CN114339925A

CN114339925A - Switching method, device, terminal equipment, network equipment and storage medium

Info

Publication number: CN114339925A
Application number: CN202011080570.8A
Authority: CN
Inventors: 赵亚利
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2020-10-10
Filing date: 2020-10-10
Publication date: 2022-04-12
Anticipated expiration: 2040-10-10
Also published as: WO2022073491A1; CN114339925B

Abstract

The embodiment of the application provides a switching method, a switching device, a terminal device, a network device and a storage medium, wherein the switching method comprises the following steps: sending a Radio Resource Control (RRC) connection establishment request message to a target cell; the RRC connection establishment request message carries first indication information, and the first indication information is used for assisting the target cell in determining a source cell of terminal equipment (UE); wherein the UE is connected with at least one of the target cell and the source cell through a relay. For the scene that the terminal equipment UE performs switching by itself, the embodiment of the application can ensure the service continuity during switching.

Description

Switching method, device, terminal equipment, network equipment and storage medium

Technical Field

The present application relates to the field of communications technologies, and in particular, to a handover method, apparatus, terminal device, network device, and storage medium.

Background

With conventional communication networks, handover decisions are made by network devices. However, after the relay is introduced, since when to perform relay selection may depend on a terminal Equipment (UE) implementation, it is highly likely that the handover is initiated by the UE itself after the relay is introduced. When the handover is initiated by the UE, the service continuity during the handover cannot be guaranteed.

Disclosure of Invention

Embodiments of the present application provide a handover method, an apparatus, a terminal device, a network device, and a storage medium, so as to solve a problem in the prior art that service continuity cannot be guaranteed when a terminal device UE performs handover by itself.

In order to solve the above problem, in particular, the embodiment of the present application provides the following technical solutions:

in a first aspect, an embodiment of the present application provides a handover method, including:

sending a Radio Resource Control (RRC) connection establishment request message to a target cell; the RRC connection establishment request message carries first indication information, and the first indication information is used for assisting the target cell in determining a source cell of terminal equipment (UE);

wherein the UE is connected with at least one of the target cell and the source cell through a relay.

Optionally, the first indication information includes any one or more of the following information:

identification information of the UE;

source cell identification information of the UE.

Optionally, the identification information of the UE includes any one of:

the UE is in a cell radio network temporary identifier C-RNTI of a source cell;

5G-S-TMSI of the UE;

a part of information of 5G-S-TMSI of the UE.

Optionally, the source cell identity information of the UE includes any one of:

a Cell Global Identity (CGI) of a source cell of the UE;

a combination of a public land mobile network, PLMN, and a cell identity of a source cell of the UE;

the frequency point of the UE source cell and the physical cell identification PCI;

PCI of the UE source cell.

Optionally, the handover method further includes:

and receiving an RRC reconfiguration message sent by the target cell, wherein the RRC reconfiguration message is generated according to the UE context information acquired from the source cell of the UE after the target cell sends a first request message for requesting the UE context information to the source cell of the UE after receiving the RRC connection establishment request message.

Optionally, the handover method further includes:

and receiving an RRC reconfiguration message sent by the source cell, wherein the RRC reconfiguration message is generated according to the UE context information acquired from the source cell of the UE and sent to the source cell through an interface between base stations after the target cell sends a first request message for requesting the UE context information to the source cell of the UE after receiving the RRC connection establishment request message.

Optionally, the handover method further includes:

sending an RRC reconfiguration complete message to the target cell so that the target cell sends second indication information to a source cell of the UE and sends third indication information to a core network; the second indication information is used for indicating a source cell of the UE to perform data forwarding; and the third indication information is used for requesting the core network to carry out route switching.

Optionally, the method further comprises: judging switching;

when the direct connection and the indirect connection need to be switched, the judgment condition corresponding to the judgment of switching comprises any one or more of the following conditions:

the channel quality of a direct communication interface between the terminal equipment and the target relay in the indirect connection is higher than a first threshold;

the channel quality of a target relay Uu interface in the indirect connection is higher than a second threshold;

the quality of a Uu interface channel between the terminal equipment and the source cell is lower than a third threshold;

the number of times of hybrid automatic repeat request (HARQ) Negative Acknowledgements (NACKs) continuously transmitted by a Uu interface between the terminal equipment and the source cell is higher than a fourth threshold;

a radio link failure RLF occurs at a Uu interface between the terminal equipment and a source cell;

the direct connection is the connection established between the terminal equipment and the network equipment directly through a Uu interface; the indirect connection refers to connection established by the terminal equipment through the relay equipment and the network.

Optionally, the method further comprises: judging switching;

when the switching of indirect connection to direct connection is required, the judgment condition corresponding to the judgment of switching includes any one or more of the following conditions:

the channel quality of a direct communication interface between the terminal equipment and the source relay is lower than a fifth threshold;

the channel quality of the source relay Uu interface is lower than a sixth threshold;

the quality of a Uu interface channel between the terminal equipment and the target cell is higher than a seventh threshold;

the terminal equipment receives fourth indication information sent by a source relay, wherein the fourth indication information is used for indicating to release relay connection;

the number of times of the continuous hybrid automatic repeat request (HARQ) Negative Acknowledgement (NACK) of a direct communication interface between the terminal equipment and the source relay is higher than an eighth threshold;

the number of the continuous HARQ NACK times of the source relay Uu interface is higher than a ninth threshold;

a Radio Link Failure (RLF) occurs at a direct communication interface between the terminal equipment and the source relay;

RLF occurs at a source relay Uu interface;

Optionally, the method further comprises: judging switching;

when the first indirect connection and the second indirect connection need to be switched, the judgment condition corresponding to the judgment of switching comprises any one or more of the following conditions:

the channel quality of a direct communication interface between the terminal equipment and the source relay is lower than a tenth threshold;

the channel quality of the Uu interface of the source relay is lower than an eleventh threshold;

the channel quality of a direct communication interface between the terminal equipment and the target relay is higher than a twelfth threshold;

the channel quality of the Uu interface of the target relay is higher than a thirteenth threshold;

the terminal equipment receives fifth indication information sent by a source relay, wherein the fifth indication information is used for indicating the release of relay connection;

the number of times of the continuous hybrid automatic repeat request (HARQ) Negative Acknowledgement (NACK) of a direct communication interface between the terminal equipment and the source relay is higher than a fourteenth threshold;

the number of times of the source relay Uu interface continuous HARQ NACK is higher than a fifteenth threshold;

RLF occurs at a source relay Uu interface;

the indirect connection refers to connection established by the terminal equipment through the relay equipment and the network.

