WO2025020012A1 - Communication method, user equipment, communication system, and storage medium - Google Patents

Abstract

The present disclosure relates to a communication method, a user equipment, a communication system, and a storage medium. The communication method comprises: a first user equipment receiving a notification message, which is sent by a second user equipment, wherein the notification message represents that the second user equipment initiates an access to a target node (S5101); and performing path handover (S5102). In this way, by means of configuring a first user equipment to perform path handover when a second user equipment initiates an access to a target node, the aim of enabling a simultaneous path change between the first user equipment and the second user equipment can be achieved.

Description

Communication method, terminal, communication system, storage medium Technical Field

The present disclosure relates to the field of communication technology, and in particular to a communication method, a terminal, a communication system, and a storage medium.

Background Art

During the HO (Handover) process, the network will configure the terminal (User Equipment, UE) to perform measurements. The network sends a handover request to the target cell based on the measurement results reported by the UE. After the target cell is confirmed, the network sends a handover command to the UE. After receiving the handover command, the UE initiates a random access process to access the target cell.

Summary of the invention

The embodiments of the present disclosure provide a communication method, a terminal, a communication system, and a storage medium. By configuring a first terminal to perform path switching when a second terminal initiates access to a target node, the first terminal and the second terminal can change the path together.

According to a first aspect of an embodiment of the present disclosure, a communication method is proposed, the method comprising:

The first terminal receives a notification message sent by the second terminal, where the notification message indicates that the second terminal initiates access to a target node; and performs path switching.

According to a second aspect of an embodiment of the present disclosure, a communication method is proposed, the method comprising:

The second terminal receives the second path switching command sent by the network device, and initiates access to the target node;

A notification message is sent to the first terminal, where the notification message indicates that the second terminal initiates access to the target node.

According to a third aspect of an embodiment of the present disclosure, a first terminal is provided, the first terminal including:

A receiving module, configured for the first terminal to receive a notification message sent by the second terminal, wherein the notification message indicates that the second terminal initiates access to the target node;

A processing module is used for the first terminal to perform path switching.

According to a fourth aspect of an embodiment of the present disclosure, a second terminal is provided, wherein the second terminal includes:

The transceiver module is used for the second terminal to receive the second path switching command sent by the network device and initiate access to the target node; and send a notification message to the first terminal, wherein the notification message indicates that the second terminal initiates access to the target node.

According to a fifth aspect of an embodiment of the present disclosure, a terminal is provided, including:

one or more processors;

The terminal is used to execute the steps of the communication method described in the first aspect or the second aspect.

According to the sixth aspect of an embodiment of the present disclosure, a communication system is proposed, comprising a first terminal and a second terminal, wherein the first terminal is configured to implement the communication method described in the first aspect, and the second terminal is configured to implement the communication method described in the second aspect.

According to a seventh aspect of the embodiments of the present disclosure, a storage medium is provided, wherein the storage medium stores instructions. When the instructions are When running on a communication device, the communication device is enabled to execute the steps of the communication method described in the first aspect or the second aspect.

By adopting the above technical solution, at least the following beneficial technical effects can be achieved:

By configuring the first terminal to perform path switching when the second terminal initiates access to the target node, the purpose of changing the path of the first terminal and the second terminal together can be achieved.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings required for describing the embodiments are introduced below. The following drawings are only some embodiments of the present disclosure and do not impose specific limitations on the protection scope of the present disclosure.

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

FIG1b is a schematic diagram of the architecture of a communication system according to an embodiment of the present disclosure.

FIG. 2 is an interactive schematic diagram of a communication method according to an embodiment of the present disclosure.

FIG. 3 a is a flow chart of a communication method according to an embodiment of the present disclosure.

FIG3 b is a flow chart of a communication method according to an embodiment of the present disclosure.

FIG3c is a flow chart of a communication method according to an embodiment of the present disclosure.

FIG3d is a flow chart of a communication method according to an embodiment of the present disclosure.

FIG4 a is a flow chart of a communication method according to an embodiment of the present disclosure.

FIG4b is a flow chart of a communication method according to an embodiment of the present disclosure.

FIG5a is a schematic diagram of a communication method according to an embodiment of the present disclosure.

FIG5 b is a schematic diagram of a communication method according to an embodiment of the present disclosure.

FIG. 6 a is a schematic diagram of the structure of a terminal proposed in an embodiment of the present disclosure.

FIG. 6 b is a schematic diagram of the structure of a terminal proposed in an embodiment of the present disclosure.

FIG. 7 a is a schematic diagram of the structure of a communication device proposed in an embodiment of the present disclosure.

FIG. 7 b is a schematic diagram of the structure of a chip proposed in an embodiment of the present disclosure.

DETAILED DESCRIPTION

Embodiments of the present disclosure provide a communication method, a terminal, a communication system, and a storage medium.

In a first aspect, an embodiment of the present disclosure provides a communication method, the method comprising:

The first terminal receives a notification message sent by the second terminal, where the notification message indicates that the second terminal initiates access to a target node; and performs path switching.

In the above embodiment, by configuring the first terminal to perform path switching when the second terminal initiates access to the target node, the purpose of changing the path of the first terminal and the second terminal together can be achieved.

In combination with some embodiments of the first aspect, in some embodiments, before performing the path switching, it includes: determining that the notification message includes a path change indication.

In the above embodiment, when the second terminal initiates access to the target node, the first terminal determines to perform path switching according to the path change indication, thereby achieving the purpose of the first terminal changing the path together with the second terminal according to the indication, and is compatible with the scenario in which the first terminal and the second terminal change the path together, and is compatible with the scenario in which the first terminal and the second terminal do not change the path together.

In combination with some embodiments of the first aspect, in some embodiments, the first terminal has a first path switching command;

Before performing the path switching, it includes: determining that the notification message includes a path change indication; and determining that the target node identifier in the first path switching command is consistent with the target node identifier in the path change indication.

In the above embodiment, when the first terminal initiates access to the target node, if it is determined that the target node identifier in the first path switching command is consistent with the target node identifier in the path change indication, the path switching is performed. In this way, the purpose of the first terminal and the second terminal changing the path to the target node together can be achieved.

In combination with some embodiments of the first aspect, in some embodiments, the method further includes:

It is determined that the target node identifier in the first path switching command is inconsistent with the target node identifier in the path change indication, and RRC reconstruction is triggered.

In the above embodiment, when the first terminal initiates access to the target node at the second terminal, if it is determined that the target node identifier in the first path switching command is inconsistent with the target node identifier in the path change indication, RRC reconstruction is triggered to restore the RRC signaling connection and reduce disconnection.

In combination with some embodiments of the first aspect, in some embodiments, the target node identifier is a cell identifier or a relay terminal identifier.

In the above embodiment, the purpose of the first terminal and the second terminal changing the path to the cell or the relay terminal together can be achieved.

In conjunction with some embodiments of the first aspect, in some embodiments, the first path switching command on the first terminal includes a first configuration, wherein the first configuration includes at least one of a bearer configuration, a MAC configuration, and a random access configuration;

The performing path switching includes: performing path switching according to the first configuration, and starting a first timer.

In the above embodiment, when the first terminal and the second terminal change the path together, the first terminal can perform path switching according to at least one of the bearer configuration, MAC configuration, and random access configuration, and this method supports path switching of multiple configurations. In addition, it is specified that when the first terminal performs path switching, the first timer is started to assist.

In combination with some embodiments of the first aspect, in some embodiments, it is determined that the first timer has timed out, triggering RRC reconstruction.

In the above embodiment, during the process of the first terminal and the second terminal changing the path together, if the first timer times out, RRC reconstruction is triggered to restore the RRC signaling connection and reduce disconnection.

In conjunction with some embodiments of the first aspect, in some embodiments, the first path switching command further includes the duration of the first timer;

The method further includes: determining whether the first timer has timed out according to the duration of the first timer.

In the above embodiment, the duration of the first timer can be configured according to the first path switching command, which provides a way to configure the duration of the first timer.

In combination with some embodiments of the first aspect, in some embodiments, the method further includes:

Receive a first indication message sent by the second terminal, wherein the first indication message indicates that the second terminal successfully accesses the target Node: stop the first timer.

In the above embodiment, during the process of the first terminal and the second terminal changing the path together, if the first terminal determines that the second terminal successfully accesses the target node, the first timer is stopped to avoid triggering redundant steps of RRC reconstruction due to the timeout of the first timer.

In combination with some embodiments of the first aspect, in some embodiments, the method further includes:

A second indication message sent by the second terminal is received, where the second indication message indicates that the second terminal fails to access the target node; and RRC reconstruction is triggered.

In the above embodiment, during the process of the first terminal and the second terminal changing the path together, if the second terminal fails to access the target node, RRC reconstruction is triggered to restore the RRC signaling connection and reduce disconnection.

In combination with some embodiments of the first aspect, in some embodiments, the method further includes:

Stop the first timer.

In the above embodiment, when the RRC reconstruction is triggered, the first timer is stopped to avoid the redundant step of triggering the RRC reconstruction again due to the timeout of the first timer.

In combination with some embodiments of the first aspect, in some embodiments, the method further includes:

Receiving the first path switching command sent by the network device;

The first path switching command is stored.

In the above embodiment, the network device sends the first path switching command to the first terminal, and the first terminal stores the first path switching command, so as to increase the usage time limit of the first path switching command and avoid the problem of resource waste caused by continuously sending the first path switching command.

