unit is further used to: receive data of the terminal device from the source node.

[0265] In some possible implementations, before the receiving unit receives the data of the terminal device from the source node, the sending unit is further used to: send fourth indication information to the source node, and the fourth indication information is used to trigger the source node to start sending the data of the terminal device to the target cell.

[0266] In some possible implementations, the fourth indication information is used to indicate that the terminal device has successfully switched to the target cell.

[0267] In some possible implementations, the data of the terminal device is sent based on the Xn-U interface between the source node and the first candidate node.

[0268] In some possible implementations, the Xn-U interface is determined based on address information of the Xn-U interface, and the address information of the Xn-U interface is determined by the source node in a preparation phase of the LTM process.

[0269] In some possible implementations, the LTM process includes one of the following: an LTM process between CUs, an LTM process within a CU, a master cell group MCG LTM process, and an SCG LTM process.

[0270] In some possible implementations, the first condition configuration information is carried in an RRC reconfiguration message.

[0271] Figure 10 is a schematic block diagram of a communication device according to an embodiment of the present application. The dashed lines in Figure 10 indicate that the unit or module is optional. The device 1000 may be used to implement the method described in the above method embodiment. The device 1000 may be a chip, a terminal device, or a network device.

[0272] The device 1000 may include one or more processors 1010. The processor 1010 may support the device 1000 to implement the method described in the method embodiment above. The processor 1010 may be a general-purpose processor or a special-purpose processor. For example, the processor may be a central processing unit (CPU). Alternatively, the processor may be another general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic device, discrete hardware component, etc. The general-purpose processor may be a microprocessor or the processor may be any conventional processor, etc.

[0273] The apparatus 1000 may further include one or more memories 1020. The memories 1020 store programs that can be executed by the processor 1010, causing the processor 1010 to perform the methods described in the above method embodiments. The memories 1020 may be independent of the processor 1010 or integrated into the processor 1010.

[0274] The apparatus 1000 may further include a transceiver 1030. The processor 1010 may communicate with other devices or chips via the transceiver 1030. For example, the processor 1010 may transmit and receive data with other devices or chips via the transceiver 1030.

[0275] The present application also provides a computer-readable storage medium for storing a program. The computer-readable storage medium can be applied to a terminal or network device provided in the present application, and the program enables a computer to execute the method performed by the terminal or network device in each embodiment of the present application.

[0276] The present application also provides a computer program product. The computer program product includes a program. The computer program product can be applied to a terminal or network device provided in the present application, and the program causes a computer to execute the method performed by the terminal or network device in each embodiment of the present application.

[0277] The embodiments of the present application also provide a computer program. The computer program can be applied to the terminal or network device provided in the embodiments of the present application, and the computer program enables a computer to execute the method performed by the terminal or network device in each embodiment of the present application.

[0278] It should be understood that the terms "system" and "network" in this application can be used interchangeably. In addition, the terms used in this application are only used to explain the specific embodiments of this application and are not intended to limit this application. The terms "first", "second", "third", and "fourth" in the specification and claims of this application and the accompanying drawings are used to distinguish different objects rather than to describe a specific order. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions.

[0279] In the embodiments of this application, the term "indication" may refer to a direct indication, an indirect indication, or an indication of an association. For example, "A indicates B" may refer to a direct indication of B, e.g., B can obtain information through A; it may refer to an indirect indication of B, e.g., A indicates C, e.g., B can obtain information through C; or it may refer to an association between A and B.

[0280] In the embodiments of this application, the term "include" can refer to direct inclusion or indirect inclusion. Alternatively, the term "include" in the embodiments of this application can be replaced with "indicates" or "is used to determine." For example, "A includes B" can be replaced with "A indicates B" or "A is used to determine B."

[0281] In the embodiment of the present application, "B corresponding to A" means that B is associated with A and B can be determined based on A. However, it should be understood that determining B based on A does not mean determining B based solely on A, but B can also be determined based on A and / or other information.