In a second aspect, an embodiment of the present application provides a handover method, including:

receiving a Radio Resource Control (RRC) connection establishment request message sent by terminal equipment (UE); the RRC connection establishment request message carries first indication information, and the first indication information is used for assisting a target cell to determine a source cell of the UE;

identification information of the UE;

source cell identification information of the UE.

Optionally, the identification information of the UE includes any one of:

the UE is in a cell radio network temporary identifier C-RNTI of a source cell;

5G-S-TMSI of the UE;

a part of information of 5G-S-TMSI of the UE.

Optionally, the source cell identity information of the UE includes any one of:

a Cell Global Identity (CGI) of a source cell of the UE;

PCI of the UE source cell.

Optionally, the handover method further includes:

sending a first request message for requesting context information of the UE to a source cell of the UE;

generating an RRC reconfiguration message according to the context information of the UE acquired from the source cell of the UE; and sending the RRC reconfiguration message to the UE.

Optionally, the handover method further includes:

generating an RRC reconfiguration message according to the context information of the UE acquired from the source cell of the UE;

and sending the RRC reconfiguration message to a source cell of the UE through an interface between base stations.

Optionally, the handover method further includes:

receiving an RRC reconfiguration completion message sent by the UE, and sending second indication information to a source cell of the UE and third indication information to a core network; the second indication information is used for indicating a source cell of the UE to perform data forwarding; and the third indication information is used for requesting the core network to carry out route switching.

Optionally, after sending the second indication information to the source cell of the UE and sending the third indication information to the core network, the method further includes:

sending sixth indication information to a source cell of the UE; the sixth indication information is used for indicating the source cell of the UE to release the context information of the UE.

In a third aspect, an embodiment of the present application provides a switching device, including:

a sending module, configured to send a radio resource control RRC connection establishment request message to a target cell; the RRC connection establishment request message carries first indication information, and the first indication information is used for assisting the target cell in determining a source cell of terminal equipment (UE);

In a fourth aspect, an embodiment of the present application provides a switching device, including:

a receiving module, configured to receive a radio resource control RRC connection establishment request message sent by a terminal device UE; the RRC connection establishment request message carries first indication information, and the first indication information is used for assisting a target cell to determine a source cell of the UE;

In a fifth aspect, an embodiment of the present application provides a terminal device, including a memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor implements the following steps when executing the computer program:

identification information of the UE;

source cell identification information of the UE.

Optionally, the identification information of the UE includes any one of:

the UE is in a cell radio network temporary identifier C-RNTI of a source cell;

5G-S-TMSI of the UE;

a part of information of 5G-S-TMSI of the UE.

Optionally, the source cell identity information of the UE includes any one of:

a Cell Global Identity (CGI) of a source cell of the UE;

PCI of the UE source cell.

Optionally, the processor, when executing the computer program, is further configured to implement the following steps:

Optionally, the processor is further configured to perform a handover determination when executing the computer program;

RLF occurs at a source relay Uu interface;

In a sixth aspect, an embodiment of the present application provides a target cell-side network device, including a memory, a processor, and a computer program stored on the memory and executable on the processor, where the processor implements the following steps when executing the computer program:

identification information of the UE;

source cell identification information of the UE.

Optionally, the identification information of the UE includes any one of:

the UE is in a cell radio network temporary identifier C-RNTI of a source cell;

5G-S-TMSI of the UE;

a part of information of 5G-S-TMSI of the UE.

Optionally, the source cell identity information of the UE includes any one of:

a Cell Global Identity (CGI) of a source cell of the UE;

PCI of the UE source cell.

and sending the RRC reconfiguration message to the UE.

after sending second indication information to a source cell of the UE and sending third indication information to a core network, sending sixth indication information to the source cell of the UE; the sixth indication information is used for indicating the source cell of the UE to release the context information of the UE.

In a seventh aspect, this application embodiment further provides a processor-readable storage medium, where the processor-readable storage medium stores a computer program, where the computer program is configured to cause the processor to execute the steps of the handover method according to the first aspect or the second aspect.

According to the handover method, the handover device, the terminal device, the network device and the storage medium provided by the embodiments of the present application, when the terminal device UE needs to establish a connection with at least one of the target cell and the source cell through a relay, when the radio resource control RRC connection establishment request message is sent to the target cell, the RRC connection establishment request message carries first indication information for assisting the target cell in determining the source cell of the UE, so that the target cell can determine the source cell of the UE through the first indication information carried in the RRC connection establishment request message, and thus when the UE performs handover by itself, the target cell can be ensured to acquire the source cell information, thereby ensuring the continuity of a service, and further solving the problem that the continuity of the service cannot be ensured when the UE performs handover by itself in the prior art.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative efforts.

Fig. 1 is a schematic communication manner of network centralized control provided by an embodiment of the present application;

fig. 2 is a schematic diagram of direct communication interface discovery/communication provided by an embodiment of the present application;

fig. 3 is a schematic diagram of a UE-to-Network Relay provided in an embodiment of the present application;

fig. 4 is a flowchart illustrating steps of a handover method applied to a terminal device according to an embodiment of the present application;

fig. 5 is a flowchart illustrating steps of a handover method applied to a target cell-side network device according to an embodiment of the present application;

fig. 6 is a schematic flow chart of a handover method according to an embodiment of the present application;

fig. 7 is a second flowchart of a handover method according to an embodiment of the present application;

fig. 8 is a third schematic flowchart of a handover method according to an embodiment of the present application;

fig. 9 is a block diagram of a switching device applied to a terminal device according to an embodiment of the present application;

fig. 10 is a block diagram of a handover apparatus applied to a target cell-side network device according to an embodiment of the present application;

fig. 11 is a schematic structural diagram of a terminal device provided in an embodiment of the present application;

fig. 12 is a schematic structural diagram of a target cell-side network device according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The conventional communication systems mainly include two types, namely, a cellular network communication system and a direct communication system. As shown in fig. 1, a cellular network communication mode is generally adopted in conventional wireless communication, that is, a terminal and a network side device transmit uplink and downlink data/control information through a Uu interface. As shown in fig. 2, the direct communication method is a method in which a neighboring terminal can perform data transmission via a direct communication link (also referred to as Sidelink) in a short distance. The wireless interface to which the Sidelink link corresponds is called the direct communication interface (also called the Sidelink interface or PC5 interface)

To extend network coverage, one of the more common solutions is to introduce relays (relays). Relay may be a terminal with Relay function. The situations of introducing the Relay are divided into two types, one is UE-to-Network Relay, and the other is UE-to-UE Relay.