In combination with some embodiments of the first aspect, in some embodiments, the path switching is group path switching;

During the group path switching process, the first terminal maintains connection with the second terminal.

In the above embodiment, in the process of the first terminal and the second terminal changing the path together, maintaining the connection between the first terminal and the second terminal can reduce signaling consumption and avoid service interruption of the first terminal, thereby achieving the purpose of the first terminal and the second terminal changing the path to the target node together.

In a second aspect, an embodiment of the present disclosure provides a communication method, the method comprising:

The second terminal receives the second path switching command sent by the network device, and initiates access to the target node;

A notification message is sent to the first terminal, where the notification message indicates that the second terminal initiates access to the target node.

In the above embodiment, by configuring the second terminal to send a notification message to the first terminal when initiating access to the target node, the first terminal can obtain a path change opportunity and then change the path together with the second terminal.

In combination with some embodiments of the second aspect, in some embodiments, the second path switching command includes a target node identifier, and the target node is determined based on the target node identifier; and/or the second path switching command includes a first terminal identifier, and the first terminal is determined based on the first terminal identifier.

In the above embodiment, by configuring the second path switching command, the target node accessed by the second terminal and the object to which the notification message is sent can be flexibly controlled.

In combination with some embodiments of the second aspect, in some embodiments, the notification message includes a path change indication, the path change indication includes the target node identifier, and the target node identifier is used by the first terminal to determine to perform a path switch or trigger RRC reconstruction.

In the above embodiment, by configuring the notification message, the first terminal can be instructed to perform path switching with the second terminal or to trigger RRC reconstruction, thereby reducing the offline duration of the first terminal or avoiding the offline of the first terminal.

In conjunction with some embodiments of the second aspect, in some embodiments, the second path switching command includes a first configuration, wherein the first configuration includes at least one of a bearer configuration, a MAC configuration, and a random access configuration;

The initiating access to the target node includes: initiating access to the target node according to the first configuration, and starting a second timer.

In the above embodiment, when the second terminal initiates access to the target node, the second timer is started to assist in determining whether the second terminal fails to access.

In conjunction with some embodiments of the second aspect, in some embodiments, the method further includes:

Determining that the target node is successfully accessed, and stopping the second timer;

A first indication message is sent to the first terminal, where the first indication message is used to instruct the first terminal to stop a first timer.

In conjunction with some embodiments of the second aspect, in some embodiments, the target node identifier of the target node is a cell identifier;

The determining that the target node is successfully accessed includes:

Successful access to the target node is determined based on successful completion of the random access process.

In the above embodiment, whether the second terminal successfully accesses the cell may be determined by whether the random access process is successfully completed.

In conjunction with some embodiments of the second aspect, in some embodiments, the target node identifier of the target node is a relay terminal identifier;

The determining that the target node is successfully accessed includes:

Successful access to the target node is determined based on successful sending of the RRC connection reconfiguration complete message.

In the above embodiment, whether the second terminal successfully accesses the relay terminal can be determined by whether the RRC connection reconfiguration complete message is successfully sent.

In conjunction with some embodiments of the second aspect, in some embodiments, the method further includes:

Determine that access to the target node fails, and send a second indication message to the first terminal, where the second indication message is used to instruct the first terminal to trigger RRC reconstruction.

In conjunction with some embodiments of the second aspect, in some embodiments, determining that access to the target node fails includes:

When the second timer times out, it is determined that access to the target node fails.

In combination with some embodiments of the second aspect, in some embodiments, the second timer is T304 or T420.

In a third aspect, an embodiment of the present disclosure proposes a first terminal, which includes at least one of a receiving module and a processing module, and the first terminal is used to execute an implementation method of the first aspect or an optional implementation method of the first aspect.

In a fourth aspect, an embodiment of the present disclosure proposes a second terminal, which includes a transceiver module, and the second terminal is used to execute the implementation method of the second aspect or the optional implementation method of the second aspect.

In a fifth aspect, an embodiment of the present disclosure proposes a terminal, comprising: one or more processors; wherein the terminal is used to execute the implementation method of the first aspect or the optional implementation method of the first aspect, or the terminal is used to execute the implementation method of the second aspect or the optional implementation method of the second aspect.

In a sixth aspect, an embodiment of the present disclosure proposes a communication system, comprising a first terminal and a second terminal, wherein the first terminal is configured to execute a communication method as described in an implementation manner of the first aspect or an optional implementation manner of the first aspect, and the second terminal is configured to execute a communication method as described in an implementation manner of the second aspect or an optional implementation manner of the second aspect.

In the seventh aspect, an embodiment of the present disclosure proposes a storage medium, which stores instructions. When the instructions are executed on a communication device, the communication device executes the communication method described in the implementation of the first aspect or the optional implementation of the first aspect, or the communication device executes the communication method described in the implementation of the second aspect or the optional implementation of the second aspect.

In an eighth aspect, an embodiment of the present disclosure proposes a program product. When the program product is executed by a communication device, the communication device executes the communication method described in the implementation of the first aspect or the optional implementation of the first aspect, or the communication device executes the communication method described in the implementation of the second aspect and the optional implementation of the second aspect.

In the ninth aspect, an embodiment of the present disclosure proposes a computer program, which, when running on a computer, enables the computer to execute the communication method described in the implementation of the first aspect, the implementation of the second aspect, the optional implementation of the first aspect, or the optional implementation of the second aspect.

In a tenth aspect, an embodiment of the present disclosure provides a chip or a chip system. The chip or chip system includes a processing circuit, and the processing circuit is configured to execute the communication method described in the implementation of the first aspect, the implementation of the second aspect, the optional implementation of the first aspect, or the optional implementation of the second aspect.

It can be understood that the above-mentioned first terminal, second terminal, terminal, communication system, storage medium, program product, computer program, chip or chip system are all used to execute the communication method proposed in the embodiment of the present disclosure. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding method, which will not be repeated here.

The embodiments of the present disclosure provide a communication method, a terminal, a communication system, and a storage medium. In some embodiments, the terms such as the communication method, the information processing method, the path switching/changing method, etc. can be replaced with each other, the terms such as the communication device, the information processing device, the path switching/changing device, etc. can be replaced with each other, and the terms such as the communication system, the information processing system, the path switching/changing system, etc. can be replaced with each other.

The embodiments of the present disclosure are not exhaustive, but are only illustrative of some embodiments, and are not intended to be a specific limitation on the scope of protection of the present disclosure. In the absence of contradiction, each step in a certain embodiment can be implemented as an independent embodiment, and the steps can be arbitrarily combined. For example, a solution after removing some steps in a certain embodiment can also be implemented as an independent embodiment, and the order of the steps in a certain embodiment can be arbitrarily exchanged. In addition, the optional implementation methods in a certain embodiment can be arbitrarily combined; in addition, the embodiments can be arbitrarily combined, for example, some or all of the steps of different embodiments can be arbitrarily combined, and a certain embodiment can be arbitrarily combined with the optional implementation methods of other embodiments.

In each embodiment of the present disclosure, if there is no special explanation and logical conflict, the terms and/or descriptions between the embodiments are consistent and can be referenced to each other. The technical features of different embodiments can be combined to form a new embodiment according to their inherent logical relationship. Embodiment of the invention.

The terms used in the embodiments of the present disclosure are only for the purpose of describing specific embodiments and are not intended to limit the present disclosure.

In the embodiments of the present disclosure, unless otherwise specified, elements expressed in the singular form, such as "a", "an", "the", "above", "said", "aforementioned", "this", etc., may mean "one and only one", or "one or more", "at least one", etc. For example, when using articles such as "a", "an", "the" in English in translation, the noun after the article may be understood as a singular expression or a plural expression.

In the embodiments of the present disclosure, “plurality” refers to two or more.

In some embodiments, the terms "at least one of", "one or more", "a plurality of", "multiple", etc. can be used interchangeably.

In some embodiments, "at least one of A and B", "A and/or B", "A in one case, B in another case", "in response to one case A, in response to another case B", etc., may include the following technical solutions according to the situation: in some embodiments, A (A is executed independently of B); in some embodiments, B (B is executed independently of A); in some embodiments, execution is selected from A and B (A and B are selectively executed); in some embodiments, A and B (both A and B are executed). When there are more branches such as A, B, C, etc., the above is also similar.

In some embodiments, the recording method of "A or B" may include the following technical solutions according to the situation: in some embodiments, A (A is executed independently of B); in some embodiments, B (B is executed independently of A); in some embodiments, execution is selected from A and B (A and B are selectively executed). When there are more branches such as A, B, C, etc., the above is also similar.

The prefixes such as "first" and "second" in the embodiments of the present disclosure are only used to distinguish different description objects, and do not constitute restrictions on the position, order, priority, quantity or content of the description objects. The statement of the description object refers to the description in the context of the claims or embodiments, and should not constitute unnecessary restrictions due to the use of prefixes. For example, if the description object is a "field", the ordinal number before the "field" in the "first field" and the "second field" does not limit the position or order between the "fields", and the "first" and "second" do not limit whether the "fields" they modify are in the same message, nor do they limit the order of the "first field" and the "second field". For another example, if the description object is a "level", the ordinal number before the "level" in the "first level" and the "second level" does not limit the priority between the "levels". For another example, the number of description objects is not limited by the ordinal number, and can be one or more. Taking the "first device" as an example, the number of "devices" can be one or more. In addition, the objects modified by different prefixes may be the same or different. For example, if the description object is "device", then the "first device" and the "second device" may be the same device or different devices, and their types may be the same or different. For another example, if the description object is "information", then the "first information" and the "second information" may be the same information or different information, and their contents may be the same or different.

