WO2020061962A1

WO2020061962A1 - Handover timing method, terminal device and network device

Info

Publication number: WO2020061962A1
Application number: PCT/CN2018/108139
Authority: WO
Inventors: 尤心
Original assignee: Oppo广东移动通信有限公司
Priority date: 2018-09-27
Filing date: 2018-09-27
Publication date: 2020-04-02
Also published as: CN112106403B; TW202025842A; CN112106403A

Abstract

Disclosed in the present invention is a handover timing method, a terminal device, a network device, a chip, a computer readable storage medium, a computer program product and a computer program, the method comprising: receiving at least one timer for at least one target network device and/or a shared timer, wherein the duration of the shared timer is at least longer than the maximum duration of the timer for the at least one target network device.

Description

Switching timing method, terminal equipment and network equipment

Technical field

The present invention relates to the field of information processing technology, and in particular, to a switching timing method, a terminal device, a network device, a chip, a computer-readable storage medium, a computer program product, and a computer program.

Background technique

In mobile communication processing, the handover may fail during the handover process. Usually the reasons for the handover failure are T304 timeout; T307 timeout; T312 timeout, etc. After the handover fails, the terminal device needs to initiate a radio resource control (RRC, Radio Resource Control) connection Re-established.

For the handover process of the terminal device, there may be a way to configure multiple target base stations for the terminal device, so that when the terminal device performs the handover, the target base station can be selected as soon as possible to ensure that the terminal device completes the handover process quickly. However, in such a processing method, how to control the connection of the terminal device is a problem to be solved.

Summary of the Invention

To solve the above technical problems, embodiments of the present invention provide a switching timing method, a terminal device, a network device, a chip, a computer-readable storage medium, a computer program product, and a computer program.

In a first aspect, an embodiment of the present invention provides a handover timing method, which is applied to a terminal device and includes:

Receive at least one timer for at least one target network device, and / or a common timer; wherein the duration of the common timer is at least greater than the maximum duration of the timer for at least one target network device.

In a second aspect, an embodiment of the present invention provides a switching timing method, which is applied to a source network device and includes:

The terminal device is configured with at least one timer for at least one target network device, and / or a common timer; wherein the duration of the common timer is at least greater than the maximum duration of the timer for at least one target network device.

According to a third aspect, an embodiment of the present invention provides a terminal device, including:

The first communication unit receives at least one timer for at least one target network device, and / or a common timer; wherein the duration of the common timer is at least greater than the maximum duration of the timer for at least one target network device.

In a fourth aspect, an embodiment of the present invention provides a source network device, including:

The second communication unit configures the terminal device with at least one timer for at least one target network device, and / or a common timer; wherein the duration of the common timer is at least longer than that of the timer for at least one target network device. Maximum duration.

In a fifth aspect, an embodiment of the present invention provides a terminal device, including a processor and a memory. The memory is used to store a computer program, and the processor is used to call and run the computer program stored in the memory, and execute the method in the above-mentioned first aspect or its implementations.

According to a sixth aspect, a network device is provided, including a processor and a memory. The memory is used to store a computer program, and the processor is used to call and run the computer program stored in the memory to execute the method in the second aspect or the implementations thereof.

In a seventh aspect, a chip is provided for implementing any one of the first to second aspects or a method in each implementation thereof.

Specifically, the chip includes a processor for invoking and running a computer program from a memory, so that a device installed with the chip executes any one of the first aspect to the second aspect described above or implementations thereof. method.

According to an eighth aspect, a computer-readable storage medium is provided for storing a computer program that causes a computer to execute the method in any one of the first to second aspects described above or in its implementations.

In a ninth aspect, a computer program product is provided, including computer program instructions that cause a computer to execute the method in any one of the first to second aspects described above or in various implementations thereof.

In a tenth aspect, a computer program is provided that, when run on a computer, causes the computer to execute the method in any one of the first to second aspects described above or in its implementations.

In the technical solution of the embodiment of the present invention, a terminal device can configure at least one timer corresponding to at least one target network device and / or a common timer during a handover stage; so that the terminal device is configured with at least one target network device. At this time, switching processing is controlled based on a corresponding timer and / or a common timer, so as to ensure processing efficiency of re-establishing a connection with a target network device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram 1 of a communication system architecture according to an embodiment of the present application; FIG.

FIG. 2 is a first schematic flowchart of a handover timing method according to an embodiment of the present application; FIG.

3 is a schematic diagram of a handover processing scenario according to an embodiment of the present invention;

4 is a second schematic flowchart of a handover timing method according to an embodiment of the present application;

5 is a schematic structural diagram of a terminal device according to an embodiment of the present application;

6 is a schematic structural diagram of a network device according to an embodiment of the present invention;

7 is a schematic structural diagram of a communication device according to an embodiment of the present invention;

FIG. 8 is a schematic block diagram of a chip according to an embodiment of the present application.

FIG. 9 is a schematic diagram 2 of a communication system architecture provided by an embodiment of the present application.

detailed description

The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, but not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative efforts shall fall within the protection scope of the present application.

The technical solutions of the embodiments of the present application can be applied to various communication systems, for example, a Global System for Mobile (GSM) system, a Code Division Multiple Access (CDMA) system, and a Wideband Code Division Multiple Access (Wideband Code Division Multiple Access) system, General Packet Radio Service (GPRS), Long Term Evolution (LTE) system, LTE Frequency Division Duplex (Freq Terminal Division Duplex, FDD) System, LTE Time Division Duplex (TDD), Universal Mobile Telecommunication System (UMTS), Global Interoperability for Microwave Access (WiMAX) communication system or 5G system, etc.

Exemplarily, the communication system 100 applied in the embodiment of the present application may be shown in FIG. 1. The communication system 100 may include a network device 110, and the network device 110 may be a device that communicates with a terminal device 120 (or a communication terminal or a terminal). The network device 110 may provide communication coverage for a specific geographic area, and may communicate with terminal devices located within the coverage area. Optionally, the network device 110 may be a network device (Base Transceiver Station, BTS) in a GSM system or a CDMA system, or a network device (NodeB, NB) in a WCDMA system, or may be an evolution in an LTE system. Type network equipment (Evolutional NodeB, eNB or eNodeB), or a wireless controller in a Cloud Radio Access Network (CRAN), or the network equipment may be a mobile switching center, relay station, access point, Vehicle-mounted devices, wearable devices, hubs, switches, bridges, routers, network-side devices in 5G networks, or network devices in public land mobile networks (PLMN) that will evolve in the future.