For a UE-to-Network Relay, see fig. 3, the interface between the Relay and the Network uses the Uu interface, and the interface between the relayed UE (which may also be referred to as a far-end UE) uses a direct communication interface. The link between the Relay and the network may be referred to as a Backhaul link (BH) for the remote UE.

For UE-to-UE Relay, two relayed UEs may transmit data through the Relay device. For simplicity of description, a connection of a UE accessing a network through a relay is also referred to as an indiect connection (also referred to as an indirect connection); a connection where the UE accesses the network directly over the Uu interface is also called a direct connection (also called a direct connection).

It is understood that an indiect (indirect) connection is a UE accessing the network through a relay; direct is the UE connecting directly to the network over the Uu interface.

It should be noted that, the bearers in the relay scene are divided into three categories:

the direct communication interface bears: i.e. the bearer between the remote UE and the relay UE;

end-to-end bearing between the remote UE and the network equipment: namely end-to-end bearing established between a remote end and network equipment;

bearing of the remote UE on a return link of the Uu interface: i.e. the bearer between the relay UE and the network device for carrying the data of the remote UE.

Regardless of the type of bearer, the bearer and the logical channel are in one-to-one correspondence, and the logical channel has a corresponding logical channel identifier.

As described in the background section, with conventional communication networks, handover decisions are performed by network devices. However, after the relay is introduced, since when to perform relay selection may be implemented by a terminal device (UE), after the relay is introduced, handover (such as handover between direct/index or index/direct or index/index) may be initiated by the UE itself. When the handover is initiated by the UE, the service continuity during the handover cannot be guaranteed. In order to solve the problem, an embodiment of the present application provides a handover method, an apparatus, a terminal device, a network device, and a storage medium, and a core idea of the embodiment of the present application is: if the UE performs handover decision between direct and index links or between different index links by itself, the UE needs to carry first indication information in an RRC connection establishment request message sent to the target network device, where the first indication information is used to assist the target network device in determining a source cell of the UE, so that the target cell may determine the source cell of the UE through the first indication information carried in the RRC connection establishment request message, and thus when the UE performs handover by itself, it may be ensured that the target cell may acquire the source cell information, thereby ensuring continuity of a service, and further solving a problem in the prior art that service continuity cannot be ensured when the UE performs handover by itself. The following explains and explains the handover method, apparatus, terminal device, network device and storage medium provided by the present application in detail by using specific embodiments.

It should be noted that, in the following description, since the method and the apparatus are based on the same application concept, and the principles of solving the problems of the method and the apparatus are similar, the implementation of the apparatus and the method can be mutually referred, and repeated details are not repeated.

In addition, it should be noted that the technical solutions provided in the embodiments of the present application may be applied to various systems, especially 5G systems. For example, the applicable system may be a global system for mobile communication (GSM) system, a Code Division Multiple Access (CDMA) system, a Wideband Code Division Multiple Access (WCDMA) General Packet Radio Service (GPRS) system, a long term evolution (long term evolution, LTE) system, an LTE Frequency Division Duplex (FDD) system, an LTE Time Division Duplex (TDD) system, an LTE-a (long term evolution) system, a universal mobile system (universal mobile telecommunications system, UMTS), a Worldwide Interoperability for Mobile Access (WiMAX) system, a New Radio network (NR 5) system, etc. These various systems include terminal devices and network devices. The System may further include a core network portion, such as an Evolved Packet System (EPS), a 5G System (5GS), and the like.

The terminal device referred to in the embodiments of the present application may refer to a device providing voice and/or data connectivity to a user, a handheld device having a wireless connection function, or another processing device connected to a wireless modem. In different systems, the names of the terminal devices may be different, for example, in a 5G system, the terminal device may be called a User Equipment (UE). A wireless terminal device, which may be a mobile terminal device such as a mobile telephone (or "cellular" telephone) and a computer having a mobile terminal device, for example, a portable, pocket, hand-held, computer-included, or vehicle-mounted mobile device, may communicate with one or more Core Networks (CNs) via a Radio Access Network (RAN). Examples of such devices include Personal Communication Service (PCS) phones, cordless phones, Session Initiation Protocol (SIP) phones, Wireless Local Loop (WLL) stations, and Personal Digital Assistants (PDAs). The wireless terminal device may also be referred to as a system, a subscriber unit (subscriber unit), a subscriber station (subscriber station), a mobile station (mobile), a remote station (remote station), an access point (access point), a remote terminal device (remote terminal), an access terminal device (access terminal), a user terminal device (user terminal), a user agent (user agent), and a user device (user device), which are not limited in this embodiment of the present application. Since the terminal device forms a network capable of supporting communication with other network devices (e.g., a core network device, an access network device (i.e., a base station)), the terminal device is also considered as a network device in the present invention.

The network device related to the embodiment of the present application may be a base station, where the base station may include multiple cells providing services for a terminal, and may also be a CU (Central Unit) or a DU (Distributed Unit). A network device may also be referred to as an access point or a device in an access network that communicates over the air-interface, through one or more sectors, with wireless terminal devices, or by other names, depending on the particular application. The network device may be configured to exchange received air frames with Internet Protocol (IP) packets as a router between the wireless terminal device and the rest of the access network, which may include an Internet Protocol (IP) communication network. The network device may also coordinate attribute management for the air interface. For example, the network device according to the embodiment of the present application may be a Base Transceiver Station (BTS) in a Global System for Mobile communications (GSM) or a Code Division Multiple Access (CDMA), may be a network device (NodeB) in a Wideband Code Division Multiple Access (WCDMA), may be an evolved Node B (eNB or e-NodeB) in a Long Term Evolution (LTE) System, may be a 5G Base Station (gbb) in a 5G network architecture (next evolution System), may be a Home evolved Node B (HeNB), a relay Node (relay Node), a Home Base Station (femto), a pico Base Station (pico Base Station), and the like, which are not limited in the embodiments of the present application. In some network architectures, a network device may include a Centralized Unit (CU) node and a Distributed Unit (DU) node, which may also be geographically separated.