[0282] In the embodiments of the present application, the term "corresponding" may indicate a direct or indirect correspondence between the two, or an association relationship between the two, or a relationship between indication and indication, configuration and configuration, etc.

[0283] In the embodiments of the present application, "pre-definition" or "pre-configuration" may be implemented by pre-storing corresponding codes, tables, or other methods that can be used to indicate relevant information in a device (e.g., a terminal device and a network device). The present application does not limit the specific implementation method. For example, pre-definition may refer to information defined in a protocol.

[0284] In the embodiments of the present application, the “protocol” may refer to a standard protocol in the communications field, for example, it may include an LTE protocol, an NR protocol, and related protocols used in future communication systems, and the present application does not limit this.

[0285] In the embodiments of this application, the term "and / or" is simply a description of the association relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this document generally indicates that the related objects are in an "or" relationship.

[0286] In various embodiments of the present application, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0287] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0288] The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0289] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0290] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from one website, computer, server or data center to another website, computer, server or data center via a wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) method. The computer-readable storage medium can be any available medium that can be read by a computer or a data storage device such as a server or data center that includes one or more available media integrated therein. The available medium may be a magnetic medium (eg, a floppy disk, a hard disk, a magnetic tape), an optical medium (eg, a digital versatile disc (DVD)), or a semiconductor medium (eg, a solid state disk (SSD)).

[0291] The above description is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of this application. Therefore, the scope of protection of this application should be based on the scope of protection of the claims.

Claims

1. A communication method, characterized in that: include: The terminal device receives first condition configuration information from the source node; The terminal device performs a layer 1 / layer 2 triggered mobility LTM process based on the first condition configuration information.

2. The method according to claim 1, characterized in that The terminal device executing the layer 1 / layer 2 triggered mobility LTM process based on the first condition configuration information includes: The terminal device performs one or more of the following operations based on the first condition configuration information: Execute conditional LTM; Reporting the measurement results of the candidate cells to the source node; Perform uplink synchronization and / or downlink synchronization with the candidate cell in advance; Perform data forwarding; Determine the SCG processing method.

3. The method according to claim 1 or 2, characterized in that: The first condition configuration information is common configuration information applicable to all candidate cells; or, The first condition configuration information includes condition configuration information corresponding to at least one candidate cell; or, The first condition configuration information includes condition configuration information corresponding to at least one group of candidate cells.

4. The method according to claim 3, wherein: The group of candidate cells belongs to the same distribution unit DU; or, The group of candidate cells belongs to the same CU.

5. The method according to any one of claims 1 to 4, characterized in that: The first condition configuration information is generated by the source node; or, The first condition configuration information is generated by a node to which a serving cell of the terminal device belongs; or, The first condition configuration information includes condition configuration information generated by one or more candidate cells.

6. The method according to any one of claims 1 to 5, characterized in that: The first condition configuration information is included in the LTM configuration information; or, The first condition configuration information is included in the measurement configuration information of the LTM; or, The first condition configuration information is included in the configuration information of the first candidate cell.

7. The method according to any one of claims 1 to 6, characterized in that The terminal device performing the layer 1 / layer 2 triggered mobility LTM process based on the first condition configuration information further includes: The terminal device evaluates at least one candidate cell according to the first condition configuration information.

8. The method according to claim 7, wherein: The at least one candidate cell is a candidate cell in the candidate cell set that has conditional configuration information; or, The at least one candidate cell is determined based on the first indication information received by the terminal device.

9. The method according to claim 8, characterized in that The first indication information is carried in the switching command received by the terminal device.

10. The method according to any one of claims 7 to 9, characterized in that: The at least one candidate cell includes a candidate primary cell, and the first condition configuration information includes a first condition corresponding to the candidate primary cell; and / or, The at least one candidate cell includes a candidate primary and secondary cell, and the first condition configuration information includes a second condition corresponding to the candidate primary and secondary cell.