In some embodiments, “including A”, “comprising A”, “used to indicate A”, and “carrying A” can be interpreted as directly carrying A or indirectly indicating A.

In some embodiments, terms such as "in response to ...", "in response to determining ...", "in the case of ...", "at the time of ...", "when ...", "if ...", "if ...", etc. can be used interchangeably.

In some embodiments, terms such as "greater than", "greater than or equal to", "not less than", "more than", "more than or equal to", "not less than", "higher than", "higher than or equal to", "not lower than", and "above" can be replaced with each other, and terms such as "less than", "less than or equal to", "not greater than", "less than", "less than or equal to", "no more than", "lower than", "lower than or equal to", "not higher than", and "below" can be replaced with each other.

In some embodiments, devices and equipment may be interpreted as physical or virtual, and their names are not limited to the names recorded in the embodiments. In some cases, they may also be understood as "equipment", "device", "circuit", "network element", "node", "function", "unit", "section", "system", "network", "chip", "chip system", "entity", "subject", etc.

In some embodiments, "network" can be interpreted as devices included in the network, such as access network equipment, core network equipment, etc.

In some embodiments, "access network device (AN device)" may also be referred to as "radio access network device (RAN device)", "base station (BS)", "radio base station (radio base station)", "fixed station" and in some embodiments may also be understood as "node", "access point (access point)", "transmission point (TP)", "reception point (RP)", "transmission and/or reception point (transmission/reception point, TRP)", "panel", "antenna panel", "antenna array", "cell", "macro cell", "small cell", "femto cell", "pico cell", "sector", "cell group", "serving cell", "carrier", "component carrier", "bandwidth part (bandwidth part, BWP)", etc.

In some embodiments, the term "terminal" or "terminal device" may be referred to as "user equipment (UE)", "user terminal (user terminal)", "mobile station (MS)", "mobile terminal (MT)", subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, etc.

In the embodiments of the present disclosure, data, information, etc. may be obtained in accordance with the laws and regulations of the country where the data is located.

In some embodiments, data, information, etc. may be obtained with the user's consent.

In addition, each element, each row, or each column in the table of the embodiments of the present disclosure may be implemented as an independent embodiment, and the combination of any elements, any rows, and any columns may also be implemented as an independent embodiment.

Although operations are described in a particular order in the drawings in the embodiments of the present disclosure, it should not be understood that it is required to perform these operations in the particular order shown or in serial order, or that all of the shown operations must be performed to obtain desired results. In certain circumstances, multitasking and parallel processing may be advantageous. In addition, sending multiple information via the same message may also be advantageous.

FIG1a is a schematic diagram of the architecture of a communication system according to an embodiment of the present disclosure. As shown in FIG1a , a communication system 100 includes a first terminal 101 and a second terminal 102 .

In some embodiments, the first terminal 101 and/or the second terminal 102 include, for example, a mobile phone, a wearable device, an Internet of Things device, a car with communication function, a smart car, a tablet computer (Pad), a computer with wireless transceiver function, a virtual reality (VR) terminal device, an augmented reality (AR) terminal device, a wireless terminal device in industrial control (industrial control), a wireless terminal device in self-driving, a wireless terminal device in remote medical surgery, a wireless terminal device in a smart grid (smart grid), a wireless terminal device in transportation safety (transportation safety), a wireless terminal device in a smart city (smart city), and at least one of a wireless terminal device in a smart home (smart home), but not limited to these.

In some embodiments, the technical solution of the present disclosure may be applicable to the Open RAN architecture. In this case, the interfaces between access network devices or within access network devices involved in the embodiments of the present disclosure may become internal interfaces of Open RAN, and the processes and information interactions between these internal interfaces may be implemented through software or programs.

In some embodiments, the access network device may be composed of a centralized unit (central unit, CU) and a distributed unit (distributed unit, DU), wherein the CU may also be called a control unit (control unit). The CU-DU structure may be used to split the protocol layer of the access network device, with some functions of the protocol layer being centrally controlled by the CU, and the remaining part or all of the functions of the protocol layer being distributed in the DU, and the DU being centrally controlled by the CU, but not limited to this.

It can be understood that the communication system described in the embodiment of the present disclosure is for the purpose of more clearly illustrating the technical solution of the embodiment of the present disclosure, and does not constitute a limitation on the technical solution proposed in the embodiment of the present disclosure. A person of ordinary skill in the art can know that with the evolution of the system architecture and the emergence of new business scenarios, the technical solution proposed in the embodiment of the present disclosure is also applicable to similar technical problems.

The following embodiments of the present disclosure may be applied to the communication system 100 shown in FIG. 1a, or part of the subject, but are not limited thereto. The subjects shown in FIG. 1a are examples, and the communication system may include all or part of the subjects in FIG. 1a, or may include other subjects other than FIG. 1a, and the number and form of the subjects are arbitrary, and the subjects may be physical or virtual, and the connection relationship between the subjects is an example, and the subjects may be connected or disconnected, and the connection may be in any manner, and may be a direct connection or an indirect connection, and may be a wired connection or a wireless connection.

In some embodiments, the communication system 100 includes a first terminal 101, a second terminal 102, and a network device.

In some embodiments, the network device may include at least one of an access network device and a core network device.

Optionally, the access network device is, for example, a node or device that accesses the terminal to the wireless network. The access network device may include an evolved NodeB (eNB), a next generation evolved NodeB (ng-eNB), a next generation NodeB (gNB), a node B (NB), a home node B (HNB), a home evolved node B (HeNB), a wireless backhaul device, a wireless At least one of a radio network controller (RNC), a base station controller (BSC), a base transceiver station (BTS), a base band unit (BBU), a mobile switching center, a base station in a 6G communication system, an open base station (Open RAN), a cloud base station (Cloud RAN), a base station in other communication systems, and an access node in a Wi-Fi system, but not limited thereto.

In some embodiments, the network device is a base station.

Optionally, the base station is, for example, a macro base station, a micro base station (also called a small station), a relay station, an access point, a 5G base station or a future base station, a satellite, a transmission point (Transmitting and Receiving Point, TRP), a transmitting point (Transmitting Point, TP), a mobile switching center, or other devices that assume the function of a base station in a communication system, etc., which are not specifically limited in the embodiments of the present disclosure. For the convenience of description, in all embodiments of the present disclosure, the devices that provide wireless communication functions for terminal devices are collectively referred to as network devices or base stations.

In some embodiments, the core network device may be a device including a first network element, a second network element, etc., or may be a plurality of devices or a group of devices including all or part of the first network element, the second network element, etc. The network element may be virtual or physical. The core network may include, for example, at least one of an Evolved Packet Core (EPC), a 5G Core Network (5GCN), and a Next Generation Core (NGC).

The embodiments of the present disclosure may be applied to Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, the fourth generation mobile communication system (4G), the fifth generation mobile communication system (5G), 5G new radio (NR), Future Radio Access (FRA), New-Radio Access Technology (RAT), New Radio (NR), New radio access (NX), Future generation radio access ... The present invention relates to wireless communication systems such as LTE, Wi-Fi (X), Global System for Mobile communications (GSM (registered trademark)), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), Public Land Mobile Network (PLMN) network, Device to Device (D2D) system, Machine to Machine (M2M) system, Internet of Things (IoT) system, Vehicle to Everything (V2X), systems using other communication methods, and next-generation systems expanded based on them. In addition, a combination of multiple systems (for example, a combination of LTE or LTE-A with 5G, etc.) may also be applied.

In the disclosed embodiment, during the path switching HO (Handover) process, the network will configure the UE to perform measurements, and the network will send a handover request to the target cell of the handover according to the measurement results reported by the UE. After the target cell is confirmed, the network sends a handover command to the UE, such as sending a Reconfiguration with sync signaling. The handover command may carry the configuration information of the target cell, which may include bearer configuration, MAC configuration and random access configuration. After the UE receives the handover command, the UE will synchronize with the target cell, then initiate a random access process to access the target cell, and start using the configuration of the target cell.

In some embodiments of the present disclosure, as shown in FIG. 1b , a UE may not be directly connected to a base station but may be connected to another base station through another The relay function of UE realizes communication with the base station. The UE that is not connected to the base station is called remote UE, and the UE that provides relay function is called relay UE. The remote UE and relay UE communicate through Sidelink unicast. This architecture is called U2N (UE to Network, also known as UE to NW) relay. In this way, even if the remote UE cannot receive the base station signal, the remote UE can still communicate with the network through the relay UE, thereby expanding the coverage of the network. Among them, the direct communication interface between UE and UE is PC-5. The communication between UE and base station is realized through the cellular network communication interface Uu.

As shown in Figure 1b, the remote UE and the base station can implement related communications of the Service Data Adaptation Protocol (SDAP) and the Packet Data Convergence Protocol (PDCP) through the Uu interface.

Continuing to refer to Figure 1b, the Sidelink Relay Adaptation Protocol (SRAP), Radio Link Control (RLC), Medium Access Control (MAC), and Physical layer (PHY) related communications can be implemented between the remote UE and the relay UE through the PC-5 interface.

According to the corresponding relationship between the sending UE and the receiving UE, three data transmission modes are supported on the sidelink, namely unicast, multicast and broadcast. A unicast connection is established between UEs, that is, a PC5-RRC (RRC: Radio Resource Control) connection is established. After the unicast connection is established, PC5-RRC messages can be exchanged between UEs.