Furthermore, it should be understood that the term "and/or" in the embodiments of the present application describes an association relationship of associated objects, and means that there may be three relationships, for example, a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship.

Reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present application. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

The present application is explained in detail below.

As shown in fig. 4, a flowchart of steps of a handover method applied to a terminal device according to an embodiment of the present application is provided, where the method includes the following steps:

step 101: sending a Radio Resource Control (RRC) connection establishment request message to a target cell; the RRC connection establishment request message carries first indication information, and the first indication information is used for assisting the target cell in determining a source cell of terminal equipment (UE);

In this embodiment, in order to ensure the continuity of the service when the UE performs handover by itself, the following technical means is adopted in this embodiment: when a Radio Resource Control (RRC) (radio Resource control) connection establishment request message is sent to a target cell, first indication information for assisting the target cell to determine a source cell of the UE is carried in the RRC connection establishment request message, so that the target cell can determine the source cell of the UE through the first indication information carried in the RRC connection establishment request message, and service continuity can be ensured.

In this embodiment, since the first indication information is indication information for assisting the target cell in determining the source cell of the UE, in an optional implementation, the content of the first indication information may include at least one or more of the following information: identification information of the UE; ② source cell identification information of the UE. For example, in an implementation manner, the first indication information may only include source cell identification information of the UE, and the target cell may determine the source cell of the UE according to the source cell identification information of the UE; in another implementation, the first indication information may include the identification information of the UE and the identification information of the source cell of the UE at the same time, and the target cell may determine the source cell of the UE according to the source cell identification of the UE and may determine which UE is in the source cell at the same time.

In this embodiment, the identification information of the UE may be, but is not limited to, one of the following: firstly, a Cell radio network temporary identifier (C-RNTI) of the UE in a source Cell; ② the 5G-S-TMSI or a part of the 5G-S-TMSI of the UE.

In this embodiment, the source cell identity of the UE may be, but is not limited to, one of the following: cell Global identity cgi (Cell Global identity) of a source Cell of the UE may include, for example, (PLMN ID + Cell ID); frequency points of the UE source Cell and a physical Cell identifier PCI (physical Cell ID); and thirdly, PCI of the UE source cell.

According to the handover method provided by the embodiment of the application, when the UE needs to establish connection with at least one of the target cell and the source cell through the relay, when the RRC connection establishment request message is sent to the target cell, the first indication information for assisting the target cell in determining the source cell of the UE is carried in the RRC connection establishment request message, so that the target cell can determine the source cell of the UE through the first indication information carried in the RRC connection establishment request message, when the UE performs handover by itself, the target cell can be ensured to acquire the source cell information, service continuity can be ensured, and the problem that service continuity cannot be ensured when the UE performs handover by itself in the prior art is solved.

Based on the content of the foregoing embodiments, in this embodiment, the first indication information includes any one or more of the following information:

identification information of the UE;

source cell identification information of the UE.

In this embodiment, it should be noted that, in an implementation manner, the first indication information may include identification information of the UE; in another implementation, the first indication information may include source cell identification information of the UE; in yet another implementation, the first indication information may include identification information of the UE and source cell identification information of the UE.

Based on the content of the foregoing embodiment, in this embodiment, the identification information of the UE includes any one of the following items:

the UE is in a cell radio network temporary identifier C-RNTI of a source cell;

5G-S-TMSI of the UE;

a part of information of 5G-S-TMSI of the UE.

In this embodiment, it should be noted that the identification information of the UE is used to uniquely identify the UE, so as to form a distinction with other UEs. In one implementation, the identity information of the UE may include a cell radio network temporary identity C-RNTI of the UE in a source cell; in another implementation, the identity information of the UE may include a 5G-S-TMSI of the UE; in yet another implementation, the identity information of the UE may include a portion of the 5G-S-TMSI information of the UE. It is understood that the identification information of the UE may include a part of the 5G-S-TMSI of the UE, meaning that the identification information of the UE may include a part of the 5G-S-TMSI that can be used to accurately identify the UE, for example, including the 5G-TMSI identification part in the 5G-S-TMSI of the UE.

Based on the content of the foregoing embodiment, in this embodiment, the source cell identification information of the UE includes any one of the following items:

a Cell Global Identity (CGI) of a source cell of the UE;

PCI of the UE source cell.

In this embodiment, the source cell identification information of the UE is used to uniquely identify the source cell of the UE, so as to form a distinction with other cells. In one implementation, the source cell identity information of the UE may include a Cell Global Identity (CGI) of a source cell of the UE; in another implementation, the UE includes a combination of a public Land Mobile network plmn (public Land Mobile network) and a Cell Identity of a source Cell; in another implementation manner, the source cell identifier information of the UE may include a frequency point of the source cell of the UE plus a physical cell identifier PCI; in yet another implementation, the source cell identification information of the UE may include a PCI of the UE source cell.

Based on the content of the foregoing embodiment, in this embodiment, the switching method further includes:

In this embodiment, it should be noted that, after receiving the first indication information, the target cell may perform the following processing: and the target cell generates an RRC reconfiguration message according to the context of the UE acquired from the source cell and sends the RRC reconfiguration message to the UE.

In this embodiment, different from the above embodiment, the embodiment is to receive an RRC reconfiguration message sent by a source cell, where the RRC reconfiguration message is generated according to context information of UE acquired from the source cell of the UE and sent to the source cell through an inter-base station interface after the target cell sends a first request message for requesting context information of the UE to the source cell of the UE after receiving the RRC connection establishment request message.

In this embodiment, it should be noted that, after receiving the RRC reconfiguration complete message sent by the UE, the target cell may further perform the following operations: and after receiving an RRC reconfiguration complete message sent by the UE, sending third indication information to the core network, wherein the third indication information is used for requesting a core network route switching request (Path switch request) to request route switching.

In this embodiment, the notifying the source cell to perform data forwarding refers to notifying the source cell to send data locally stored in the source cell to the target cell after the handover is completed.

Based on the content of the foregoing embodiment, in this embodiment, before sending the RRC connection establishment request message to the target cell, the handover method further includes: judging switching;

In the present embodiment, it is understood that the switching of the direct connection to the indirect connection may be performed as long as one or more of the following conditions are satisfied: firstly, the channel quality of a direct communication interface between terminal equipment and a target relay in indirect connection is higher than a first threshold; secondly, the channel quality of the target relay Uu interface in indirect connection is higher than a second threshold; the quality of a Uu interface channel between the terminal equipment and the source cell is lower than a third threshold; fourthly, the times of continuous hybrid Automatic Repeat request (HARQ) of a Uu interface between the terminal equipment and the source cell (hybrid Automatic Repeat request) Negative Acknowledgement (NACK) are higher than a fourth threshold; radio Link Failure (RLF) occurs at a Uu interface between the terminal equipment and the source cell.