The communication system 100 further includes at least one terminal device 120 located within a coverage area of the network device 110. As the "terminal equipment" used herein includes, but is not limited to, connection via wired lines, such as via Public Switched Telephone Networks (PSTN), Digital Subscriber Line (DSL), digital cable, direct cable connection ; And / or another data connection / network; and / or via a wireless interface, such as for cellular networks, Wireless Local Area Networks (WLAN), digital television networks such as DVB-H networks, satellite networks, AM- FM broadcast transmitter; and / or another terminal device configured to receive / transmit communication signals; and / or Internet of Things (IoT) devices. A terminal device configured to communicate through a wireless interface may be referred to as a “wireless communication terminal”, a “wireless terminal”, or a “mobile terminal”. Examples of mobile terminals include, but are not limited to, satellite or cellular phones; personal communications systems (PCS) terminals that can combine cellular radiotelephones with data processing, facsimile, and data communications capabilities; can include radiotelephones, pagers, Internet / internal PDA with network access, web browser, notepad, calendar, and / or Global Positioning System (GPS) receiver; and conventional laptop and / or palm-type receivers or others including radiotelephone transceivers Electronic device. A terminal device can refer to an access terminal, user equipment (terminal equipment), user unit, user station, mobile station, mobile station, remote station, remote terminal, mobile device, user terminal, terminal, wireless communication device, user agent Or user device. The access terminal can be a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Processing (PDA), and wireless communication. Functional handheld devices, computing devices or other processing devices connected to wireless modems, vehicle-mounted devices, wearable devices, terminal devices in 5G networks, or terminal devices in future evolved PLMNs, etc.

Optionally, terminal devices 120 may perform terminal direct device (D2D) communication.

Optionally, the 5G system or the 5G network may also be referred to as a New Radio (NR) system or an NR network.

FIG. 1 exemplarily shows one network device and two terminal devices. Optionally, the communication system 100 may include multiple network devices and the coverage of each network device may include other numbers of terminal devices. The embodiment does not limit this.

Optionally, the communication system 100 may further include other network entities such as a network controller, a mobility management entity, and the like in this embodiment of the present application is not limited thereto.

It should be understood that the device having a communication function in the network / system in the embodiments of the present application may be referred to as a communication device. Taking the communication system 100 shown in FIG. 1 as an example, the communication device may include a network device 110 and a terminal device 120 having a communication function, and the network device 110 and the terminal device 120 may be specific devices described above, and are not described herein again The communication device may also include other devices in the communication system 100, such as other network entities such as a network controller, a mobile management entity, and the like, which is not limited in the embodiments of the present application.

It should be understood that the terms "system" and "network" are often used interchangeably herein. The term "and / or" in this document is only an association relationship describing related objects, which means that there can be three kinds of relationships, for example, A and / or B can mean: A exists alone, A and B exist simultaneously, and they exist alone B these three cases. In addition, the character "/" in this article generally indicates that the related objects are an "or" relationship.

In order to understand the features and technical contents of the embodiments of the present invention in more detail, the implementation of the embodiments of the present invention will be described in detail below with reference to the accompanying drawings. The accompanying drawings are for reference only and are not intended to limit the embodiments of the present invention.

Example one,

An embodiment of the present invention provides a switching timing method, which is applied to a terminal device. As shown in FIG. 2, the method includes:

Step 201: Receive at least one timer for at least one target network device, and / or a common timer;

Wherein, among the at least one timer corresponding to the at least one target network device, the timing duration of different timers may be the same or different;

In addition, the timing duration of the common timer may be greater than the timing duration of the timer with the largest timing duration among all the timers; or the timing duration of the common timer may also be the sum of the timing durations of all the timers; of course The timing duration of the common timer may also be greater than the sum of the timing durations of all the timers. The duration of at least one timer and the common timer can be set according to the actual situation, and it is not exhaustive here.

Further, after receiving at least one timer and / or a common timer, the solution provided in this embodiment may further include: when initiating a connection to a target network device, based on the at least one timer, and / or, The common timer does the processing.

The receiving at least one timer for at least one target network device and / or a common timer includes:

Receive a handover command, and obtain at least one timer for at least one target network device and / or a common timer through the handover command.

At least one timer of at least one target network device of the terminal device, and / or, a common timer corresponding to at least one target network device may be directly configured by the source network device, or the target network device may also pass the source network device. Forwarded to the terminal device.

Refer to Figure 3 for the processing flow of handover, including:

The handover preparation phase includes steps 1-6 in the figure: the source network device sends measurement control to the terminal device; after the terminal device performs measurements for multiple network devices or cells, it sends a measurement report to the source network device; the source network device according to the measurement report (Or combined with RRM information) to make a handover decision; the source network device sends a handover request to the target network device to prepare the target network device for handover; the target network device performs handover admission control based on the handover request; when the target network device determines to perform handover, The network device sends a handover request confirmation.

Then perform the handover phase, which includes steps 7-11 in the figure. Specifically: the target network device generates RRC information, sends the RRC connection reconfiguration information to the source network device, and the source network device sends the RRC connection reconfiguration information to the terminal device. ; After receiving the RRC connection reconfiguration information, the terminal device performs handover processing according to the connection reconfiguration information; then the source network device sends the SN status to the target network device; the terminal device synchronizes with the target network device, and then receives the target network device for UL Allocate and send RRC connection reconfiguration completion information to the target network device.

Finally, it enters the handover completion stage, including 12-18 in the figure. Specifically: the target network device sends a path switching request to the MME to notify the MME terminal device to change the cell; the MME sends a bearer adjustment request to the serving gateway, and the MME performs the downlink path switching process. After the serving gateway finishes processing, it sends a bearer adjustment completion process to the MME, and the MME sends a confirmation message of the path switching request to the target network device; the target network device notifies the source network device of the terminal device context release and the source network device releases the resources.

In combination with this embodiment, when the terminal device has a target network device, the source network device may directly send a timer through a switch command, or send a timer through a reconfiguration message forwarded, that is, a timing for the target network device. When the terminal device has at least two target network devices, the source network device can directly configure at least two timers and / or public timers by switching instructions, or it can configure the terminal devices by forwarding reconfiguration messages At least two timers, and / or, common timers.

A message may be sent to a terminal device for a timer and / or a common timer corresponding to each target network device; or, a timer and / Or the common timer is added to the same message, and then only one message is sent to the terminal device.