When the relay UE experiences a radio link failure (Radio Link Failure), handover, cell reselection, or RRC connection failure, a notification message can be sent to the connected remote UE via the sidelink, such as NotificationMessageSidelink signaling. When the remote UE receives the notification message, the remote UE in the CONNECTED state triggers a reestablishment, and the remote UE in the IDLE state and the INACTIVE state can decide whether to release the connection with the relay UE. If the connection with the relay UE is not released, and if the notification message indicates that the relay UE has undergone a handover/cell reselection, the remote UE also believes that it has undergone a handover/cell reselection.

In the disclosed embodiment, the network may switch the path of the remote UE from one relay UE to another relay UE. For example, the network sends a path switching signaling to the remote UE, such as sending a pathswitch signaling, which may carry the identifier of the target relay UE. After the remote UE receives the path switching signaling, the remote UE establishes a sidelink unicast connection with the target relay UE, and then the remote UE can transmit data with the network through the target relay UE.

In the embodiment of the present disclosure, if the network switches the path of the remote UE from the relay UE to a direct connection with the cell, the traditional switching process is reused.

In the disclosed embodiment, the architecture in which the remote UE maintains connection with the network through multiple relay UEs is called multi-hop U2N relay (Multi-hop U2N relay).

In the disclosed embodiment, the relay UE and the connected remote UE change the path together, which is called group mobility.

The present disclosure provides an implementation manner, in which the network may first switch the remote UE to another path, then switch the relay UE to the new path, and then switch the remote UE back to the relay UE, however, this approach may cause additional signaling consumption.

The present disclosure also provides another implementation mode, if the remote UE has no other path to switch, the remote UE can release the connection with the relay UE. After switching the relay UE to a new path, the remote UE reconnects to the relay UE. However, this method may cause service interruption of the remote UE.

Furthermore, the present disclosure provides a communication method and system to reduce signaling consumption and avoid service interruption of the remote UE during the process of changing the path between the relay UE and the connected remote UE.

The following describes an embodiment based on an example in which the first terminal 101 is a remote UE of the second terminal 102 and the second terminal 102 is a relay UE of the first terminal 101 .

FIG2 is an interactive schematic diagram of a communication method according to an embodiment of the present disclosure. As shown in FIG2 , the present disclosure embodiment relates to a communication method, which is used in a communication system 100, and the method includes:

Step S201: The network device sends a first path switching command to the first terminal 101.

In some embodiments, terms such as "send", "transmit", "report", "send", "transmit", "bidirectional transmission", "send and/or receive" can be used interchangeably.

In some embodiments, the first terminal 101 receives the first path switching command. Optionally, the first terminal 101 stores the first path switching command. In this way, the usage time limit of the first path switching command can be increased, avoiding the problem of resource waste caused by continuously sending the first path switching command to the first terminal 101.

In some embodiments, the first path switching command is used to configure parameters used/involved in the path switching process.

In some embodiments, the first path switching command is used to configure parameters used/involved in the path switching process of the remote UE.

In some embodiments, the name of the first path switching command is not limited, and it may be, for example, a group path switching command, a path change command, a path switching configuration, a switching signaling, etc.

In some embodiments, the first path switching command includes at least one of a target node identifier, a first configuration, and a duration of a first timer. The name of the target node identifier is not limited, and it is, for example, a node identifier, a node ID, a node unique identifier, etc. Optionally, the target node identifier is a cell identifier or a relay terminal identifier. Optionally, the first configuration includes at least one of a bearer configuration, a MAC configuration, and a random access configuration.

In some embodiments, the network device sends a reconfiguration with sync synchronous reconfiguration signaling, and the reconfiguration with sync signaling carries or includes the first path switching command. Optionally, the first terminal 101 receives the reconfiguration with sync signaling to obtain the first path switching command.

In some embodiments, the network device sends a pathswitch signaling, and the pathswitch signaling carries or includes the first path switching command. Optionally, the first terminal 101 receives the pathswitch signaling to obtain the first path switching command.

In some embodiments, the implementation method of the network device sending the first path switching command to the first terminal 101 may be: the network device sends the first path switching command to the first terminal 101 through the relay function of the second terminal 102.

In some embodiments, the first terminal 101 can be directly connected to the network device, and at the same time, the first terminal 101 can also be connected to the network device through the second terminal 102. Based on this, the network device sends a first path switching command to the first terminal 101 An implementation method may be: the network device directly sends a first path switching command to the first terminal 101.

Step S202: The network device sends a second path switching command to the second terminal 102.

In some embodiments, the second terminal 102 receives a second path switching command.

In some embodiments, the second path switching command is used to configure parameters used/involved in the path switching process.

In some embodiments, the second path switching command is used to configure parameters used/involved in the path switching process of the relay UE.

In some embodiments, the name of the second path switching command is not limited, and it may be, for example, a group path switching command, a path switching command, a path switching configuration, a switching signaling, etc.

In some embodiments, the second path switching command includes at least one of a target node identifier, a first terminal identifier, and a first configuration. Wherein, the name of the target node identifier is not limited, and it is, for example, a node identifier, a node ID, a node unique identifier, etc. Optionally, the target node identifier is a cell identifier or a relay terminal identifier. Optionally, the first configuration includes at least one of a bearer configuration, a MAC configuration, and a random access configuration. In some embodiments, the name of the first terminal identifier is not limited, and it is, for example, a terminal ID, a terminal unique identifier, etc.

In some embodiments, the network device sends a reconfiguration with sync synchronous reconfiguration signaling, and the reconfiguration with sync signaling carries or includes the second path switching command. Optionally, the second terminal 102 receives the reconfiguration with sync signaling to obtain the second path switching command.

In some embodiments, the network device sends a path switch signaling, and the path switch signaling carries or includes the second path switch command. Optionally, the second terminal 102 receives the path switch signaling to obtain the second path switch command.

In some embodiments, the second terminal 102 may be directly connected to the network device, or the second terminal 102 may be connected to the network device through other relay terminals, which is not limited in the present disclosure.

Based on this, the implementation method of the network device sending the second path switching command to the second terminal 102 may be: the network device directly sends the second path switching command to the second terminal 102. Alternatively, the network device sends the second path switching command to the second terminal 102 through other relay terminals connected to the second terminal 102.

Optionally, the first path switching command is the same as the second path switching command.

Step S203: The second terminal 102 initiates access to the target node.

Optionally, the target node is a cell or a relay terminal.

Optionally, the target node is determined according to a target node identifier. Optionally, the target node identifier is carried in the second path switching command.

In some embodiments, the target node is used to indicate a node that the second terminal is going to access. The name of the target node is not limited, and it can be, for example, a network device, an access network device, a network element, and the like.

In some embodiments, in response to receiving the second path switching command, the second terminal 102 initiates access to the target node.

In some embodiments, the second terminal 102 initiates access to the target node simultaneously with or after receiving the second path switching command.

In some embodiments, the step of the second terminal 102 initiating access to the target node may be: the second terminal 102 initiates access to the target node according to the first configuration. Optionally, the first configuration is carried in the second path switching command. Optionally, when the second terminal 102 initiates access to the target node, a second timer is started. In this way, when the second terminal 102 initiates access to the target node, the second timer is started to assist in determining whether the second terminal 102 fails to access the target node.

Step S204: The second terminal 102 sends a notification message to the first terminal 101.

Optionally, the first terminal 101 receives a notification message.

In some embodiments, the first terminal 101 is determined by the second terminal 102 according to the first terminal identifier. Optionally, the first terminal identifier is carried in the second path switching command. Optionally, the first terminal identifier is used by the second terminal 102 to determine the object to which the notification message is sent. The name of the first terminal identifier is not limited, and it is, for example, a terminal ID, a terminal unique identifier, etc.

In some embodiments, the notification message is used to notify the first terminal 101 that the second terminal 102 initiates access to the target node.

In some embodiments, the notification message is used to notify the remote UE that the relay UE initiates access to the target node.

In some embodiments, the notification message is used to notify the remote UE that it is time for it to perform path switching with the relay UE.

In some embodiments, the notification message is used to instruct the first terminal 101 to perform path switching.

In some embodiments, the notification message is used to carry a path change indication, and the path change indication is used to instruct the first terminal 101 to perform a path switch.

In some embodiments, the notification message is used to carry a target node identifier, and the target node identifier carried in the notification message is used by the first terminal 101 to determine whether to perform a path switch. Optionally, the target node identifier is used by the first terminal 101 to determine whether to perform a path switch or trigger an RRC reconstruction. Optionally, the first terminal 101 determines whether to perform a path switch based on the target node identifier carried in the notification message and the target node identifier in the first path switch command. Optionally, the notification message carries a path change indication, and the path change indication includes the target node identifier.

Among them, RRC reconstruction means that the first terminal initiates an RRC reconstruction request (RRCRe-establishmentRequest) to the adjacent gNB cell; after receiving the request, the NB requests the base station nearest to the first terminal (LastServicegNB) to retrieve the first terminal context.

In some embodiments, the second terminal 102 sends NotificationMessageSidelink sidelink notification information, where NotificationMessageSidelink carries or includes a notification message. Optionally, the first terminal 101 receives NotificationMessageSidelink to obtain the notification message.

Step S205: the first terminal 101 performs path switching.

In some embodiments, the path switching may be a group path switching. Optionally, the group path switching refers to a path switching mode in which the relay UE and the connected remote UE switch paths to the same target node, and during the path switching process, the relay UE and the remote UE maintain a sidelink connection.