It should be noted that the values of the first threshold, the second threshold, the third threshold, and the fourth threshold may be set according to actual needs, which is not limited in this embodiment.

Based on the content of the foregoing embodiment, in this embodiment, before sending the RRC connection establishment request message to the target cell, the method further includes: judging switching;

RLF occurs at a source relay Uu interface;

In the present embodiment, it is understood that the handover of the indirect connection to the direct connection may be performed as long as one or more of the following conditions are satisfied: the channel quality of a direct communication interface between the terminal equipment and the source relay is lower than a fifth threshold; the channel quality of the source relay Uu interface is lower than a sixth threshold; the quality of a Uu interface channel between the terminal equipment and the target cell is higher than a seventh threshold; receiving fourth indication information sent by the source relay by the terminal equipment, wherein the fourth indication information is used for indicating to release the relay connection; the number of times of the HARQ Negative Acknowledgement (NACK) of the continuous hybrid automatic repeat request (HARQ) between the terminal equipment and the source relay is higher than an eighth threshold; sixthly, the number of the continuous HARQ NACK times of the source relay Uu interface is higher than a ninth threshold; generating Radio Link Failure (RLF) on a direct communication interface between the terminal equipment and the source relay; and generating RLF at the source relay Uu interface.

It should be noted that values of the fifth threshold, the sixth threshold, the seventh threshold, the eighth threshold, and the ninth threshold may be set according to actual needs, which is not limited in this embodiment.

RLF occurs at a source relay Uu interface;

In the present embodiment, it is understood that the switching of the first indirect connection to the second indirect connection may be performed as long as one or more of the following conditions are satisfied: the channel quality of a direct communication interface between the terminal equipment and the source relay is lower than a tenth threshold; the channel quality of a source relay Uu interface is lower than an eleventh threshold; the channel quality of a direct communication interface between the terminal equipment and the target relay is higher than a twelfth threshold; fourthly, the channel quality of the Uu interface of the target relay is higher than a thirteenth threshold; the terminal equipment receives fifth indication information sent by the source relay, wherein the fifth indication information is used for indicating the release of relay connection; sixthly, the times of the HARQ Negative Acknowledgement (NACK) of the continuous hybrid automatic repeat request of the direct communication interface between the terminal equipment and the source relay are higher than a fourteenth threshold; seventhly, the number of the source relay Uu interface continuous HARQ NACK is higher than a fifteenth threshold; allowing a direct communication interface between the terminal equipment and the source relay to generate Radio Link Failure (RLF); and ninthly, RLF occurs at the Uu interface of the source relay.

It should be noted that values of the tenth threshold, the eleventh threshold, the twelfth threshold, the thirteenth threshold, the fourteenth threshold, and the fifteenth threshold may be set according to actual needs, and this embodiment does not limit this.

As shown in fig. 5, a flowchart of steps of a handover method applied to a target cell network device side according to an embodiment of the present application is provided, where the method includes the following steps:

step 201: receiving a Radio Resource Control (RRC) connection establishment request message sent by terminal equipment (UE); the RRC connection establishment request message carries first indication information, and the first indication information is used for assisting a target cell to determine a source cell of the UE;

According to the switching method provided by the embodiment of the application, when the UE and at least one of the target cell and the source cell need to establish connection through the relay, the service continuity during switching can be ensured by receiving the Radio Resource Control (RRC) connection establishment request message which is sent by the UE and carries the first indication information. This is because: the first indication information is indication information for assisting the target cell in determining the source cell of the UE, so that the target cell can determine the source cell of the terminal device UE through the first indication information carried in the RRC connection establishment request message, and thus when the UE performs handover by itself, the target cell can be ensured to acquire the source cell information, so that service continuity can be ensured, and the problem that service continuity cannot be ensured in the prior art when the UE performs handover by itself is solved.

identification information of the UE;

source cell identification information of the UE.

the UE is in a cell radio network temporary identifier C-RNTI of a source cell;

5G-S-TMSI of the UE;

a part of information of 5G-S-TMSI of the UE.

In this embodiment, it should be noted that the identification information of the UE is used to uniquely identify the UE, so as to form a distinction with other UEs. In one implementation, the identity information of the UE may include a cell radio network temporary identity C-RNTI of the UE in a source cell; in another implementation, the identity information of the UE may include a 5G-S-TMSI of the UE; in yet another implementation, the identity information of the UE may include a portion of the 5G-S-TMSI information of the UE. It is to be understood that the identification information of the UE may include a part of the 5G-S-TMSI of the UE, meaning that the identification information of the UE may include a part of the 5G-S-TMSI that can be used to accurately identify the UE, for example, including the 5G-TMSI identification part of the 5G-S-TMSI of the UE.

a Cell Global Identity (CGI) of a source cell of the UE;

PCI of the UE source cell.

In this embodiment, the source cell identification information of the UE is used to uniquely identify the source cell of the UE, so as to form a distinction with other cells. In one implementation, the source cell identity information of the UE may include a Cell Global Identity (CGI) of a source cell of the UE; a combination of a PLMN and a Cell Identity, of a source Cell of the UE; in another implementation manner, the source cell identifier information of the UE may include a frequency point of the source cell of the UE plus a physical cell identifier PCI; in yet another implementation, the source cell identification information of the UE may include a PCI of the UE source cell.

In this embodiment, different from the above embodiments, in this embodiment, the RRC reconfiguration message is sent to the source cell of the UE through an inter-base station interface.

Based on the content of the foregoing embodiment, in this embodiment, after sending the second indication information to the source cell of the UE and sending the third indication information to the core network, the method further includes:

In this embodiment, it should be noted that, after sending the second indication information to the source cell of the UE and sending the third indication information to the core network, in order to improve the resource utilization rate of the source cell of the UE, the target cell sends sixth indication information to the source cell of the UE; the sixth indication information is used for indicating the source cell of the UE to release the context information of the UE.

The present application will be specifically described below with reference to specific examples.

The first embodiment:

as shown in fig. 6, in this embodiment, a switching procedure from direct to indiect is provided, which specifically includes the following steps:

step 1: the terminal performs relay selection.