It should be understood that, in addition to the foregoing timers and / or common timers, the reconfiguration message may also include: mobile control information, new C-RNTI, and security information of the second target network device; in addition, optional It also includes information such as the random access preamble, the system information block (SIB) of the second target network device.

Specifically, this embodiment can be applied to the following multiple scenarios:

Scenario 1: A terminal device may have at least two target network devices, and all target network devices correspond to a common timer.

It should be understood that, in this scenario, timers can be sent for at least two target network devices, that is, timers for at least two target network devices are sent separately, and each timer can be a common timer; or It is also possible to send only one common timer and configure that the common timer can be applied to all target network devices.

In this scenario, the common timer may be obtained through a switching command, or the common timer may be obtained from a reconfiguration message that is forwarded.

The initiating a connection to a target network device based on the at least one timer and / or a common timer includes:

When a handover command is received, a common timer is started to initiate a connection to the first target network device.

Alternatively, the initiating a connection to a target network device based on the at least one timer and / or a common timer further includes:

If the received handover command (HO command) carries a reconfiguration message containing at least two target network devices, a common timer may be started when the terminal device selects the first target network device to be currently accessed.

In this scenario, you can also use the same common timer for multiple network devices, and provide the following sub-scenarios:

Sub-scene one,

Every time the connection to the target network device fails and the second target network device is connected, the public timer is restarted, specifically:

If the connection is successfully initiated to the first target network device within the duration of the timer, the common timer is stopped.

If the common timer times out and / or the connection with the first target network device fails, it is determined that the terminal device fails to switch to the first target network device.

When it is determined that the handover of the terminal device to the first target network device fails, the method further includes:

When the connection to the first target network device fails, or when the common timer stops and the first target network device fails to connect, determine the second target network device, restart the common timer, and initiate to the second target network device connection.

The method for determining a second target network device may include one of the following:

Re-accept the handover command sent by the source network device, and obtain the second target network device based on the handover command; wherein the handover command includes the second target network device reselected by the network side for the terminal device.

Alternatively, if the reconfiguration message received by the terminal device carries information of at least two target network devices, a second target network device is selected from the at least two target network devices.

The method for selecting a second target network device from the at least two target network devices may be selecting a second target network device from the at least two target network devices randomly, or based on the at least two target network devices. Select the priority to select the second target network device.

The selection priority may be a parameter set by the network side for different target network devices according to the actual situation; the network side may set different selection priorities for different target network devices by referring to the measurement report of the terminal device. For example, the higher the signal measurement quality in the measurement report, the higher the selection priority that can be set; otherwise, the selection priority angle can be set; and / or, based on the physical distance of the target network device, the distance from the current source can be set. The network device with a shorter physical distance has a higher priority (or lower priority); of course, there can be other settings in actual processing, and this embodiment does not exhaustively.

It should be understood that, when performing the handover processing for the second target network device, the processing method for the first target network device may be used for processing, but details are not described herein again.

When the common timer expires, it is confirmed that the handover fails, and the connection with the source network device is returned, or connection reestablishment is initiated. Specifically, when the first target network device or the second target network device fails to switch, both can return to the connection to the source network device or initiate connection reestablishment to the new target network device. Among them, the new target network device is different from the target network device that failed in this handover.

It should also be understood that when the connection is re-initiated to the second target network device, the second target network device can be used as a new first target network device for subsequent operations, that is, when the new first target network device When the device is successfully connected, it can be determined that the handover is successful. If the connection of the new first target network device fails, the new second target network device is re-selected again, and the process is performed in a loop.

When the second target network device is determined, a common timer is restarted, and a connection is initiated to the second target network device, the method further includes:

Judging whether the number of restarts of the common timer exceeds a preset number of times threshold; if the number of times of restarting the common timer exceeds a preset number of times, it confirms that the handover fails, returns to the connection with the source network device, or initiates connection reestablishment; The value can be set according to actual conditions. For example, you can restart the public timer more than 5 times to confirm that there is no suitable target network device for the current switchover, so that the switchover fails. Of course, it can also be determined according to the number of target network devices. Preset number threshold, for example, the preset number threshold can be 2/3 of the number of target network devices. Assuming that there are 9 target network devices, the public timer can be restarted 6 times; in addition, there may be other The method for setting the preset number of times threshold is only exhaustive in this embodiment.

or,

It is determined whether the number of times of reselecting the target network device exceeds a preset selection threshold. If the number of times of reselecting the target network device exceeds the preset selection threshold, it is confirmed that the handover fails, and the connection with the source network device is returned, or connection reestablishment is initiated. The preset selection threshold may be set according to the actual situation. For example, it may be determined that there is no suitable target network device for the current switchover to reselect the target network device more than 3 times, thereby determining the switchover failure; of course. You can also determine the threshold for the preset number of times based on the number of target network devices. For example, the preset selection threshold can be 2/3 of the number of target network devices. Assuming that there are 9 target network devices, you can reselect them. The target network device determines that the handover has failed more than 6 times; in addition, there may be other methods for setting the threshold value for the preset number of times, but in this embodiment, no exhaustion is performed.

Sub-scene two,

Multiple network devices share a common timer, and each time the connection to the target network device fails, the target network device is directly reselected until the common timer stops. specific:

When the connection to the first target network device fails and the common timer does not expire, selecting a second target network device from at least one target network device to initiate a connection to the second target network device;

or,

When the connection of the first target network device fails and the common timer does not expire, the second target network device configured in the handover command is acquired, and a connection is initiated to the second target network device.

In the process of reselecting the second target network device from at least one network device each time, it is not necessary to maintain a connection with the source network device; and each time the switch command is reacquired, the second target network device based on the configuration of the switch command is re- In the process of initiating the connection, the connection to the source network device may be returned every time the connection fails.

It should be noted that after the connection is initiated to the second target network device, the second target network device can be used as the first target network device again, and the operations in this scenario can be continued. Furthermore, when the new first target network device fails to connect When re-selecting a new second target network device again, the process is cyclically performed until the public timer stops, and when the target network device that can be connected is still not selected, it can be confirmed that the handover fails and returns to the source network device. Connect, or, initiate connection re-establishment.

Scene two,

The terminal device has at least two target network devices, and each target network device corresponds to a timer.

It should be understood that in this scenario, at least two timers for at least two target network devices configured by the receiving source network device; among which, the timers corresponding to different target network devices may have the same or different timer durations. It is determined by each target network device, which is not limited in this embodiment.