11. The method according to claim 10, characterized in that The method further comprises: If the candidate primary cell meets the first condition and the candidate primary and secondary cells meet the second condition, the terminal device performs the primary cell group MCG LTM process without releasing the SCG; or, If the candidate primary cell satisfies the first condition and the candidate primary and secondary cells do not satisfy the second condition, the terminal device performs the MCG LTM process and releases, retains, or deactivates the SCG; or, If the candidate primary cell does not meet the first condition, and the candidate primary and secondary cells meet the second condition, the terminal device performs the SCG LTM process or does not perform cell switching; or, If the candidate primary cell satisfies the first condition and the current primary and secondary cells of the terminal device meet the third condition, the terminal device performs an MCG LTM process and keeps the SCG unchanged during the execution of the MCG LTM process; or If the candidate primary cell meets the first condition and the current primary and secondary cells of the terminal device do not meet the third condition, the terminal device executes the MCG LTM process and switches or releases the SCG during the execution of the MCG LTM process.

12. The method according to any one of claims 1 to 11, characterized in that The method further comprises: The terminal device sends second indication information to the source node, where the second indication information is used to instruct the source node to forward the data of the terminal device to the target cell.

13. The method according to claim 12, characterized in that The terminal device sends the second indication information based on a fourth condition, where the fourth condition includes that at least one candidate cell meets the condition indicated by the condition configuration information.

14. The method according to any one of claims 1 to 13, characterized in that The LTM process is a conditional LTM process, and the method further includes: If the first condition configuration information is used to configure the terminal device to perform conditional LTM, or the first condition configuration information is used to configure the terminal device to perform uplink synchronization and / or downlink synchronization with the candidate cell in advance, the terminal device does not report the measurement result of the candidate cell to the source node during the execution of the LTM process; and / or If the first condition configuration information is used to configure the terminal device to report the measurement result of the candidate cell, the terminal device reports the measurement result of the candidate cell during the execution of the LTM process.

15. The method according to claim 14, characterized in that Whether to report the measurement result of the candidate cell is determined based on protocol predefined information or indication information of the source node.

16. The method according to any one of claims 1 to 15, characterized in that The LTM process includes one of the following: an LTM process between CUs, an LTM process within a CU, an MCG LTM process, and an SCG LTM process.

17. The method according to any one of claims 1 to 16, characterized in that The first condition configuration information is carried in an RRC reconfiguration message.

18. A communication method, characterized in that: include: The source node sends first condition configuration information to the terminal device, where the first condition configuration information is used for the terminal device to perform a layer 1 / layer 2 triggered mobility LTM process; The source node is a source cell; or the source node is a centralized unit CU or a base station to which the source cell belongs.

19. The method according to claim 18, characterized in that The first condition configuration information is used by the terminal device to perform one or more of the following operations: Execute conditional LTM; Reporting the measurement results of the candidate cells to the source node; Perform uplink synchronization and / or downlink synchronization with the candidate cell in advance; Perform data forwarding; Determine the SCG processing method.

20. The method according to claim 18 or 19, characterized in that: The first condition configuration information is common configuration information applicable to all candidate cells; or, The first condition configuration information includes condition configuration information corresponding to at least one candidate cell; or, The first condition configuration information includes condition configuration information corresponding to at least one group of candidate cells.

21. The method according to claim 20, characterized in that: The group of candidate cells belongs to the same distribution unit DU; or, The group of candidate cells belongs to the same CU.

22. The method according to any one of claims 18 to 21, characterized in that: The first condition configuration information is generated by the source node; or, The first condition configuration information is generated by a node to which a serving cell of the terminal device belongs; or, The first condition configuration information includes condition configuration information generated by one or more candidate cells.

23. The method according to any one of claims 18 to 22, characterized in that: The first condition configuration information is included in the LTM configuration information; or, The first condition configuration information is included in the measurement configuration information of the LTM; or, The first condition configuration information is included in the configuration information of the first candidate cell.

24. The method according to any one of claims 18 to 23, characterized in that The method further comprises: The source node sends a first request to the first candidate node, where the first request is used to request the first candidate node to provide configuration information of the first candidate cell; The first candidate node is the first candidate cell; or the first candidate node is the CU or base station to which the first candidate cell belongs.