In this step, it should be noted that the Relay selection may reuse existing mechanisms, such as: the triggering condition for the terminal to perform relay selection may be, but is not limited to, that the channel quality of the Uu interface of the terminal meets the threshold requirement. When to perform relay selection after the threshold requirement is met may depend on the UE implementation. The new relay selection trigger condition may also be used, specifically including but not limited to one or a combination of the following: a. the channel quality of a direct communication interface of a target Relay link is higher than a threshold; b. the quality of the Uu BH channel of the target Relay link is higher than a threshold; c. the Uu link channel quality is lower than the threshold; d. the continuous HARQ NACK times of the Uu interface are higher than a threshold; e. the Uu interface generates RLF.

Step 2: an RRC connection is established via the relay and the target cell.

In this step, the UE establishes RRC connection with the target cell through the relay UE. The method includes that a RRC connection establishment request message sent by UE to target network equipment needs to carry first indication information, and the first indication information is used for assisting the target network equipment to determine a source cell of the UE. Wherein the identification information of the UE may be, but is not limited to, one of the following: a. the C-RNTI of the UE in the source cell; b. 5G-S-TMSI or a portion of 5G-S-TMSI of the UE; the source cell identity of the UE may be, but is not limited to, one of: a. a Cell Global Identity (CGI) (PLMN ID + Cell ID) of a source Cell of the UE; b. a combination of PLMN and Cell Identity of the UE source Cell; c. the frequency point + PCI of the UE source cell; d. PCI of the UE source cell.

And step 3: the target cell sends a first request message to the source cell.

In this step, the behavior of the target cell after receiving the first indication information is as follows: and the target cell of the UE receives the first indication information and sends a first request message to the source cell of the UE, wherein the first request message is used for requesting context of the UE.

And 4, step 4: and the source cell sends a response message corresponding to the first request message to the target cell.

And 5: the target cell sends an RRC reconfiguration message to the UE via relay.

In this step, the target cell generates an RRC reconfiguration message according to the context of the UE acquired from the source cell, and sends the RRC reconfiguration message to the UE through the target cell.

Step 6: the UE sends an RRC reconfiguration complete message to the target cell via relay.

And 7: the target cell sends a second response message to the source cell.

In this step, after receiving the RRC reconfiguration complete message sent by the UE, the target cell sends second indication information to the source cell to notify the source cell to perform data forwarding.

And 8: the target cell sends a route switching request message to the core network.

In this step, it should be noted that, in this step 8 and the above step 7, there is no strict priority order, and after receiving the RRC reconfiguration complete message sent by the UE, the target cell sends third indication information to the core network, where the third indication information is used to request a core network to request a Path switch request (Path switch request) to request a route switch.

And step 9: a response message corresponding to step 8 is obtained.

Step 10: the target cell instructs the source cell to release the UE context.

Second embodiment:

as shown in fig. 7, in this embodiment, a switching procedure from indiect to direct is given, which specifically includes the following steps:

step 1: and the terminal executes index/direct switching judgment.

In this step, the terminal determines whether to perform indiect to direct handover, where the specific trigger condition may be, but is not limited to, one or a combination of the following: a. the channel quality of a direct communication interface of a source Relay link is lower than a threshold; b. the source Relay link Uu BH channel quality is lower than the threshold; c. the Uu link channel quality is higher than the threshold; d. UE receives indication information sent by a source relay to indicate that relay connection is released; e. the number of times of the continuous HARQ NACK of the direct communication interface of the source Relay link is higher than a threshold; f. the number of times of the source Relay link Uu BH continuous HARQ NACK is higher than a threshold; g. RLF occurs on a direct communication interface of a source Relay link; h. the source Relay link Uu BH is RLF enabled.

Step 2: an RRC connection is established with the target cell via the Uu interface.

In this step, the UE establishes RRC connection with the target cell through the Uu interface. The method includes that a RRC connection establishment request message sent by UE to target network equipment needs to carry first indication information, and the first indication information is used for assisting the target network equipment to determine a source cell of the UE. Wherein the identification information of the UE may be, but is not limited to, one of the following: a. the C-RNTI of the UE in the source cell; b. 5G-S-TMSI or a portion of 5G-S-TMSI of the UE; the source cell identity of the UE may be, but is not limited to, one of: a. a Cell Global Identity (CGI) (PLMN ID + Cell ID) of a source Cell of the UE; b. a combination of PLMN and Cell Identity of the UE source Cell; c. the frequency point + PCI of the UE source cell; d. PCI of the UE source cell.

And step 3: the target cell sends a first request message to the source cell.

In this step, the behavior of the target cell receiving the first indication information is as follows: and the target cell of the UE receives the first indication information and sends a first request message to the source cell of the UE, wherein the first request message is used for requesting context information context of the UE.

And 5: the target cell sends an RRC reconfiguration message to the UE via the Uu interface.

Step 6: the UE sends an RRC reconfiguration complete message to the target cell via Uu.

And 7: the target cell sends a second response message to the source cell.

In this step, it should be noted that, in this step 8 and step 7, there is no strict priority order, and after receiving the RRC reconfiguration complete message sent by the UE, the target cell sends third indication information to the core network, where the third indication information is used to request a core network to request a Path switch request (Path switch request) to request a Path switch.

And step 9: a response message corresponding to step 8 is obtained.

Step 10: the target cell instructs the source cell to release the UE context.

The third embodiment:

as shown in fig. 8, in this embodiment, a switching procedure from indiect to indiect is given, which specifically includes the following steps:

step 1: and the terminal executes indiect/indiect switching judgment.

In this step, the terminal determines whether handover from indiect to indiect needs to be performed, where the specific trigger condition may be, but is not limited to, one or a combination of the following: a. the channel quality of a direct communication interface of a source Relay link is lower than a threshold; b. the source Relay link Uu BH channel quality is lower than the threshold; c. the channel quality of a direct communication interface of a target Relay link is higher than a threshold; d. the quality of the Uu BH channel of the target Relay link is higher than a threshold; e. and the UE receives the indication information sent by the source relay to indicate that the relay connection is released. f. The number of times of the continuous HARQ NACK of the direct communication interface of the source Relay link is higher than a threshold; g. the number of times of the source Relay link Uu BH continuous HARQ NACK is higher than a threshold; h. RLF occurs on a direct communication interface of a source Relay link; i. the source Relay link Uu BH is RLF enabled.