In this scenario, the source network device may directly send a timer to the terminal device in a handover command; or, the source network device may forward the reconfiguration message of at least two target network devices to the terminal device.

When a handover command is received, a first timer for the first target network device is started, and a connection is initiated to the first target network device.

Further, if the connection is successfully initiated to the first target network device within the time length of the first timer, the first timer is stopped.

If the first timer times out and / or the connection with the first target network device fails, it is determined that the terminal device fails to switch to the first target network device.

When the connection of the first target network device fails, selecting a second target network device from at least one target network device to initiate a connection, and starting a timer of the second target network device;

or,

When the connection of the first target network device fails, the second target network device configured in the handover command is acquired, a connection is initiated to the second target network device, and a timer of the second target network device is started.

The method for selecting a second target network device from the at least two target network devices may be selecting a second target network device from at least two target network devices randomly, or based on the at least two target network devices. Select the priority to select the second target network device.

It should also be noted that in this scenario, when the second target network device is selected to initiate the connection, the second target network device selected this time may be used as the new first target network device. Accordingly, the second timer is used as the new first target network device. The first timer of the switch performs connection control; that is, when the new first target network device does not connect successfully when the first timer expires, a new second target network device is selected again and the new The second timer corresponding to the second target network device is processed cyclically.

Further, the above-mentioned loop processing may be ended by judging whether the number of times of reselecting a new target network device exceeds a preset selection threshold, and if exceeding, determining that the handover fails; or, it may also be judged to restart a new Whether the number of timers of the timer exceeds a preset threshold, and if it exceeds the threshold, it is determined that the handover fails. For the method of determining the preset selection threshold and the preset number of times, refer to the description in the scenario 1, which is not repeated here.

When the timer expires, it is confirmed that the handover fails, and the connection with the source network device is returned, or connection re-establishment is initiated. Specifically, the first target network device or the second target network device can use the above description to determine whether the handover is successful; and when the handover fails, they can return to the source network device or re-connect to the new The second target network device initiates connection reconstruction. Wherein, the new second target network device is different from the second target network device that failed in the handover.

Scene three,

The terminal device is provided with at least two target network devices, each target network device corresponds to a timer, and all target network devices share a common timer. It should be understood that the timing duration of the timers corresponding to different target network devices may be the same or different; the timing duration of the common timer may be greater than the timing duration of the timer with the largest timing duration among all timers; or, The timing duration of the common timer may also be the sum of the timing durations of all the timers; of course, the timing duration of the common timer may be greater than the sum of the timing durations of all the timers. The duration of at least one timer and the common timer can be set according to the actual situation, and it is not exhaustive here.

In this scenario, at least two timers corresponding to the at least two target network devices can be obtained from the reconfiguration message forwarded by the source base station; or the source network device directly sets at least two timers in the handover command to send to the terminal device. .

When a handover command is received, a first timer of a first target network device is started, and a common timer is started to initiate a connection to the first target network device.

Further, if the connection is successfully initiated to the first target network device within the time length of the first timer, the first timer is stopped. If the first timer times out and / or the connection with the first target network device fails, it is determined that the terminal device fails to switch to the first target network device.

After the initiating the connection to the first target network device, the method further includes:

When the first timer of the first target network device stops and / or the connection to the first target network device fails, if the common timer has not timed out, the second target network device is selected from at least one target network device and sent to the second The target network device initiates a connection and starts a timer of the second target network device;

or,

When the first timer of the first target network device stops and / or the connection to the first target network device fails, if the common timer has not expired, the second target network device is acquired based on the handover command, and initiated to the second target network device Connect and start the timer of the second target network device.

Further, the above-mentioned loop processing may be ended in a manner that, when the common timer expires, it is confirmed that the handover fails, and the connection with the source network device is returned, or connection reestablishment is initiated.

It should also be noted that, when it is determined that the handover fails and returns to the connection to the source network device, or when the connection is initiated to the target network device, the terminal device in this embodiment may also retain the connection with the source network device; Wherein, the terminal device retains the first protocol stack and the first related key with the source network device, and maintains the second protocol stack and the second related key with the first target network device;

The first related key is different from the second related key. The second correlation key may be generated from the first correlation key.

The first protocol stack and the second protocol stack may be the same or different, or at least partially different. For example, when targeting a 5G system, it may be a terminal device and a source network device, and a terminal device and a first target network device. Maintain different service data application protocols (SDAP, Service Data Adaptation Protocol), different packet data convergence protocols (PDCP, Packet Data Convergence Protocol), different radio link layer control protocols (RLC, Radio Link Control), different Media access control (MAC) entities, different low-layer entities; when targeting 4G systems, different packet data aggregations can be maintained for terminal equipment and source network equipment, and between terminal equipment and first target network equipment Protocol (PDCP, Packet Data Convergence Protocol), different radio link layer control protocols (RLC, Radio Link Control), different media access control (MAC) entities, different low layer (Low layer) entities. In addition, in the solution provided by this embodiment, in order to ensure that different keys are used, the PDCP of the first protocol stack and the second protocol stack must be different. At least one of SDAP, RLC, MAC, and physical layer may be the same or different. Alternatively, the first protocol stack and the second protocol stack may share at least one of SDAP, RLC, MAC, and physical layer, or may have SDAP, RLC, MAC, and physical layer, respectively.

The first target network device and the second target network device in this embodiment are target network devices when the terminal device is switched; or, the first target network device and the second target network device are auxiliary nodes SN, and the The source network device is the master node MN. It should be noted here that in the long-term evolution (LTE) system, the SN is called SCG, and the new radio (NR) is SN, which refers to the same concept, that is, the second service network device in the DC scenario. The applicable scenarios of this embodiment are: the terminal maintains a connection with the source network device and fails to connect to the target network device; the terminal source network device disconnects and successfully connects with the target network device; the auxiliary cell group (SCG) connection fails, and the SCG changes Connection failed. Of course, it may also be that in a scenario where multiple SCGs are configured, one SCG connection fails; in a scenario where multiple target cells are configured, one target cell connection fails. There may also be other applicable scenarios, but in this embodiment, exhaustion is no longer performed.

It can be seen that, by using the foregoing solution, at least one timer and / or common timer corresponding to at least one target network device can be configured; so that when the terminal device is configured with at least one target network device, based on the corresponding timer and / Or the common timer controls the switching process, thereby ensuring the processing efficiency of re-establishing a connection with the target network device.