Optionally, the first terminal 101 executes step S205 in response to receiving the notification message. In this way, by configuring the first terminal to perform path switching when the second terminal initiates access to the target node, the purpose of changing the path together with the second terminal can be achieved.

Optionally, the first terminal 101 executes step S205 in response to receiving a notification message including a path change indication. In this way, when the second terminal initiates access to the target node, the first terminal determines to perform path switching according to the path change indication, thereby achieving the purpose of the first terminal changing the path together with the second terminal according to the indication, and is compatible with the scenario in which the first terminal and the second terminal change the path together, and is compatible with the scenario in which the first terminal and the second terminal do not change the path together.

Optionally, the first terminal 101 determines that the target node identifier in the first path switching command is consistent with the target node identifier in the path change indication, and executes step S205. In this way, when the first terminal initiates access to the target node by the second terminal, if it is determined that the target node identifier in the first path switching command is consistent with the target node identifier in the path change indication, the path switching is performed. In this way, the purpose of changing the path to the target node together with the second terminal can be achieved.

In some embodiments, the step of the first terminal 101 performing path switching may be: performing path switching according to a first configuration. Optionally, the first configuration is carried in a first path switching command.

Step S206: The first terminal 101 starts a first timer.

In some embodiments, the first timer is used to perform path switching timing for the first terminal 101.

Optionally, when performing path switching, the first terminal 101 executes step S206, and the first terminal 101 starts a first timer.

Step S207: The second terminal 102 sends a first indication message to the first terminal 101.

Optionally, the first terminal 101 receives the first indication information. Optionally, the first indication message indicates that the second terminal successfully accesses the target node.

In some embodiments, the second terminal 102 successfully accesses the target node and stops the second timer. Optionally, when stopping the second timer, the second terminal 102 executes step S207 to send a first indication message to the first terminal 101.

In some embodiments, the first indication message is used to instruct the first terminal to stop the first timer.

In some embodiments, the first indication information is used to notify the first terminal 101 that the second terminal 102 has successfully accessed the target node.

In some embodiments, the name of the first indication information is not limited, and it is, for example, a first timer stop instruction.

In some embodiments, the second terminal 102 sends NotificationMessageSidelink sidelink notification information, and the NotificationMessageSidelink carries or includes the first indication information. Optionally, the first terminal 101 receives the NotificationMessageSidelink to obtain the first indication information.

In some embodiments, if the target node identifier of the target node is a cell identifier, the terminal 102 may determine that the target node is successfully accessed by: determining that the second terminal 102 successfully accesses the target node based on the second terminal 102 successfully completing the random access process. Optionally, the second timer is T304.

In some embodiments, if the target node identifier of the target node is a relay terminal identifier, then the implementation method of determining successful access to the target node may be: the second terminal 102 determines that the second terminal 102 successfully accesses the target node according to successfully sending an RRC Connection Re-Configuration RRC connection reconfiguration completion message. Optionally, the second timer is T420.

Step S208: The second terminal 102 sends a second indication message to the first terminal 101.

Optionally, the first terminal 101 receives a second indication message.

In some embodiments, the second terminal 102 determines that access to the target node has failed, and sends a second indication message to the first terminal 101.

In some embodiments, the second indication message is used to instruct the first terminal 101 to trigger RRC reconstruction.

In some embodiments, the second indication message is used to notify the first terminal 101 that the second terminal 102 has failed to access the target node.

In some embodiments, the name of the second indication information is not limited, and it may be, for example, an RRC reestablishment instruction.

In some embodiments, the second terminal 102 sends NotificationMessageSidelink sidelink notification information, and the NotificationMessageSidelink carries or includes the second indication information. Optionally, the first terminal 101 receives the NotificationMessageSidelink to obtain the second indication information.

In some embodiments, the implementation method of the second terminal 102 determining that the access to the target node fails may be: if the second timer times out, it is determined that the second terminal 102 has failed to access the target node.

Step S209: the first terminal 101 stops the first timer.

Optionally, in response to receiving the first indication information sent by the second terminal 102, the first terminal 101 executes step S209.

Optionally, the first terminal 101 executes step S209 in response to triggering RRC reconstruction.

Step S210: The first terminal 101 triggers RRC reconstruction.

Optionally, the first terminal 101 determines that the target node identifier in the first path switching command is inconsistent with the target node identifier in the path change indication, and executes step S210.

Optionally, if the first terminal 101 determines that the first timer has timed out, step S210 is performed. Optionally, the first path switching command includes the duration of the first timer. This provides a configuration method for the duration of the first timer. Optionally, the first terminal 101 determines whether the first timer has timed out according to the duration of the first timer.

Optionally, in response to receiving the second indication information, the first terminal 101 executes step S210.

By adopting the above communication method, in the process of the first terminal and the second terminal changing the path together, keeping the first terminal and the second terminal connected can reduce signaling consumption and avoid service interruption of the first terminal, thereby achieving the purpose of the first terminal and the second terminal changing the path to the target node together.

The communication method involved in the embodiment of the present disclosure may include at least one of steps S201 to S210. For example, step S205 may be implemented as an independent embodiment, and step S204 and step S205 may be implemented as independent embodiments, but are not limited thereto.

In some embodiments, step S201 and step S202 may be executed in an exchanged order or simultaneously, step S203 and step S204 may be executed in an exchanged order or simultaneously, and step S205 and step S206 may be executed in an exchanged order or simultaneously.

In some embodiments, steps S201 to S204 and S206 to S210 are optional, and one or more of these steps may be omitted or replaced in different embodiments.

In some embodiments, steps S201 to S203 and S205 to S210 are optional, and one or more of these steps may be omitted or replaced in different embodiments.

In some embodiments, reference may be made to other optional implementations recorded before or after the description corresponding to FIG. 2 .

FIG3a is a flow chart of a communication method according to an embodiment of the present disclosure. As shown in FIG3a, the present disclosure embodiment relates to a communication method, which is executed by the first terminal 101, and the communication method includes:

Step S3101: Obtain a first path switching command.

The optional implementation of step S3101 can refer to the optional implementation of step S201 in FIG. 2 and other related parts in the embodiment involved in FIG. 2 , which will not be described in detail here.

In some embodiments, the first terminal 101 receives a first path switching command sent by a network device, but is not limited thereto, and may also receive a first path switching command sent by other entities.

In some embodiments, the first terminal 101 obtains a first path switching command specified by a protocol.

In some embodiments, the first terminal 101 obtains a first path switching command from an upper layer(s).

In some embodiments, the first terminal 101 performs processing to obtain a first path switching command.

In some embodiments, step S3101 is omitted, and the first terminal 101 autonomously implements the function indicated by the first path switching command, or the above function is default or acquiescent.

Step S3102, receiving a notification message.

The optional implementation of step S3102 can refer to the optional implementation of step S204 in FIG. 2 and other related parts in the embodiment involved in FIG. 2 , which will not be described in detail here.

In some embodiments, the first terminal 101 receives a notification message sent by the second terminal 102, but is not limited thereto and may also receive a notification message sent by other entities.

In some embodiments, the first terminal 101 obtains a notification message specified by a protocol.

In some embodiments, the first terminal 101 obtains a notification message from an upper layer(s).

In some embodiments, the first terminal 101 performs processing to obtain a notification message.

In some embodiments, step S3102 is omitted, and the first terminal 101 autonomously implements the function indicated by the notification message, or the above function is default or default.

In some embodiments, the notification message is sent to the first terminal 101 when the second terminal 102 initiates access to the target node. Optionally, the notification message indicates that the second terminal 102 initiates access to the target node.

Step S3103, performing path switching.

The optional implementation of step S3103 can refer to the optional implementation of step S205 in FIG. 2 and other related parts in the embodiment involved in FIG. 2 , which will not be described in detail here.

Step S3104, start the first timer.

The optional implementation of step S3104 can refer to the optional implementation of step S206 in FIG. 2 and other related parts in the embodiment involved in FIG. 2 , which will not be described in detail here.

Step S3105, stop the first timer

The optional implementation of step S3105 can refer to the optional implementation of step S209 in FIG. 2 and other related parts in the embodiment involved in FIG. 2 , which will not be described in detail here.

The communication method involved in the embodiment of the present disclosure may include at least one of steps S3101 to S3105. For example, step S3103 may be implemented as an independent embodiment, step S3102 and step S3103 may be implemented as independent embodiments, and step S3101, step S3102 and step S3103 may be implemented as independent embodiments, but are not limited thereto.

In some embodiments, step S3101 and step S3102 may be performed simultaneously.

In some embodiments, step S3101, step S3102, step S3104, and step S3105 are optional, and one or more of these steps may be omitted or replaced in different embodiments.

In some embodiments, step S3101, step S3103, step S3104, and step S3105 are optional, and one or more of these steps may be omitted or replaced in different embodiments.

FIG3b is a flow chart of a communication method according to an embodiment of the present disclosure. As shown in FIG3b, the present disclosure embodiment relates to a communication method, which is executed by the first terminal 101, and the communication method includes:

Step S3201, receiving a notification message.

The optional implementation of step S3201 can refer to step S204 of FIG. 2 , the optional implementation of step S3102 of FIG. 3 a , and other related parts in the embodiments involved in FIG. 2 and FIG. 3 a , which will not be described in detail here.

Step S3202, determine whether to perform path switching or trigger RRC reconstruction.

The optional implementation of step S3202 can refer to the optional implementation of step S205 and step S210 in FIG. 2 , as well as other related parts in the embodiment involved in FIG. 2 , which will not be described in detail here.