Step 2: an RRC connection is established via the target relay and the target cell.

In this step, the UE establishes RRC connection with the target cell through the target relay. The method includes that a RRC connection establishment request message sent by UE to target network equipment needs to carry first indication information, and the first indication information is used for assisting the target network equipment to determine a source cell of the UE. Wherein the identification information of the UE may be, but is not limited to, one of the following: a. the C-RNTI of the UE in the source cell; b. 5G-S-TMSI or a portion of 5G-S-TMSI of the UE; the source cell identity of the UE may be, but is not limited to, one of: a. a Cell Global Identity (CGI) (PLMN ID + Cell ID) of a source Cell of the UE; b. a combination of PLMN and Cell Identity of the UE source Cell; c. the frequency point + PCI of the UE source cell; d. PCI of the UE source cell.

And step 3: the target cell sends a first request message to the source cell.

And 5: target cell sends RRC reconfiguration message to UE via target relay

Step 6: the UE sends an RRC reconfiguration complete message to the target cell via the target relay.

And 7: the target cell sends a second response message to the source cell.

And step 9: a response message corresponding to step 8 is obtained.

Step 10: the target cell instructs the source cell to release the UE context.

According to the above description, when the UE performs handover decision between direct and index links or between different index links by itself, the UE needs to carry first indication information in an RRC connection establishment request message sent to the target cell, where the first indication information is used to assist the target cell in determining the source cell of the UE, so that the target cell can determine the source cell of the UE through the first indication information carried in the RRC connection establishment request message, and thus it can be ensured that the target cell can acquire the source cell information, and thus service continuity can be ensured, and the problem in the prior art that service continuity cannot be ensured when the UE performs handover by itself is solved. Therefore, the embodiment of the application provides a processing mode capable of ensuring service continuity during direct/index connection switching, and the processing mode can ensure that data in a radio Link layer control protocol (RLC) (radio Link control) AM mode is lossless during switching.

In addition, as shown in fig. 9, a block diagram of a switching apparatus applied to a terminal device in the embodiment of the present application is shown, where the apparatus includes:

a sending module 11, configured to send a radio resource control RRC connection establishment request message to a target cell; the RRC connection establishment request message carries first indication information, and the first indication information is used for assisting the target cell in determining a source cell of terminal equipment (UE);

It should be noted that, the apparatus can implement all the method steps of the embodiment of the handover method applied to the terminal device and achieve the same technical effect, and details are not repeated herein.

In addition, as shown in fig. 10, a block diagram of a handover apparatus applied to a target cell-side network device in the embodiment of the present application is shown, where the apparatus includes:

a receiving module 21, configured to receive a radio resource control RRC connection establishment request message sent by a terminal device UE; the RRC connection establishment request message carries first indication information, and the first indication information is used for assisting a target cell to determine a source cell of the UE;

It should be noted that, the apparatus can implement all the method steps of the embodiment of the handover method applied to the target cell-side network device and achieve the same technical effect, and details are not repeated herein.

Fig. 11 is a schematic structural diagram of a terminal device according to an embodiment of the present disclosure, which includes a memory 1120, a transceiver 1100, and a processor 1110.

In fig. 11, among other things, the bus architecture may include any number of interconnected buses and bridges with various circuits being linked together, particularly one or more processors represented by processor 1110 and memory represented by memory 1120. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 1100 may be a plurality of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium including wireless channels, wired channels, fiber optic cables, and the like. The processor 1110 is responsible for managing the bus architecture and general processing, and the memory 1120 may store data used by the processor 1110 in performing operations.

The processor 1110 may be a Central Processing Unit (CPU), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or a Complex Programmable Logic Device (CPLD), and may also have a multi-core architecture.

A memory 1120 for storing a computer program; a transceiver 1100 for transceiving data under the control of the processor; a processor 1110 for reading the computer program in the memory and performing the following operations:

identification information of the UE;

source cell identification information of the UE.

Optionally, the identification information of the UE includes any one of:

the UE is in a cell radio network temporary identifier C-RNTI of a source cell;

5G-S-TMSI of the UE;

a part of information of 5G-S-TMSI of the UE.

Optionally, the source cell identity information of the UE includes any one of:

a Cell Global Identity (CGI) of a source cell of the UE;

PCI of the UE source cell.

Optionally, the handover method further includes:

judging switching;

Optionally, the handover method further includes:

judging switching;

RLF occurs at a source relay Uu interface;

Optionally, the handover method further includes:

judging switching;

RLF occurs at a source relay Uu interface;

It should be noted that the terminal device provided in the embodiment of the present application can implement all the method steps applied to the switching method embodiment of the terminal device and can achieve the same technical effect, and details are not described herein again.

Fig. 12 is a schematic structural diagram of a target cell-side network device according to an embodiment of the present application, and includes a memory 1220, a transceiver 1200, and a processor 1210.

Wherein in fig. 12, the bus architecture may include any number of interconnected buses and bridges, with one or more processors, represented by processor 1210, and various circuits, represented by memory 1220, being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 1200 may be a number of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium including wireless channels, wired channels, fiber optic cables, and the like. The processor 1210 is responsible for managing the bus architecture and general processing, and the memory 1220 may store data used by the processor 1210 in performing operations.

The processor 1210 may be a Central Processing Unit (CPU), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or a Complex Programmable Logic Device (CPLD), and may also have a multi-core architecture.

A memory 1220 for storing computer programs; a transceiver 1200 for transceiving data under the control of the processor; a processor 1210 for reading the computer program in the memory and performing the following operations:

Based on the foregoing embodiments, in this embodiment, the first indication information includes any one or more of the following information:

identification information of the UE;

source cell identification information of the UE.

Optionally, the identification information of the UE includes any one of:

the UE is in a cell radio network temporary identifier C-RNTI of a source cell;

5G-S-TMSI of the UE;

a part of information of 5G-S-TMSI of the UE.

Based on the foregoing embodiments, in this embodiment, the source cell identification information of the UE includes any one of the following items:

a Cell Global Identity (CGI) of a source cell of the UE;

PCI of the UE source cell.

Optionally, the handover method further includes:

Based on the foregoing embodiments, in this embodiment, the handover method further includes:

Based on the foregoing embodiments, in this embodiment, after sending the second indication information to the source cell of the UE and sending the third indication information to the core network, the method further includes:

It should be noted that, the target cell-side network device provided in this embodiment can implement all the method steps of the handover method embodiment applied to the target cell-side network device and can achieve the same technical effect, and details are not repeated herein.