Example two,

An embodiment of the present invention provides a handover timing method, which is applied to a source network device, as shown in FIG. 4, and includes:

Step 401: Configure the terminal device with at least one timer for at least one target network device, and / or a common timer; wherein the duration of the common timer is at least greater than the maximum duration of the timer for at least one target network device. .

The configuring the terminal device with at least one timer for at least one target network device and / or a common timer includes:

The handover command carries at least one timer for at least one target network device, and / or a common timer, and sends the handover command to the terminal device.

At least one timer of at least one target network device of the terminal device may be configured by the source network device directly through a switch command, or may be forwarded by the target network device to the terminal device through the source network device.

Refer to Figure 3 for the processing flow of handover, including:

In combination with this embodiment, when the terminal device has a target network device, the source network device can send a timer directly through a switch command, or send a timer by forwarding a reconfiguration message, that is, a timer for the target network device. ; When the terminal device has at least two target network devices, the source network device can configure at least two timers and / or public timers directly by switching instructions, or can configure the terminal device by forwarding reconfiguration messages At least two timers, and / or, common timers.

The method further includes: selecting a target network device based on a measurement report corresponding to at least one network device; or randomly selecting a target network device from the at least one network device.

Wherein, selecting the target network device can select at least one target network device for the terminal device when the source network device receives the measurement report of at least one network device from the terminal device; and then pass the relevant information of the at least one target network device through A reconfiguration message or a switch command is sent to the terminal device; it should be noted that when sending at least one target network device, at least one timer corresponding to the at least one target network device and / or a common timer need to be added.

And / or, selecting the target network device, when the terminal device fails to connect to the first target network device, the source network device selects the second target network device for the terminal device from the at least one target network device, and selects the target network device. The second target network device is sent to the terminal device through a reconfiguration message or a handover command. It should be noted that when sending the second target network device, a second timer corresponding to the second target network device needs to be added.

Example three,

An embodiment of the present invention provides a terminal device, as shown in FIG. 5, including:

The first communication unit 51 receives at least one timer for at least one target network device, and / or a common timer; wherein the duration of the common timer is at least greater than the maximum duration of the timer for at least one target network device Initiating a connection to a target network device based on the at least one timer and / or a common timer.

The first communication unit 51,

Receiving a reconfiguration message of a target network device forwarded by a source network device, and acquiring at least one timer for at least one target network device and / or a common timer carried in the reconfiguration message;

or,

Receive a handover command from a source network device, and obtain at least one timer for at least one target network device and / or a common timer through the handover command.

That is, at least one timer of at least one target network device of the terminal device, and / or, a common timer corresponding to at least one target network device may be directly configured by the source network device, or may also be passed by the target network device. It is forwarded by the source network device to the terminal device.

Refer to Figure 3 for the processing flow of handover, including:

In combination with this embodiment, when the terminal device has a target network device, the source network device can send a timer directly through a switch command, or send a timer by forwarding a reconfiguration message, that is, a timer for the target network device. ; When the terminal device has at least two target network devices, the source network device can directly configure the terminal device with at least two timers and / or public timers by switching instructions, or it can forward the reconfiguration message to the terminal. The device is configured with at least two timers, and / or a common timer.

The terminal device further includes:

The first processing unit 52 starts a common timer when receiving a handover command, and initiates a connection to the first target network device through the first communication unit 51.

The first processing unit 52, if the received handover command (HO command) carries a reconfiguration message including at least two target network devices, when the terminal device selects the first target network device to be currently accessed, Start the common timer.

Sub-scene one,

The first processing unit 52 stops the common timer if the connection is successfully initiated to the first target network device within the duration of the timer.

When it is determined that the handover of the terminal device to the first target network device fails, the first processing unit 52, when the connection to the first target network device fails, or when the common timer stops and the first target network device fails to connect To determine a second target network device, restart the common timer, and initiate a connection to the second target network device through the first communication unit 51.

The first processing unit 52 reaccepts the handover command sent by the source network device, and obtains the second target network device based on the handover command. The handover command includes the second target network device reselected by the network side for the terminal device.

The method for selecting a second target network device from the at least two target network devices may be the first processing unit 52, randomly selecting the second target network device from the at least two target network devices, or based on A selection priority of at least two target network devices selects a second target network device.

When the second target network device is determined, a common timer is restarted, and when a connection is initiated to the second target network device, the first processing unit 52 determines whether the number of restarts of the common timer exceeds a preset number of times If the threshold value is exceeded, it is confirmed that the handover fails, and the connection with the source network device is returned, or connection reestablishment is initiated; wherein the preset number of times may be set according to actual conditions, for example, it may be restarted If the public timer exceeds 5 times, it is confirmed that there is no suitable target network device for handover at present, so that the handover fails. Of course, a preset number of times can be determined according to the number of target network devices, for example, the preset number of times It can be 2/3 of the number of target network devices. Assuming that there are 9 target network devices, the public timer can be restarted 6 times. In addition, there can be other methods for setting the threshold of preset times, but this implementation No more exhaustive in the example.

or,

The first processing unit 52 determines whether the number of times of re-selecting the target network device exceeds a preset selection threshold. If the number of times of re-selection of the target network device exceeds the preset selection threshold, it confirms that the handover fails, returns to the connection with the source network device, or initiates connection reconstruction. The preset selection threshold may be set according to the actual situation. For example, it may be determined that there is no suitable target network device for the current switchover to reselect the target network device more than 3 times, thereby determining the switchover failure; of course. You can also determine the threshold for the preset number of times based on the number of target network devices. For example, the preset selection threshold can be 2/3 of the number of target network devices. Assuming that there are 9 target network devices, you can reselect them. The target network device determines that the handover has failed more than 6 times; in addition, there may be other methods for setting the threshold value for the preset number of times, but in this embodiment, no exhaustion is performed.

Sub-scene two,

The first processing unit 52 selects a second target network device from at least one target network device when the connection to the first target network device fails and the common timer does not expire, and sends the second target network device to the second target through the first communication unit 51 A network device initiates a connection;

or,

When the connection of the first target network device fails and the common timer does not expire, the second target network device configured in the handover command is acquired, and a connection is initiated to the second target network device through the first communication unit 51.

Scene two,

The first processing unit 52, when receiving the handover command, starts a first timer for the first target network device, and initiates a connection to the first target network device through the first communication unit 51.