25. The method according to claim 24, characterized in that The first request includes third indication information, where the third indication information is used to indicate that the type of the LTM process is: LTM, conditional LTM, LTM between CUs, or LTM within a CU.

26. The method according to claim 24 or 25, characterized in that The first request includes a first candidate cell set, which includes the first candidate cell and other candidate cells except the first candidate cell. The first candidate cell set is used by the first candidate cell to determine conditional configuration information of the other candidate cells.

27. The method according to claim 24 or 25, characterized in that The method further comprises: After the source node receives the configuration information of the first candidate cell, the source node sends a second candidate cell set to the first candidate node, where the second candidate cell set includes the first candidate cell and other candidate cells except the first candidate cell, and the second candidate cell set is used by the first candidate cell to determine conditional configuration information of the other candidate cells.

28. The method according to any one of claims 18 to 27, characterized in that The method further comprises: The source node sends the data of the terminal device to the target cell.

29. The method according to claim 28, characterized in that The source node sends the data of the terminal device based on one or more of the following: receiving second indication information sent by the terminal device; receiving fourth indication information sent by the target cell; The measurement results reported by the terminal device; The CU corresponding to the source node receives the fifth indication information sent by the DU corresponding to the source node.

30. The method according to claim 29, wherein The second indication information is sent by the terminal device based on a fourth condition, and the fourth condition includes that at least one candidate cell meets the condition indicated by the condition configuration information.

31. The method according to claim 29, wherein The fourth indication information is used to indicate that the terminal device has successfully switched to the target cell.

32. The method according to claim 29, wherein The fifth indication information is sent by the source node when receiving a switching command; or, the fifth indication information is sent by the source node based on a measurement result reported by the terminal device.

33. The method according to any one of claims 28 to 32, characterized in that The data of the terminal device is sent based on the Xn-U interface between the source node and the target cell.

34. The method according to claim 33, wherein The Xn-U interface is determined based on address information of the Xn-U interface, and the address information of the Xn-U interface is determined by the source node in the preparation stage of the LTM process.

35. The method according to any one of claims 18 to 34, characterized in that The LTM process includes one of the following: LTM process between CUs, LTM process within a CU, master cell group MCG LTM process, and SCG LTM process.

36. The method according to any one of claims 18 to 35, characterized in that The first condition configuration information is carried in an RRC reconfiguration message.

37. A communication method, characterized in that: include: The first candidate node sends conditional configuration information to the source node, where the conditional configuration information is used for the terminal device to perform a layer 1 / layer 2 triggered mobility LTM process; The first candidate node is a first candidate cell; or the first candidate node is a centralized unit CU or a base station to which the first candidate cell belongs.

38. The method according to claim 37, wherein The condition configuration information is used by the terminal device to perform one or more of the following operations: Execute conditional LTM; Reporting the measurement result of the first candidate cell to the source node; Performing uplink synchronization and / or downlink synchronization with the first candidate cell in advance; Perform data forwarding; Determine the SCG processing method.

39. The method according to claim 37 or 38, characterized in that: The condition configuration information includes condition configuration information corresponding to the first candidate cell; or, The condition configuration information includes condition configuration information corresponding to a group of candidate cells.

40. The method according to claim 39, wherein: The group of candidate cells belongs to the same distribution unit DU; or, The group of candidate cells belongs to the same CU.

41. The method according to any one of claims 37 to 40, characterized in that: The first condition configuration information is included in the LTM configuration information; or, The first condition configuration information is included in the measurement configuration information of the LTM; or, The first condition configuration information is included in the configuration information of the first candidate cell.

42. The method according to any one of claims 37 to 41, characterized in that The method further comprises: The first candidate node receives a first request sent by the source node, where the first request is used to request the first candidate node to provide configuration information of the first candidate cell.

43. The method according to claim 42, characterized in that The first request includes third indication information, where the third indication information is used to indicate that the type of the LTM process is: LTM, conditional LTM, LTM between CUs, or LTM within a CU.