Step S3203, perform path switching.

The optional implementation of step S3203 can refer to the optional implementation of step S205 in Figure 2, the optional implementation of step S3103 in Figure 3a, and other related parts in the embodiments involved in Figures 2 and 3a, which will not be repeated here.

Step S3204, trigger RRC reestablishment

The optional implementation of step S3204 can refer to the optional implementation of step S210 in FIG. 2 and other related parts in the embodiment involved in FIG. 2 , which will not be described in detail here.

The communication method involved in the embodiment of the present disclosure may include at least one of step S3201 to step S3204. For example, step S3203 may be implemented as an independent embodiment, step S3204 may be implemented as an independent embodiment, step S3201 and step S3203 may be implemented as independent embodiments, and steps S3201 to S3203 may be implemented as independent embodiments, but are not limited thereto.

In some embodiments, step S3201 and step S3202 may be performed simultaneously.

In some embodiments, step S3201, step S3202, and step S3203 are optional, and one or more of these steps may be omitted or replaced in different embodiments.

In some embodiments, step S3201, step S3202, and step S3204 are optional, and one or more of these steps may be omitted or replaced in different embodiments.

In the embodiment of the present disclosure, step S3202 may be combined with step S3103 of FIG. 3 a , and step S3204 may be combined with step S3105 of FIG. 3 a , but the present invention is not limited thereto.

FIG3c is a flow chart of a communication method according to an embodiment of the present disclosure. As shown in FIG3b, the present disclosure embodiment relates to a communication method, which is executed by the first terminal 101, and the communication method includes:

Step S3301, receiving a notification message.

The optional implementation of step S3301 can refer to the optional implementation of step S204 in Figure 2, the optional implementation of step S3102 in Figure 3a, and other related parts in the embodiments involved in Figures 2 and 3a, which will not be repeated here.

Step S3302, performing path switching.

The optional implementation of step S3302 can refer to the optional implementation of step S205 in Figure 2, the optional implementation of step S3103 in Figure 3a, and other related parts in the embodiments involved in Figures 2 and 3a, which will not be repeated here.

The communication method involved in the embodiment of the present disclosure may include at least one of step S3301 and step S3302. For example, step S3302 may be implemented as an independent embodiment.

In some embodiments, step S3301 is optional and may be omitted or replaced in different embodiments.

In the embodiment of the present disclosure, step S3302 can be combined with step S3104 of FIG. 3a , and step S3302 can be combined with step S3202 of FIG. 3b , but the present invention is not limited thereto.

FIG3d is a flow chart of a communication method according to an embodiment of the present disclosure. As shown in FIG3d, the embodiment of the present disclosure relates to a communication method, which is executed by the first terminal 101, and the communication method includes:

Step S3401, receiving a notification message.

The optional implementation of step S3401 can refer to the optional implementation of step S204 in Figure 2, the optional implementation of step S3102 in Figure 3a, and other related parts in the embodiments involved in Figures 2 and 3a, which will not be repeated here.

Step S3402, trigger RRC reconstruction.

The optional implementation of step S3402 can refer to the optional implementation of step S210 in FIG. 2 and other related parts in the embodiment involved in FIG. 2 , which will not be described in detail here.

The communication method involved in the embodiment of the present disclosure may include at least one of step S3401 and step S3402. For example, step S3402 may be implemented as an independent embodiment.

In some embodiments, step S3401 is optional and may be omitted or replaced in different embodiments.

In the embodiment of the present disclosure, step S3402 may be combined with step S3202 of FIG. 3 b , but is not limited thereto.

FIG4a is a flow chart of a communication method according to an embodiment of the present disclosure. As shown in FIG4a, the present disclosure embodiment relates to a communication method, which is executed by the second terminal 102, and the communication method includes:

Step S4101: receiving a second path switching command.

The optional implementation of step S4101 can refer to the optional implementation of step S202 in FIG. 2 and other related parts in the embodiment involved in FIG. 2 , which will not be described in detail here.

In some embodiments, the second terminal 102 receives the second path switching command sent by the network device, but is not limited thereto, and may also receive the second path switching command sent by other entities.

In some embodiments, the second terminal 102 obtains a second path switching command specified by the protocol.

In some embodiments, the second terminal 102 obtains a second path switching command from an upper layer(s).

In some embodiments, the second terminal 102 performs processing to obtain a second path switching command.

In some embodiments, step S4101 is omitted, and the second terminal 102 autonomously implements the function indicated by the second path switching command, or the above function is default or acquiescent.

Step S4102: initiate access to the target node.

The optional implementation of step S4102 can refer to the optional implementation of step S203 in FIG. 2 and other related parts in the embodiment involved in FIG. 2 , which will not be described in detail here.

Step S4103, sending a notification message.

The optional implementation of step S4103 can refer to the optional implementation of step S204 in FIG. 2 and other related parts in the embodiment involved in FIG. 2 , which will not be described in detail here.

In some embodiments, the second terminal 102 sends a notification message to the first terminal 101, but is not limited thereto and may also send a notification message to other entities.

Optionally, the notification message is used for the first terminal 101 to change the path or trigger RRC reestablishment. The optional implementation method thereof can refer to the optional implementation methods of steps S205 to S210 in FIG2 and other related parts in the embodiment involved in FIG2 , which will not be described in detail here.

Subsequently, either step S4104 or step S4105 is executed.

Step S4104, sending a first indication message.

The optional implementation of step S4104 can refer to the optional implementation of step S207 in FIG. 2 and other related parts in the embodiment involved in FIG. 2 , which will not be described in detail here.

In some embodiments, the second terminal 102 sends the first indication message to the first terminal 101, but is not limited thereto, and the first indication message may also be sent to other entities.

Optionally, the first indication message is used to stop the first timer of the first terminal 101. For its optional implementation, please refer to the optional implementation of step S209 in FIG2 and other related parts in the embodiment involved in FIG2, which will not be described in detail here.

Step S4105: Send a second instruction message

The optional implementation of step S4105 can refer to the optional implementation of step S208 in FIG. 2 and other related parts in the embodiment involved in FIG. 2 , which will not be described in detail here.

In some embodiments, the second terminal 102 sends the second indication message to the first terminal 101, but is not limited thereto, and the second indication message may also be sent to other entities.

Optionally, the second indication message is used to trigger RRC reestablishment by the first terminal 101. For its optional implementation, please refer to the optional implementation of step S210 in FIG2 and other related parts in the embodiment involved in FIG2, which will not be described in detail here.

The communication method involved in the embodiment of the present disclosure may include at least one of step S4101 to step S4105. For example, step S4103 may be implemented as an independent embodiment, and step S4101 and step S4103 may be implemented as independent embodiments. Steps S4101 to S4103 may be implemented as independent embodiments, but are not limited thereto.

In some embodiments, step S4102 and step S4103 may be executed in an interchangeable order or simultaneously.

In some embodiments, step S4101, step S4102, step S4104, and step S4105 are optional, and one or more of these steps may be omitted or replaced in different embodiments.

FIG4b is a flow chart of a communication method according to an embodiment of the present disclosure. As shown in FIG4b, the present disclosure embodiment relates to a communication method, which is executed by the second terminal 102, and the communication method includes:

Step S4201: receiving a second path switching command.

The optional implementation of step S4201 can refer to step S202 of FIG. 2 , the optional implementation of step S4101 of FIG. 4 a , and other related parts in the embodiments involved in FIG. 2 and FIG. 4 a , which will not be described in detail here.

Step S4202, sending a notification message.

For the optional implementation of step S4202, reference may be made to the optional implementation of step S204 in FIG. 2, step S4103 in FIG. 4a, and other related parts in the embodiments involved in FIG. 2 and FIG. 4a, which will not be described in detail here.

The communication method involved in the embodiment of the present disclosure may include at least one of step S4201 to step S4202. For example, step S4202 may be implemented as an independent embodiment, but is not limited thereto.

In some embodiments, step S4201 is optional and may be omitted or replaced in different embodiments.

In the embodiment of the present disclosure, step S4202 may be combined with step S4104 or S4105 of FIG. 4 a , but is not limited thereto.

FIG5a is a schematic diagram of a communication method according to an embodiment of the present disclosure. As shown in FIG5a, the embodiment of the present disclosure relates to a communication method, and the method includes:

Step S5101: A first terminal receives a notification message sent by a second terminal, where the notification message indicates that the second terminal initiates access to a target node.

The optional implementation of step S5101 can refer to the optional implementation of step S204 in Figure 2, step S3102 in Figure 3a, step S4103 in Figure 4a, and other related parts in the embodiments involved in Figures 2, 3a, and 4a, which will not be repeated here.

Step S5102: perform path switching.

The optional implementation of step S5102 can refer to the optional implementation of step S205 in Figure 2, step S3103 in Figure 3a, step S4103 in Figure 4a, and other related parts in the embodiments involved in Figures 2, 3a, and 4a, which will not be repeated here.

In some embodiments, the above method may include the method described in the above embodiments of the communication system side, the first terminal side, the second terminal side, the network device side, etc., which will not be repeated here.

FIG5b is a schematic diagram of a communication method according to an embodiment of the present disclosure. As shown in FIG5b, the embodiment of the present disclosure relates to a communication method, and the method includes:

Step S5201: The second terminal receives a second path switching command sent by a network device and initiates access to a target node.

The optional implementation of step S5201 can refer to the optional implementation of step S202 in FIG. 2 and other related parts in the embodiment involved in FIG. 2 , which will not be described in detail here.