When it is determined that the handover of the terminal device to the first target network device fails, the first processing unit 52,

or,

Further, the manner of ending the above-mentioned cyclic processing may be that the first processing unit 52 determines whether the number of times of reselecting a new target network device exceeds a preset selection threshold, and if it exceeds, determines that the handover fails; or It can be judged whether the number of times of restarting the new timer exceeds a preset number of times threshold, and if it exceeds, it is determined that the handover fails. For the method of determining the preset selection threshold and the preset number of times, refer to the description in the scenario 1, which is not repeated here.

Scene three,

When receiving the handover command, the first processing unit 52 starts a first timer of the first target network device and starts a common timer, and initiates a connection to the first target network device through the first communication unit 51.

After the initiating the connection to the first target network device, the first processing unit 52,

or,

Embodiment 4

An embodiment of the present invention provides a source network device, as shown in FIG. 6, including:

The second communication unit 61 configures the terminal device with at least one timer for at least one target network device, and / or a common timer; wherein the duration of the common timer is at least longer than the timer for at least one target network device Maximum duration.

The second communication unit 61 carries at least one timer for at least one target network device and / or a common timer in the handover command, and sends the handover command to the terminal device.

Specifically, at least one timer of at least one target network device of the terminal device may be configured by the source network device directly through a switch command, or may be forwarded by the target network device to the terminal device through the source network device.

Refer to Figure 3 for the processing flow of handover, including:

In combination with this embodiment, when the terminal device has a target network device, the source network device can send a timer directly through a switch command, or send a timer by forwarding a reconfiguration message, that is, a timer for the target network device. ; When the terminal device has at least two target network devices, the source network device can directly configure at least two timers and / or public timers by switching instructions, or can configure the terminal device at least by forwarding reconfiguration messages Two timers, and / or, a common timer.

The source network device further includes:

The second processing unit 62 selects the target network device based on the measurement report corresponding to the at least one network device; or randomly selects the target network device from the at least one network device.

FIG. 7 is a schematic structural diagram of a communication device 700 according to an embodiment of the present application. The communication device may be the terminal device or the network device described in this embodiment. The communication device 700 shown in FIG. 7 includes a processor 710, and the processor 710 may call and run a computer program from a memory to implement the method in the embodiment of the present application.

Optionally, as shown in FIG. 7, the communication device 700 may further include a memory 720. The processor 710 may call and run a computer program from the memory 720 to implement the method in the embodiment of the present application.

The memory 720 may be a separate device independent of the processor 710, or may be integrated in the processor 710.

Optionally, as shown in FIG. 7, the communication device 700 may further include a transceiver 730, and the processor 710 may control the transceiver 730 to communicate with other devices. Specifically, it may send information or data to other devices, or receive other information. Information or data sent by the device.

The transceiver 730 may include a transmitter and a receiver. The transceiver 730 may further include antennas, and the number of antennas may be one or more.

Optionally, the communication device 700 may specifically be a network device according to an embodiment of the present application, and the communication device 700 may implement a corresponding process implemented by a network device in each method of the embodiments of the present application. For brevity, details are not described herein again. .

Optionally, the communication device 700 may specifically be a terminal device or a network device in the embodiment of the present application, and the communication device 700 may implement the corresponding process implemented by the mobile terminal / terminal device in each method in the embodiments of the present application. Concise, I won't repeat them here.

FIG. 8 is a schematic structural diagram of a chip according to an embodiment of the present application. The chip 800 shown in FIG. 8 includes a processor 810, and the processor 810 can call and run a computer program from a memory to implement the method in the embodiment of the present application.

Optionally, as shown in FIG. 8, the chip 800 may further include a memory 820. The processor 810 may call and run a computer program from the memory 820 to implement the method in the embodiment of the present application.

The memory 820 may be a separate device independent of the processor 810, or may be integrated in the processor 810.

Optionally, the chip 800 may further include an input interface 830. The processor 810 may control the input interface 830 to communicate with other devices or chips. Specifically, the processor 810 may obtain information or data sent by other devices or chips.

Optionally, the chip 800 may further include an output interface 840. The processor 810 may control the output interface 840 to communicate with other devices or chips. Specifically, the processor 810 may output information or data to the other devices or chips.

Optionally, the chip may be applied to the network device in the embodiment of the present application, and the chip may implement the corresponding process implemented by the network device in each method of the embodiment of the present application. For brevity, details are not described herein again.

Optionally, the chip may be applied to the terminal device in the embodiment of the present application, and the chip may implement the corresponding process implemented by the terminal device in each method of the embodiment of the present application. For brevity, details are not described herein again.

It should be understood that the chip mentioned in the embodiments of the present application may also be referred to as a system-level chip, a system chip, a chip system or a system-on-chip.

FIG. 9 is a schematic block diagram of a communication system 900 according to an embodiment of the present application. As shown in FIG. 9, the communication system 900 includes a terminal device 910 and a network device 920.

The terminal device 910 may be used to implement the corresponding functions implemented by the terminal device in the foregoing method, and the network device 920 may be used to implement the corresponding functions implemented by the network device in the foregoing method. For brevity, details are not described herein again. .

It should be understood that the processor in the embodiment of the present application may be an integrated circuit chip and has a signal processing capability. In the implementation process, each step of the foregoing method embodiment may be completed by using an integrated logic circuit of hardware in a processor or an instruction in a form of software. The above processor may be a general-purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), an off-the-shelf programmable gate array (Field, Programmable Gate Array, FPGA), or other Programming logic devices, discrete gate or transistor logic devices, discrete hardware components. Various methods, steps, and logical block diagrams disclosed in the embodiments of the present application can be implemented or executed. A general-purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in combination with the embodiments of the present application may be directly implemented by a hardware decoding processor, or may be performed by using a combination of hardware and software modules in the decoding processor. The software module may be located in a mature storage medium such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory, or an electrically erasable programmable memory, a register, and the like. The storage medium is located in a memory, and the processor reads the information in the memory and completes the steps of the foregoing method in combination with its hardware.