44. The method according to claim 42 or 43, characterized in that The first request includes a first candidate cell set, which includes the first candidate cell and other candidate cells except the first candidate cell. The first candidate cell set is used by the first candidate cell to determine conditional configuration information of the other candidate cells.

45. The method according to claim 42 or 43, characterized in that The method further comprises: After the first candidate node sends the configuration information of the first candidate cell to the source node, the first candidate node receives a second candidate cell set sent by the source node, where the second candidate cell set includes the first candidate cell and other candidate cells except the first candidate cell, and the second candidate cell set is used by the first candidate cell to determine the conditional configuration information of the other candidate cells.

46. ​​The method according to any one of claims 37 to 45, characterized in that The first candidate node is the target cell or the CU or base station to which the target cell belongs, The method further comprises: The first candidate node receives the data of the terminal device from the source node.

47. The method according to claim 46, wherein Before the first candidate node receives the data of the terminal device from the source node, the method further includes: The first candidate node sends fourth indication information to the source node, where the fourth indication information is used to instruct the source node to start sending the data of the terminal device to the target cell.

48. The method according to claim 47, wherein The fourth indication information is used to indicate that the terminal device has successfully switched to the target cell.

49. The method according to any one of claims 46 to 48, characterized in that The data of the terminal device is sent based on the Xn-U interface between the source node and the first candidate node.

50. The method according to claim 49, wherein The Xn-U interface is determined based on address information of the Xn-U interface, and the address information of the Xn-U interface is determined by the source node in the preparation stage of the LTM process.

51. The method according to any one of claims 37 to 50, characterized in that The LTM process includes one of the following: LTM process between CUs, LTM process within a CU, master cell group MCG LTM process, and SCG LTM process.

52. The method according to any one of claims 37 to 51, characterized in that The first condition configuration information is carried in an RRC reconfiguration message.

53. A terminal device, characterized in that: include: A receiving unit, configured to receive first condition configuration information from a source node; An execution unit is configured to execute a layer 1 / layer 2 triggered mobility LTM process based on the first condition configuration information.

54. The terminal device according to claim 53, characterized in that The execution unit is configured to perform one or more of the following operations based on the first condition configuration information: Execute conditional LTM; Reporting the measurement results of the candidate cells to the source node; Perform uplink synchronization and / or downlink synchronization with the candidate cell in advance; Perform data forwarding; Determine the SCG processing method.

55. The terminal device according to claim 53 or 54, characterized in that: The first condition configuration information is common configuration information applicable to all candidate cells; or, The first condition configuration information includes condition configuration information corresponding to at least one candidate cell; or, The first condition configuration information includes condition configuration information corresponding to at least one group of candidate cells.

56. The terminal device according to claim 55, characterized in that: The group of candidate cells belongs to the same distribution unit DU; or, The group of candidate cells belongs to the same CU.

57. The terminal device according to any one of claims 53 to 56, characterized in that: The first condition configuration information is generated by the source node; or, The first condition configuration information is generated by a node to which a serving cell of the terminal device belongs; or, The first condition configuration information includes condition configuration information generated by one or more candidate cells.

58. The terminal device according to any one of claims 53 to 57, characterized in that: The first condition configuration information is included in the LTM configuration information; or, The first condition configuration information is included in the measurement configuration information of the LTM; or, The first condition configuration information is included in the configuration information of the first candidate cell.

59. The terminal device according to any one of claims 53 to 58, characterized in that The execution unit is further configured to: At least one candidate cell is evaluated according to the first condition configuration information.

60. The terminal device according to claim 59, characterized in that: The at least one candidate cell is a candidate cell in the candidate cell set that has conditional configuration information; or, The at least one candidate cell is determined based on the first indication information received by the terminal device.

61. The terminal device according to claim 60, characterized in that The first indication information is carried in the switching command received by the terminal device.

62. The terminal device according to any one of claims 59 to 61, characterized in that: The at least one candidate cell includes a candidate primary cell, and the first condition configuration information includes a first condition corresponding to the candidate primary cell; and / or, The at least one candidate cell includes a candidate primary and secondary cell, and the first condition configuration information includes a second condition corresponding to the candidate primary and secondary cell.