Step S5202: Send a notification message to the first terminal, where the notification message indicates that the second terminal initiates access to the target node.

The optional implementation of step S5202 can refer to the optional implementation of step S204 in Figure 2, step S3102 in Figure 3a, step S4103 in Figure 4a, and other related parts in the embodiments involved in Figures 2, 3a, and 4a, which will not be repeated here.

In some embodiments, the above method may include the method described in the above embodiments of the communication system side, the first terminal side, the second terminal side, the network device side, etc., which will not be repeated here.

The present disclosure also provides an interactive mode of a communication method, wherein the remote UE maintains connection with the network through the relay UE.

The remote UE is used to perform the following processing:

1. Receive a first set of switching commands sent by the network, which carries a first configuration, and the first configuration is a configuration used after the path switching. Store the received first set of switching commands, and use the first configuration when determining to perform group switching.

As an embodiment, the first group of switching commands may be reconfigurationwithsync or pathswitch signaling.

As an embodiment, the first configuration used may include any one of the following: bearer configuration (PDCP, RLC or SL-RLC), MAC configuration and random access configuration, wherein the random access configuration is used to switch from a relay UE to a cell.

During the group handover process, the remote UE maintains the connection with the serving relay UE.

2. Based on 1, a notification message sent by the relay UE is received, which carries a path switching indication, and it is determined to perform group switching.

As an embodiment, the relay UE is a service relay UE connected to a remote UE.

As an embodiment, the path switching indication may be carried by NotificationMessageSidelink.

3. Based on 1 and/or 2, further, the path switching target node identifier carried in the notification message sent by the relay UE is consistent with the target node identifier in the group switching command, and it is determined to perform group switching. The group switching command may carry the target node identifier.

As an embodiment, when the target node is a cell, the identifier may be a cell identifier, and when the target node is a relay UE, the identifier may be a relay UE identifier.

4. Based on 1 and/or 2, further, if the path switching target node identifier carried in the notification message of the relay UE is inconsistent with the target node identifier in the group switching command, it is determined to trigger RRC reconstruction. The group switching command may carry the target node identifier.

5. Based on 2, start the first timer, and if the first timer times out, trigger RRC reestablishment. The first timer duration is carried in the first group of handover commands.

6. Based on 5, receive a first indication sent by the relay UE, indicating that the access is successful, and stop the first timer.

7. Based on 5, receive a second indication sent by the relay UE, indicating access failure, stop the first timer, and trigger RRC reestablishment.

The relay UE is used to perform the following processing:

1. Receive a second group of path switching commands sent by the network, the group switching commands carrying the first configuration and the identifier of the target node, the first configuration being the configuration used after the path switching. Initiate access to the target node and start a second timer. Send a notification message to the connected remote UE, carrying the path switching indication.

As an embodiment, the second group of path switching commands may carry one or more remote UE identifiers.

As an embodiment, the second group of path switching commands may be reconfigurationwithsync or pathswitch signaling.

As an embodiment, when the target node is a cell, the identifier may be a cell identifier, and the target node is a relay UE. When the identifier is a relay UE identifier, the identifier may be a relay UE identifier.

2. Based on 1, the second group of path switching commands may carry a remote UE identifier, and a path switching indication is sent to a remote UE identified by the remote UE identifier.

As an embodiment, if there is a remote UE whose identifier is not in the second group of path switch commands, the relay UE sends a traditional NotificationMessageSidelink message to the remote UE, indicating HO. For the remote UE whose identifier is in the second group of path switch commands, a path switch indication is sent.

3. Based on 1, the path switching indication carries the target node identifier.

4. Based on 1, initiate access to the target node. If the access is successful, send a first indication to the remote UE and stop the second timer.

As an embodiment, if the target node is a cell, access success is determined based on successful completion of the random access process. If the target node is a relay UE, access success is determined based on successful sending of an RRC reconfiguration complete message.

5. Based on 1, if the second timer times out, it is determined that the access has failed, and a second indication is sent to the remote UE.

As an embodiment, if the target node is a cell, the second timer may be T304 timeout. If the target node is a relay UE, the second timer may be T420.

In the embodiments of the present disclosure, part or all of the steps and their optional implementations may be arbitrarily combined with part or all of the steps in other embodiments, or may be arbitrarily combined with optional implementations of other embodiments.

The embodiments of the present disclosure also propose a device for implementing any of the above methods, for example, a device is proposed, the above device includes a unit or module for implementing each step performed by the first terminal in any of the above communication methods. For another example, another device is also proposed, including a unit or module for implementing each step performed by the second terminal in any of the above communication methods.

It should be understood that the division of the units or modules in the above device is only a division of logical functions, and in actual implementation, they can be fully or partially integrated into one physical entity, or they can be physically separated. In addition, the units or modules in the device can be implemented in the form of a processor calling software: for example, the device includes a processor, the processor is connected to a memory, and instructions are stored in the memory. The processor calls the instructions stored in the memory to implement any of the above methods or implement the functions of the units or modules of the above device, wherein the processor is, for example, a general-purpose processor, such as a central processing unit (CPU) or a microprocessor, and the memory is a memory inside the device or a memory outside the device. Alternatively, the units or modules in the device can be implemented in the form of hardware circuits, and the functions of some or all of the units or modules can be realized by designing the hardware circuits. The above-mentioned hardware circuits can be understood as one or more processors; for example, in one implementation, the above-mentioned hardware circuit is an application-specific integrated circuit (ASIC), and the functions of some or all of the above units or modules are realized by designing the logical relationship of the components in the circuit; for another example, in another implementation, the above-mentioned hardware circuit can be implemented by a programmable logic device (PLD). Taking the Field Programmable Gate Array (FPGA) as an example, it can include a large number of logic gate circuits, and the connection relationship between the logic gate circuits is configured through configuration files, so as to realize the functions of some or all of the above units or modules. All units or modules of the above devices can be implemented in the form of a processor calling software, or in the form of hardware circuits, or in part by a processor calling software, and the rest by Implemented in the form of hardware circuit.

In the disclosed embodiments, the processor is a circuit with signal processing capability. In one implementation, the processor may be a circuit with instruction reading and running capability, such as a central processing unit (CPU), a microprocessor, a graphics processing unit (GPU) (which may be understood as a microprocessor), or a digital signal processor (DSP); in another implementation, the processor may implement certain functions through the logical relationship of a hardware circuit, and the logical relationship of the above hardware circuit may be fixed or reconfigurable, such as a hardware circuit implemented by an application-specific integrated circuit (ASIC) or a programmable logic device (PLD), such as an FPGA. In a reconfigurable hardware circuit, the process of the processor loading a configuration document to implement the hardware circuit configuration may be understood as the process of the processor loading instructions to implement the functions of some or all of the above units or modules. In addition, it can also be a hardware circuit designed for artificial intelligence, which can be understood as ASIC, such as Neural Network Processing Unit (NPU), Tensor Processing Unit (TPU), Deep Learning Processing Unit (DPU), etc.

FIG6a is a schematic diagram of the structure of a terminal proposed in an embodiment of the present disclosure. As shown in FIG6a, the terminal 6100 may include at least one of a receiving module 6101 and a processing module 6102. In some embodiments, the receiving module 6101 is used to receive a notification message sent by a second terminal, and the notification message indicates that the second terminal initiates access to a target node. The processing module 6102 is used to perform path switching.

Optionally, the receiving module 6101 is used to execute at least one of the communication steps such as sending and/or receiving executed by the first terminal 101 in any of the above communication methods (for example, step S201, step S204, step S207, step S208, but not limited thereto), which will not be described in detail here. Optionally, the processing module 6102 is used to execute at least one of the other steps (for example, step S205, step S206, step S209, step S210, but not limited thereto) executed by the first terminal 101 in any of the above communication methods, which will not be described in detail here.

FIG6b is a schematic diagram of the structure of the terminal proposed in an embodiment of the present disclosure. As shown in FIG6b, the terminal 6200 may include: at least one of a transceiver module 6201, a processing module 6202, etc. In some embodiments, the transceiver module 6201 is used to receive a second path switching command sent by a network device; send a notification message to the first terminal, the notification message indicating that the second terminal initiates access to the target node. The processing module 6202 is used to initiate access to the target node.

Optionally, the transceiver module 6201 is used to execute at least one of the communication steps such as sending and/or receiving (such as step S204, step S207, step S208, but not limited thereto) executed by the second terminal 102 in any of the above communication methods, which will not be described in detail here. Optionally, the processing module 6202 is used to execute at least one of the other steps (such as step S203, but not limited thereto) executed by the second terminal 102 in any of the above communication methods, which will not be described in detail here.

In some embodiments, the transceiver module may include a sending module and/or a receiving module, and the sending module and the receiving module may be separate or integrated. Optionally, the transceiver module may be interchangeable with the transceiver.

In some embodiments, the processing module may be a single module or may include multiple submodules. Optionally, the multiple submodules respectively execute all or part of the steps required to be executed by the processing module. Optionally, the processing module may be interchangeable with the processor. Change.

FIG7a is a schematic diagram of the structure of a communication device 7100 proposed in an embodiment of the present disclosure. The communication device 7100 may be a network device (e.g., an access network device, a core network device, etc.), or a terminal (e.g., a user device, etc.), or a chip, a chip system, or a processor that supports a network device to implement any of the above methods, or a chip, a chip system, or a processor that supports a terminal to implement any of the above communication methods. The communication device 7100 may be used to implement the method described in the above communication method embodiment, and the details may refer to the description in the above communication method embodiment.