It should be noted that the division of the unit in the embodiment of the present application is schematic, and is only a logic function division, and there may be another division manner in actual implementation. In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

The integrated unit, if implemented as a software functional unit and sold or used as a stand-alone product, may be stored in a processor readable storage medium. Based on such understanding, the technical solution of the present application may be substantially implemented or contributed by the prior art, or all or part of the technical solution may be embodied in a software product, which is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, a network device, or the like) or a processor (processor) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk, or an optical disk.

It should be noted that the apparatus provided in the embodiment of the present application can implement all the method steps implemented by the method embodiment and achieve the same technical effect, and detailed descriptions of the same parts and beneficial effects as the method embodiment in this embodiment are omitted here.

On the other hand, the embodiment of the present application further provides a processor-readable storage medium, where a computer program is stored, and the computer program is used to enable the processor to execute the method described in the foregoing embodiment.

The processor-readable storage medium can be any available medium or data storage device that can be accessed by a processor, including, but not limited to, magnetic memory (e.g., floppy disks, hard disks, magnetic tape, magneto-optical disks (MOs), etc.), optical memory (e.g., CDs, DVDs, BDs, HVDs, etc.), and semiconductor memory (e.g., ROMs, EPROMs, EEPROMs, non-volatile memory (NAND FLASH), Solid State Disks (SSDs)), etc.

As can be seen from the above embodiments, a processor-readable storage medium stores a computer program for causing the processor to perform the steps of the above handover method.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer-executable instructions. These computer-executable instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These processor-executable instructions may also be stored in a processor-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the processor-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These processor-executable instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the spirit and scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.

Claims

1. A method of handover, comprising:

2. The handover method according to claim 1, wherein the first indication information comprises any one or more of the following information:

identification information of the UE;

source cell identification information of the UE.

3. The handover method according to claim 2, wherein the identity information of the UE comprises any one of:

the UE is in a cell radio network temporary identifier C-RNTI of a source cell;

5G-S-TMSI of the UE;

a part of information of 5G-S-TMSI of the UE.

4. The handover method according to claim 2, wherein the source cell identity information of the UE comprises any one of:

a Cell Global Identity (CGI) of a source cell of the UE;

PCI of the UE source cell.

5. The handover method according to claim 1, further comprising:

6. The handover method according to claim 1, further comprising:

7. The handover method according to claim 5 or 6, further comprising:

8. The handover method according to claim 1, wherein the method further comprises: judging switching;

9. The handover method according to claim 1, wherein the method further comprises: judging switching;

RLF occurs at a source relay Uu interface;

10. The handover method according to claim 1, wherein the method further comprises: judging switching;

RLF occurs at a source relay Uu interface;

11. A method of handover, comprising:

12. The handover method according to claim 11, wherein the first indication information comprises any one or more of the following information:

identification information of the UE;

source cell identification information of the UE.

13. The handover method according to claim 12, wherein the UE identity information comprises any one of:

the UE is in a cell radio network temporary identifier C-RNTI of a source cell;

5G-S-TMSI of the UE;

a part of information of 5G-S-TMSI of the UE.

14. The handover method according to claim 12, wherein the source cell identity information of the UE comprises any one of:

a Cell Global Identity (CGI) of a source cell of the UE;

PCI of the UE source cell.

15. The handover method according to claim 11, further comprising:

16. The handover method according to claim 11, further comprising:

17. The handover method according to claim 15 or 16, further comprising:

18. The handover method according to claim 15, wherein after sending the second indication information to the source cell of the UE and sending the third indication information to the core network, the method further comprises:

19. A switching device, comprising:

20. A switching device, comprising:

21. A terminal device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor implements the following steps when executing the computer program:

22. The terminal device according to claim 21, wherein the first indication information includes any one or more of the following information:

identification information of the UE;

source cell identification information of the UE.

23. The terminal device according to claim 22, wherein the UE identity information comprises any one of:

the UE is in a cell radio network temporary identifier C-RNTI of a source cell;

5G-S-TMSI of the UE;

a part of information of 5G-S-TMSI of the UE.

24. The terminal device of claim 22, wherein the source cell identity information of the UE comprises any one of:

a Cell Global Identity (CGI) of a source cell of the UE;

PCI of the UE source cell.

25. The terminal device of claim 21, wherein the processor, when executing the computer program, is further configured to:

26. The terminal device of claim 21, wherein the processor, when executing the computer program, is further configured to:

27. A terminal device according to claim 25 or 26, wherein the processor, when executing the computer program, is further configured to perform the steps of:

28. The terminal device of claim 21, wherein the processor, when executing the computer program, is further configured to perform the determining to perform handover;

29. The terminal device of claim 21, wherein the processor, when executing the computer program, is further configured to perform the determining to perform handover;

RLF occurs at a source relay Uu interface;

30. The terminal device of claim 21, wherein the processor, when executing the computer program, is further configured to perform the determining to perform handover;

RLF occurs at a source relay Uu interface;

31. A target cell-side network device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor when executing the computer program implements the steps of:

32. The target-cell-side network device of claim 31, wherein the first indication information comprises any one or more of the following information:

identification information of the UE;

source cell identification information of the UE.

33. The target-cell-side network device of claim 32, wherein the UE identity information comprises any one of:

the UE is in a cell radio network temporary identifier C-RNTI of a source cell;

5G-S-TMSI of the UE;

a part of information of 5G-S-TMSI of the UE.

34. The target-cell-side network device according to claim 32, wherein the source cell identification information of the UE includes any one of:

a Cell Global Identity (CGI) of a source cell of the UE;

PCI of the UE source cell.

35. The target-cell-side network device of claim 31, wherein the processor, when executing the computer program, is further configured to perform the steps of:

and sending the RRC reconfiguration message to the UE.

36. The target-cell-side network device of claim 31, wherein the processor, when executing the computer program, is further configured to perform the steps of:

37. Target cell-side network device according to claim 35 or 36, wherein the processor, when executing the computer program, is further configured to perform the steps of:

38. The target-cell-side network device of claim 35, wherein the processor, when executing the computer program, is further configured to perform the steps of:

39. A processor-readable storage medium, characterized in that the processor-readable storage medium stores a computer program for causing a processor to perform the steps of the handover method of any one of claims 1 to 10, or to perform the steps of the handover method of any one of claims 11 to 18.