63. The terminal device according to claim 62, characterized in that : If the candidate primary cell meets the first condition and the candidate primary and secondary cells meet the second condition, the terminal device performs the primary cell group MCG LTM process without releasing the SCG; or, If the candidate primary cell meets the first condition and the candidate primary and secondary cells do not meet the second condition, the terminal device performs the MCG LTM process and releases or retains or deactivates the SCG; or, If the candidate primary cell does not meet the first condition, and the candidate primary and secondary cells meet the second condition, the terminal device performs the SCG LTM process or does not perform cell switching; or, If the candidate primary cell satisfies the first condition and the current primary and secondary cells of the terminal device meet the third condition, the terminal device performs an MCG LTM process and keeps the SCG unchanged during the execution of the MCG LTM process; or If the candidate primary cell meets the first condition and the current primary and secondary cells of the terminal device do not meet the third condition, the terminal device executes the MCG LTM process and switches or releases the SCG during the execution of the MCG LTM process.

64. The terminal device according to any one of claims 53 to 63, characterized in that: The terminal device further includes: A sending unit is used to send second indication information to the source node, where the second indication information is used to instruct the source node to forward the data of the terminal device to the target cell.

65. The terminal device according to claim 64, characterized in that The sending unit sends the second indication information based on a fourth condition, where the fourth condition includes that at least one candidate cell satisfies a condition indicated by the condition configuration information.

66. The terminal device according to any one of claims 53 to 65, characterized in that: The LTM process is a conditional LTM process. If the first condition configuration information is used to configure the terminal device to perform conditional LTM, or the first condition configuration information is used to configure the terminal device to perform uplink synchronization and / or downlink synchronization with the candidate cell in advance, the terminal device does not report the measurement result of the candidate cell to the source node during the execution of the LTM; and / or If the first condition configuration information is used to configure the terminal device to report the measurement result of the candidate cell, the terminal device reports the measurement result of the candidate cell during the execution of the LTM process.

67. The terminal device according to claim 66, characterized in that Whether to report the measurement result of the candidate cell is determined based on protocol predefined information or indication information of the source node.

68. The terminal device according to any one of claims 53 to 67, characterized in that: The LTM process includes one of the following: an LTM process between CUs, an LTM process within a CU, an MCG LTM process, and an SCG LTM process.

69. The terminal device according to any one of claims 53 to 68, characterized in that The first condition configuration information is carried in an RRC reconfiguration message.

70. A network device, characterized in that The network device is a source node, and the network device includes: A sending unit is used to send first conditional configuration information to a terminal device, where the first conditional configuration information is used by the terminal device to perform a layer 1 / layer 2 triggered mobility LTM process; wherein the source node is a source cell; or, the source node is a centralized unit CU or a base station to which the source cell belongs.

71. The network device according to claim 70, characterized in that The first condition configuration information is used to trigger the terminal device to perform one or more of the following operations: Execute conditional LTM; Reporting the measurement results of the candidate cells to the source node; Perform uplink synchronization and / or downlink synchronization with the candidate cell in advance; Perform data forwarding; Determine the SCG processing method.

72. The network device according to claim 70 or 71, characterized in that: The first condition configuration information is common configuration information applicable to all candidate cells; or, The first condition configuration information includes condition configuration information corresponding to at least one candidate cell; or, The first condition configuration information includes condition configuration information corresponding to at least one group of candidate cells.

73. The network device according to claim 72, characterized in that: The group of candidate cells belongs to the same distribution unit DU; or, The group of candidate cells belongs to the same CU.

74. The network device according to any one of claims 70 to 73, characterized in that: The first condition configuration information is generated by the source node; or, The first condition configuration information is generated by a node to which a serving cell of the terminal device belongs; or, The first condition configuration information includes condition configuration information generated by one or more candidate cells.

75. The network device according to any one of claims 70 to 74, characterized in that: The first condition configuration information is included in the LTM configuration information; or, The first condition configuration information is included in the measurement configuration information of the LTM; or, The first condition configuration information is included in the configuration information of the first candidate cell.