As shown in FIG. 7a , the communication device 7100 includes one or more processors 7101. The processor 7101 may be a general-purpose processor or a dedicated processor, for example, a baseband processor or a central processing unit. The baseband processor may be used to process the communication protocol and the communication data, and the central processing unit may be used to control the communication device (such as a base station, a baseband chip, a terminal device, a terminal device chip, a DU or a CU, etc.), execute a program, and process the data of the program. The communication device 7100 is used to execute any of the above methods.

In some embodiments, the communication device 7100 further includes one or more memories 7102 for storing instructions. Optionally, all or part of the memory 7102 may also be outside the communication device 7100.

In some embodiments, the communication device 7100 further includes one or more transceivers 7103. When the communication device 7100 includes one or more transceivers 7103, the transceiver 7103 performs at least one of the communication steps such as sending and/or receiving in the above method (for example, step S201, step S202, step S204, step S207, step S208, but not limited thereto), and the processor 7101 performs at least one of the other steps (for example, step S203, step S205, step S206, step S209, step S210, but not limited thereto).

In some embodiments, the transceiver may include a receiver and/or a transmitter, and the receiver and the transmitter may be separate or integrated. Optionally, the terms such as transceiver, transceiver unit, transceiver, transceiver circuit, etc. may be replaced with each other, the terms such as transmitter, transmission unit, transmitter, transmission circuit, etc. may be replaced with each other, and the terms such as receiver, receiving unit, receiver, receiving circuit, etc. may be replaced with each other.

In some embodiments, the communication device 7100 may include one or more interface circuits 7104. Optionally, the interface circuit 7104 is connected to the memory 7102, and the interface circuit 7104 may be used to receive signals from the memory 7102 or other devices, and may be used to send signals to the memory 7102 or other devices. For example, the interface circuit 7104 may read instructions stored in the memory 7102 and send the instructions to the processor 7101.

The communication device 7100 described in the above embodiments may be a network device or a terminal, but the scope of the communication device 7100 described in the present disclosure is not limited thereto, and the structure of the communication device 7100 may not be limited by FIG. 7a. The communication device may be an independent device or may be part of a larger device. For example, the communication device may be: 1) an independent integrated circuit IC, or a chip, or a chip system or subsystem; (2) a collection of one or more ICs, optionally, the above IC collection may also include a storage component for storing data and programs; (3) an ASIC, such as a modem; (4) a module that can be embedded in other devices; (5) a receiver, a terminal device, an intelligent terminal device, a cellular phone, a wireless device, a handheld device, a mobile unit, a vehicle-mounted device, a network device, a cloud device, an artificial intelligence device, etc.; (6) others, etc.

Fig. 7b is a schematic diagram of the structure of a chip 7200 provided in an embodiment of the present disclosure. In the case where the communication device 7100 may be a chip or a chip system, reference may be made to the schematic diagram of the structure of the chip 7200 shown in Fig. 7b, but the present invention is not limited thereto.

The chip 7200 includes one or more processors 7201, and the chip 7200 is used to execute any of the above methods.

In some embodiments, the chip 7200 further includes one or more interface circuits 7202. Optionally, the interface circuit 7202 is connected to the memory 7203. The interface circuit 7202 can be used to receive signals from the memory 7203 or other devices, and the interface circuit 7202 can be used to send signals to the memory 7203 or other devices. For example, the interface circuit 7202 can read instructions stored in the memory 7203 and send the instructions to the processor 7201.

In some embodiments, the interface circuit 7202 executes at least one of the communication steps such as sending and/or receiving in the above method (for example, step S201, step S202, step S204, step S207, step S208, but not limited to these), and the processor 7201 executes at least one of the other steps (for example, step S203, step S205, step S206, step S209, step S210, but not limited to these).

In some embodiments, terms such as interface circuit, interface, transceiver pin, and transceiver may be used interchangeably.

In some embodiments, the chip 7200 further includes one or more memories 7203 for storing instructions. Optionally, all or part of the memory 7203 may be outside the chip 7200.

The present disclosure also proposes a storage medium, on which instructions are stored, and when the instructions are executed on the communication device 7100, the communication device 7100 executes any of the above methods. Optionally, the storage medium is an electronic storage medium. Optionally, the storage medium is a computer-readable storage medium, but is not limited to this, and it can also be a storage medium readable by other devices. Optionally, the storage medium can be a non-transitory storage medium, but is not limited to this, and it can also be a temporary storage medium.

The present disclosure also proposes a program product, which, when executed by the communication device 7100, enables the communication device 7100 to execute any of the above methods. Optionally, the program product is a computer program product.

The present disclosure also proposes a computer program, which, when executed on a computer, causes the computer to execute any one of the above methods.

Claims (27)

A communication method, performed by a first terminal, characterized in that the method comprises: receiving a notification message sent by a second terminal, where the notification message indicates that the second terminal initiates access to a target node; Switch the path. The method according to claim 1, characterized in that The first terminal has a first path switching command; Before switching paths, include: Determining that the notification message includes a path change indication; It is determined that the target node identifier in the first path switching command is consistent with the target node identifier in the path change indication. The method according to claim 2, characterized in that the method further comprises: It is determined that the target node identifier in the first path switching command is inconsistent with the target node identifier in the path change indication, and RRC reconstruction is triggered. The method according to claim 2 or 3, characterized in that The target node identifier is a cell identifier or a relay terminal identifier. The method according to claim 1 or 2, characterized in that The first path switching command on the first terminal includes a first configuration, wherein the first configuration includes at least one of a bearer configuration, a MAC configuration, and a random access configuration; The performing path switching includes: Perform path switching according to the first configuration and start a first timer. The method according to claim 5, characterized in that the method further comprises: Determine that the first timer has timed out, and trigger RRC reconstruction. The method according to claim 6, characterized in that The first path switching command also includes the duration of the first timer; The method further comprises: Determine whether the first timer has timed out according to the duration of the first timer. The method according to any one of claims 5 to 7, characterized in that the method further comprises: receiving a first indication message sent by the second terminal, wherein the first indication message indicates that the second terminal successfully accesses the The target node; Stop the first timer. The method according to any one of claims 5 to 7, characterized in that the method further comprises: receiving a second indication message sent by the second terminal, where the second indication message indicates that the second terminal fails to access the target node; Trigger RRC re-establishment. The method according to claim 9, characterized in that the method further comprises: Stop the first timer. The method according to any one of claims 2 to 10, characterized in that the method further comprises: Receiving the first path switching command sent by the network device; The first path switching command is stored. The method according to any one of claims 1 to 11, characterized in that The path switching is group path switching; During the group path switching process, the first terminal maintains connection with the second terminal. A communication method, performed by a second terminal, characterized in that the method comprises: receiving a second path switching command sent by the network device, and initiating access to the target node; A notification message is sent to the first terminal, where the notification message indicates that the second terminal initiates access to the target node. The method according to claim 13, characterized in that The second path switching command includes a target node identifier, and the target node is determined according to the target node identifier; and/or, The second path switching command includes a first terminal identifier, and the first terminal is determined according to the first terminal identifier. The method according to claim 14, characterized in that The notification message includes a path change indication, and the path change indication includes the target node identifier, and the target node identifier is used by the first terminal to determine to perform a path switch or trigger an RRC reconstruction. The method according to any one of claims 13 to 15, characterized in that the second path switching command includes a first configuration, wherein the first configuration includes at least one of a bearer configuration, a MAC configuration, and a random access configuration; The initiating access to the target node includes: Access is initiated to the target node according to the first configuration, and a second timer is started. The method according to claim 16, characterized in that the method further comprises: Determining that the target node is successfully accessed, and stopping the second timer; A first indication message is sent to the first terminal, where the first indication message is used to instruct the first terminal to stop a first timer. The method according to claim 17, characterized in that The target node identifier of the target node is a cell identifier; The determining that the target node is successfully accessed includes: Successful access to the target node is determined based on successful completion of the random access process. The method according to claim 17, characterized in that The target node identifier of the target node is a relay terminal identifier; The determining that the target node is successfully accessed includes: Successful access to the target node is determined based on successful sending of the RRC connection reconfiguration complete message. The method according to claim 16, characterized in that the method further comprises: Determine that access to the target node fails, and send a second indication message to the first terminal, where the second indication message is used to instruct the first terminal to trigger RRC reconstruction. The method according to claim 20, wherein the determining that access to the target node fails comprises: When the second timer times out, it is determined that access to the target node fails. The method according to any one of claims 16 to 21, characterized in that The second timer is T304 or T420. A first terminal, characterized in that the first terminal comprises: A receiving module, configured to receive a notification message sent by a second terminal, wherein the notification message indicates that the second terminal initiates access to a target node; A processing module is used for the first terminal to perform path switching. A second terminal, characterized in that the second terminal comprises: The transceiver module is used to receive a second path switching command sent by a network device, initiate access to a target node, and send a notification message to the first terminal, wherein the notification message indicates that the second terminal initiates access to the target node. A terminal, characterized by comprising: one or more processors; The terminal is used to execute the communication method described in any one of claims 1 to 22. A communication system, characterized in that it includes a first terminal and a second terminal, wherein the first terminal is configured to implement the communication method described in any one of claims 1-12, and the second terminal is configured to implement the communication method described in any one of claims 13-22. A storage medium storing instructions, characterized in that when the instructions are executed on a communication device, the communication device executes the communication method described in any one of claims 1 to 22.