It can be understood that the memory in the embodiment of the present application may be a volatile memory or a non-volatile memory, or may include both volatile and non-volatile memory. Among them, the non-volatile memory may be a read-only memory (ROM), a programmable read-only memory (PROM), an erasable programmable read-only memory (EPROM), and an electronic memory. Erase programmable read-only memory (EPROM, EEPROM) or flash memory. The volatile memory may be Random Access Memory (RAM), which is used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), Synchronous Dynamic Random Access Memory (Synchronous DRAM, SDRAM), double data rate synchronous dynamic random access memory (Double SDRAM, DDR SDRAM), enhanced synchronous dynamic random access memory (Enhanced SDRAM, ESDRAM), synchronous connection dynamic random access memory (Synchlink DRAM, SLDRAM ) And direct memory bus random access memory (Direct Rambus RAM, DR RAM). It should be noted that the memory of the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

It should be understood that the foregoing memory is exemplary but not restrictive. For example, the memory in the embodiment of the present application may also be a static random access memory (static RAM, SRAM), a dynamic random access memory (dynamic RAM, DRAM), Synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (Double SDRAM, DDR SDRAM), enhanced synchronous dynamic random access memory (enhanced SDRAM, ESDRAM), synchronous connection Dynamic random access memory (synch link DRAM, SLDRAM) and direct memory bus random access memory (Direct RAMbus RAM, DR RAM) and so on. That is, the memories in the embodiments of the present application are intended to include, but not limited to, these and any other suitable types of memories.

An embodiment of the present application further provides a computer-readable storage medium for storing a computer program.

Optionally, the computer-readable storage medium can be applied to the network device in the embodiment of the present application, and the computer program causes the computer to execute the corresponding process implemented by the network device in each method in the embodiment of the present application. No longer.

Optionally, the computer-readable storage medium can be applied to the terminal device in the embodiment of the present application, and the computer program causes the computer to execute the corresponding process implemented by the mobile terminal / terminal device in each method of the embodiment of the present application, for the sake of brevity , Will not repeat them here.

An embodiment of the present application further provides a computer program product, including computer program instructions.

Optionally, the computer program product can be applied to the network device in the embodiment of the present application, and the computer program instruction causes the computer to execute a corresponding process implemented by the network device in each method in the embodiment of the present application. More details.

Optionally, the computer program product can be applied to a mobile terminal / terminal device in the embodiments of the present application, and the computer program instructions cause the computer to execute a corresponding process implemented by the mobile terminal / terminal device in each method in the embodiments of the present application, For brevity, I will not repeat them here.

The embodiment of the present application also provides a computer program.

Optionally, the computer program may be applied to a network device in the embodiment of the present application. When the computer program is run on a computer, the computer is caused to execute a corresponding process implemented by the network device in each method in the embodiment of the present application. , Will not repeat them here.

Optionally, the computer program may be applied to a mobile terminal / terminal device in the embodiment of the present application. When the computer program is run on a computer, the computer executes each method in the embodiment of the application by the mobile terminal / terminal device. The corresponding processes are not repeated here for brevity.

Those of ordinary skill in the art may realize that the units and algorithm steps of each example described in connection with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional technicians can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices, and units described above can refer to the corresponding processes in the foregoing method embodiments, and are not repeated here.

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

The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, may be located in one place, or may be distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the objective of the solution of this embodiment.

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

If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application is essentially a part that contributes to the existing technology or a part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including Several instructions are used to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in the embodiments of the present application. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (Read-Only Memory) ROM, random access memory (Random Access Memory, RAM), magnetic disks or optical disks and other media that can store program codes .

The above is only a specific implementation of this application, but the scope of protection of this application is not limited to this. Any person skilled in the art can easily think of changes or replacements within the technical scope disclosed in this application. It should be covered by the protection scope of this application. Therefore, the protection scope of this application shall be subject to the protection scope of the claims.

Claims

A switching timing method applied to a terminal device includes:

Receiving at least one timer for at least one target network device, and / or a common timer;

The duration of the common timer is at least greater than the maximum duration of a timer for at least one target network device.
The method according to claim 1, wherein said receiving at least one timer for at least one target network device and / or a common timer comprises:

Receive a handover command, and obtain at least one timer for at least one target network device and / or a common timer through the handover command.
The method according to claim 1 or 2, wherein after receiving at least one timer for at least one target network device, and / or after a common timer, the method further comprises:

When a handover command is received, a common timer is started to initiate a connection to the first target network device.
The method according to claim 3, wherein after the initiating a connection to the first target network device, the method further comprises:

When the connection to the first target network device fails, or when the common timer stops and the first target network device fails to connect, determine the second target network device, restart the common timer, and initiate to the second target network device connection.
The method according to claim 4, wherein when determining the second target network device, restarting a common timer, and initiating a connection to the second target network device, the method further comprises:

Judging whether the number of restarting the public timer exceeds a preset number of times threshold; if it exceeds, confirming that the handover fails, returning to the connection with the source network device, or initiating connection reestablishment;

or,

It is determined whether the number of times of reselecting the target network device exceeds a preset selection threshold. If the number of times of reselecting the target network device exceeds the preset selection threshold, it is confirmed that the handover fails, and the connection with the source network device is returned, or connection reestablishment is initiated.
The method according to claim 3, wherein after the initiating a connection to the first target network device, the method further comprises:

When the connection to the first target network device fails and the common timer does not expire, selecting a second target network device from at least one target network device to initiate a connection to the second target network device;

or,

When the connection of the first target network device fails and the common timer does not expire, the second target network device configured in the handover command is acquired, and a connection is initiated to the second target network device.
The method according to claim 6, wherein the method further comprises:

When the common timer expires, it is confirmed that the handover fails, and the connection with the source network device is returned, or connection reestablishment is initiated.
The method according to claim 1 or 2, wherein after receiving at least one timer for at least one target network device, and / or after a common timer, the method further comprises:

When a handover command is received, a first timer for the first target network device is started, and a connection is initiated to the first target network device.
The method according to claim 8, wherein after the initiating a connection to the first target network device, the method further comprises:

When the first target network device fails to connect, selecting a second target network device from at least one target network device to initiate a connection, and starting a second timer of the second target network device;

or,

When the connection of the first target network device fails, the second target network device configured in the handover command is acquired, a connection is initiated to the second target network device, and a second timer of the second target network device is started.
The method according to claim 1 or 2, wherein after receiving at least one timer for at least one target network device, and / or after a common timer, the method further comprises:

When a handover command is received, a first timer of a first target network device is started, and a common timer is started to initiate a connection to the first target network device.
The method according to claim 10, wherein after the initiating a connection to the first target network device, the method further comprises:

When the first timer of the first target network device stops and / or the connection to the first target network device fails, if the common timer has not timed out, the second target network device is selected from at least one target network device and sent to the second The target network device initiates a connection and starts a timer of the second target network device;

or,

When the first timer of the first target network device stops and / or the connection to the first target network device fails, if the common timer has not expired, the second target network device is acquired based on the handover command, and initiated to the second target network device Connect and start the timer of the second target network device.
The method according to claim 11, wherein the method further comprises:

When the common timer expires, it is confirmed that the handover fails, and the connection with the source network device is returned, or connection reestablishment is initiated.
The method according to any one of claims 1-12, wherein:

The first target network device and the second target network device are target network devices when the terminal device is switched;

or,

The first target network device and the second target network device are auxiliary nodes SN, and the source network device is a master node MN.
A switching timing method applied to a source network device includes:

The terminal device is configured with at least one timer for at least one target network device, and / or a common timer; wherein the duration of the common timer is at least greater than the maximum duration of the timer for at least one target network device.
The method according to claim 14, wherein the configuring the terminal device with at least one timer for at least one target network device and / or a common timer comprises:

The handover command carries at least one timer for at least one target network device, and / or a common timer, and sends the handover command to the terminal device.
The method according to claim 14, wherein the method further comprises:

Selecting a target network device based on a measurement report corresponding to at least one network device;

Alternatively, a target network device is randomly selected from the at least one network device.
The method according to any one of claims 14-16, wherein:

The first target network device and the second target network device are target network devices when the terminal device is switched;

or,

The first target network device and the second target network device are auxiliary nodes SN, and the source network device is a master node MN.
A terminal device includes:

The first communication unit receives at least one timer for at least one target network device, and / or a common timer; wherein the duration of the common timer is at least greater than the maximum duration of the timer for at least one target network device.
The terminal device according to claim 18, wherein the first communication unit,

Receive a handover command, and obtain at least one timer for at least one target network device and / or a common timer through the handover command.
The terminal device according to claim 18 or 19, wherein the terminal device further comprises:

The first processing unit, when receiving the handover command, starts a common timer and initiates a connection to the first target network device through the first communication unit.
The terminal device according to claim 20, wherein the first processing unit determines a second when a connection to the first target network device fails or when a common timer stops and the first target network device fails to connect. The target network device restarts the common timer, and initiates a connection to the second target network device through the first communication unit.
The terminal device according to claim 21, wherein the first processing unit,

Judging whether the number of restarting the public timer exceeds a preset number of times threshold; if it exceeds, confirming that the handover fails, returning to the connection with the source network device, or initiating connection reestablishment;

or,

It is determined whether the number of times of reselecting the target network device exceeds a preset selection threshold. If the number of times of reselecting the target network device exceeds the preset selection threshold, it is confirmed that the handover fails, and the connection with the source network device is returned, or connection reestablishment is initiated.
The terminal device according to claim 20, wherein the first processing unit,

When the connection to the first target network device fails and the common timer does not expire, selecting a second target network device from at least one target network device, and initiating a connection to the second target network device through the first communication unit;

or,

When the connection of the first target network device fails and the common timer does not expire, the second target network device configured in the handover command is acquired, and a connection is initiated to the second target network device through the first communication unit.
The terminal device according to claim 23, wherein the first processing unit, when the common timer expires, confirms that the handover fails, and returns the connection with the source network device through the first communication unit, or initiates connection reestablishment.
The terminal device according to claim 18 or 19, wherein the terminal device further comprises:

The first processing unit, when receiving the handover command, starts a first timer for the first target network device, and initiates a connection to the first target network device through the first communication unit.
The terminal device according to claim 25, wherein the first processing unit selects a second target network device from at least one target network device to initiate a connection when the first target network device fails to connect, and starts the first target network device. A second timer of two target network devices;

or,

When the connection of the first target network device fails, the second target network device configured in the handover command is acquired, a connection is initiated to the second target network device, and a second timer of the second target network device is started.
The terminal device according to claim 18 or 19, wherein the terminal device further comprises:

The first processing unit, when receiving the handover command, starts a first timer of the first target network device and starts a common timer, and initiates a connection to the first target network device through the first communication unit.
The terminal device according to claim 27, wherein the first processing unit,

When the first timer of the first target network device stops and / or the connection to the first target network device fails, if the common timer has not timed out, the second target network device is selected from at least one target network device and sent to the second The target network device initiates a connection and starts a timer of the second target network device;

or,

When the first timer of the first target network device stops and / or the connection to the first target network device fails, if the common timer has not expired, the second target network device is acquired based on the handover command, and initiated to the second target network device Connect and start the timer of the second target network device.
The terminal device according to claim 28, wherein the first processing unit, when the common timer expires, confirms that the handover fails, and controls to return the connection with the source network device through the first communication unit, or initiate connection reestablishment .
The terminal device according to any one of claims 18-29, wherein:

The first target network device and the second target network device are target network devices when the terminal device is switched;

or,

The first target network device and the second target network device are auxiliary nodes SN, and the source network device is a master node MN.
A source network device includes:

The second communication unit configures the terminal device with at least one timer for at least one target network device, and / or a common timer; wherein the duration of the common timer is at least longer than that of the timer for at least one target network device. Maximum duration.
The source network device according to claim 31, wherein the second communication unit is

The handover command carries at least one timer for at least one target network device, and / or a common timer, and sends the handover command to the terminal device.
The source network device according to claim 31, wherein the source network device further comprises:

A second processing unit, selecting a target network device based on a measurement report corresponding to at least one network device;

Alternatively, a target network device is randomly selected from the at least one network device.
The source network device according to any one of claims 31-33, wherein:

The first target network device and the second target network device are target network devices when the terminal device is switched;

or,

The first target network device and the second target network device are auxiliary nodes SN, and the source network device is a master node MN.
A terminal device includes a processor and a memory for storing a computer program capable of running on the processor,

The memory is used to store a computer program, and the processor is used to call and run the computer program stored in the memory, and execute the steps of the method according to any one of claims 1-13.
A network device including a processor and a memory for storing a computer program capable of running on the processor,

The memory is used to store a computer program, and the processor is used to call and run the computer program stored in the memory, and execute the steps of the method according to any one of claims 14-17.
A chip includes a processor for calling and running a computer program from a memory, so that a device having the chip installed executes the method according to any one of claims 1-13.
A chip includes: a processor for calling and running a computer program from a memory, so that a device having the chip installed executes the method according to any one of claims 14-17.
A computer-readable storage medium for storing a computer program, the computer program causing a computer to perform the steps of the method according to any one of claims 1-17.
A computer program product includes computer program instructions that cause a computer to perform the method according to any one of claims 1-17.
A computer program that causes a computer to perform the method according to any one of claims 1-17.