76. The network device according to any one of claims 70 to 75, characterized in that The sending unit is further configured to: Sending a first request to a first candidate node, where the first request is used to request the first candidate node to provide configuration information of a first candidate cell; The first candidate node is the first candidate cell; or the first candidate node is the CU or base station to which the first candidate cell belongs.

77. The network device according to claim 76, characterized in that The first request includes third indication information, where the third indication information is used to indicate that the type of the LTM process is: LTM, conditional LTM, LTM between CUs, or LTM within a CU.

78. The network device according to claim 76 or 77, characterized in that The first request includes a first candidate cell set, which includes the first candidate cell and other candidate cells except the first candidate cell. The first candidate cell set is used by the first candidate cell to determine conditional configuration information of the other candidate cells.

79. The network device according to claim 76 or 77, characterized in that The sending unit is further configured to: After the receiving unit receives the configuration information of the first candidate cell, a second candidate cell set is sent to the first candidate node, where the second candidate cell set includes the first candidate cell and other candidate cells except the first candidate cell, and the second candidate cell set is used by the first candidate cell to determine the conditional configuration information of the other candidate cells.

80. The network device according to any one of claims 70 to 79, characterized in that The sending unit is further configured to: Send the data of the terminal device to the target cell.

81. The network device according to claim 80, wherein: The source node sends the data of the terminal device based on one or more of the following: receiving second indication information sent by the terminal device; receiving fourth indication information sent by the target cell; The measurement results reported by the terminal device; The CU corresponding to the source node receives the fifth indication information sent by the DU corresponding to the source node.

82. The network device according to claim 81, wherein: The second indication information is sent by the terminal device based on a fourth condition, and the fourth condition includes that at least one candidate cell meets the condition indicated by the condition configuration information.

83. The network device according to claim 81, characterized in that The fourth indication information is used to indicate that the terminal device has successfully switched to the target cell.

84. The network device according to claim 81, wherein: The fifth indication information is sent by the source node when receiving a switching command; or, the fifth indication information is sent by the source node based on a measurement result reported by the terminal device.

85. The network device according to any one of claims 80 to 84, characterized in that The data of the terminal device is sent based on the Xn-U interface between the source node and the target cell.

86. The network device according to claim 85, characterized in that The Xn-U interface is determined based on address information of the Xn-U interface, and the address information of the Xn-U interface is determined by the source node in the preparation stage of the LTM process.

87. The network device according to any one of claims 70 to 86, characterized in that The LTM process includes one of the following: LTM process between CUs, LTM process within a CU, master cell group MCG LTM process, and SCG LTM process.

88. The network device according to any one of claims 70 to 87, characterized in that The first condition configuration information is carried in an RRC reconfiguration message.

89. A network device, characterized in that The network device is a first candidate node, and the network device includes: a sending unit, configured to send conditional configuration information to a source node, wherein the conditional configuration information is used for a terminal device to perform a layer 1 / layer 2 triggered mobility LTM process; The first candidate node is a first candidate cell; or the first candidate node is a centralized unit CU or a base station to which the first candidate cell belongs.

90. The network device according to claim 89, wherein: The condition configuration information is used by the terminal device to perform one or more of the following operations: Execute conditional LTM; Reporting the measurement result of the first candidate cell to the source node; Performing uplink synchronization and / or downlink synchronization with the first candidate cell in advance; Perform data forwarding; Determine the SCG processing method.

91. The network device according to claim 89 or 90, characterized in that: The condition configuration information includes condition configuration information corresponding to the first candidate cell; or, The condition configuration information includes condition configuration information corresponding to a group of candidate cells.

92. The network device according to claim 91, wherein: The group of candidate cells belongs to the same distribution unit DU; or, The group of candidate cells belongs to the same CU.

93. The network device according to any one of claims 89 to 92, characterized in that: The first condition configuration information is included in the LTM configuration information; or, The first condition configuration information is included in the measurement configuration information of the LTM; or, The first condition configuration information is included in the configuration information of the first candidate cell.

94. The network device according to any one of claims 89 to 93, characterized in that The network device further includes: A receiving unit is configured to receive a first request sent by the source node, where the first request is used to request the first candidate node to provide configuration information of the first candidate cell.

95. The network device according to claim 94, characterized in that The first request includes third indication information, where the third indication information is used to indicate that the type of the LTM process is: LTM, conditional LTM, LTM between CUs, or LTM within a CU.

96. The network device according to claim 94 or 95, characterized in that The first request includes a first candidate cell set, which includes the first candidate cell and other candidate cells except the first candidate cell. The first candidate cell set is used by the first candidate cell to determine conditional configuration information of the other candidate cells.

97. The network device according to claim 94 or 95, characterized in that The receiving unit is further configured to: After the sending unit sends the configuration information of the first candidate cell to the source node, a second candidate cell set sent by the source node is received, where the second candidate cell set includes the first candidate cell and other candidate cells except the first candidate cell, and the second candidate cell set is used by the first candidate cell to determine conditional configuration information of the other candidate cells.

98. The network device according to any one of claims 89 to 97, characterized in that The first candidate node is the target cell or the CU or base station to which the target cell belongs, The receiving unit is further configured to: The data of the terminal device is received from the source node.

99. The network device according to claim 98, characterized in that Before the receiving unit receives the data of the terminal device from the source node, the sending unit is further configured to: Send fourth indication information to the source node, where the fourth indication information is used to trigger the source node to start sending data of the terminal device to the target cell.

100. The network device according to claim 99, wherein: The fourth indication information is used to indicate that the terminal device has successfully switched to the target cell.

101. The network device according to any one of claims 98 to 100, characterized in that The data of the terminal device is sent based on the Xn-U interface between the source node and the first candidate node.

102. The network device according to claim 101, wherein: The Xn-U interface is determined based on address information of the Xn-U interface, and the address information of the Xn-U interface is determined by the source node in the preparation stage of the LTM process.

103. The network device according to any one of claims 89 to 102, characterized in that The LTM process includes one of the following: LTM process between CUs, LTM process within a CU, master cell group MCG LTM process, and SCG LTM process.

104. The network device according to any one of claims 89 to 103, characterized in that The first condition configuration information is carried in an RRC reconfiguration message.

105. A terminal device, characterized in that: The terminal device comprises a memory, a processor and a communication interface, wherein the memory is used to store a program, and the processor is used to call the program in the memory so that the terminal device executes the method according to any one of claims 1 to 17.

106. A network device, characterized in that The network device comprises a memory, a processor and a communication interface, wherein the memory is used to store a program, and the processor is used to call the program in the memory so that the network device executes the method as described in any one of claims 18-36 or 37-52.

107. A device, characterized in that The device comprises a processor configured to call a program from a memory to execute the method according to any one of claims 1 to 17.

108. A device, characterized in that The device comprises a processor configured to call a program from a memory to execute the method according to any one of claims 18 to 36 or 37 to 52.

109. A chip, characterized in that: The device comprises a processor configured to call a program from a memory so that a device equipped with the chip executes the method according to any one of claims 1 to 17.

110. A chip, characterized in that: The device comprises a processor configured to call a program from a memory so that a device equipped with the chip executes the method according to any one of claims 18 to 36 or 37 to 52.

111. A computer-readable storage medium, characterized in that A program is stored thereon, the program causing a computer to execute the method according to any one of claims 1 to 17.

112. A computer-readable storage medium, characterized in that A program is stored thereon, the program causing a computer to execute the method according to any one of claims 18-36 or 37-52.

113. A computer program product, characterized in that The method comprises a program for causing a computer to execute the method according to any one of claims 1 to 17.

114. A computer program product, characterized in that The method comprises a program for causing a computer to execute the method according to any one of claims 18 to 36 or 37 to 52.

115. A computer program, characterized in that The computer program enables a computer to execute the method according to any one of claims 1 to 17.

116. A computer program, characterized in that The computer program causes a computer to execute the method according to any one of claims 18-36 or 37-52.

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