WO2022012426A1

WO2022012426A1 - Method and apparatus for switching uu path to direct communication path, and candidate relay ue indication method and apparatus, storage medium, terminal and base station

Info

Publication number: WO2022012426A1
Application number: PCT/CN2021/105429
Authority: WO
Inventors: 曹春燕; 刘星
Original assignee: 展讯半导体(南京)有限公司
Priority date: 2020-07-16
Filing date: 2021-07-09
Publication date: 2022-01-20
Also published as: CN113950110B; CN113950110A

Abstract

A method and apparatus for switching a Uu path to a direct communication path, and a candidate relay UE indication method and apparatus, a storage medium, a terminal and a base station. The method for switching a Uu path to a direct communication path comprises: sending a first message, wherein the first message comprises position information of an edge UE; receiving a second message, wherein the second message comprises an identifier of one or more candidate relay UEs, and the one or more candidate relay UEs are determined according to the position information of the edge UE; and selecting a preferred relay UE from among the one or more candidate relay UEs, and establishing a direct communication path with the preferred relay UE. By means of the present invention, the path switching delay can be greatly reduced.

Description

Method, device, storage medium, terminal, and base station for switching from Uu path to direct communication path and for indicating candidate relay UE

This application is required to be submitted to the China Patent Office on July 16, 2020, the application number is 202010687605.8, and the title of the invention is "Uu path to direct communication path handover and candidate relay UE indication method, device, storage medium, terminal, base station" in China Priority to the patent application, the entire contents of which are incorporated herein by reference.

technical field

The present invention relates to the field of communication technologies, and in particular to a method, device, storage medium, terminal, and base station for switching from a Uu path to a direct communication path and indicating a candidate relay UE.

Background technique

In the protocol version 12 (Release 12, referred to as R12), Long Term Evolution (Long Term Evolution, referred to as LTE) introduced the Proximity-based Services (Proximity-based Services, referred to as ProSe) direct communication mode. User Equipment (UE) A and UE B (which may be multiple UEs) can communicate directly through a PC5 interface, which is a direct interface between UEs. The communication interface between the UE and the base station is called the Uu interface (where U represents the user network interface, User to Network interface; u represents the universal, Universal).

The Service and System Aspects (SA) Working Group (WG) 2 of the 3rd Generation Partnership Project (3GPP) studied the system architecture of ProSe direct communication and introduced A communication architecture in which the UE is connected to the network through a relay (UE-to-network Relay). This communication architecture enables UEs (such as UE A) that cannot communicate directly with the base station to relay service data through other UEs (such as UE B) to achieve direct communication. At this time, UE B is the relay UE (Relay UE) .

3GPP also introduced a communication architecture in which the UE is connected to the UE through a relay (UE-to-UE Relay). This communication architecture enables UE A and UE B that cannot communicate directly through the PC5 link to relay service data through other UEs (ie, relay UEs) to achieve direct communication.

A UE that communicates through a relay UE is generally referred to as an edge user (Remote UE, hereinafter referred to as an edge UE). Regardless of the communication architecture in which the UE is connected to the network through the relay or the UE is connected to the UE through the relay, the edge UE that wants to communicate through the relay UE needs to perform the handover from the Uu path to the PC5 path.

According to the prior art, when the edge UE performs the process of converting the Uu path to the PC5 path, the edge UE needs to first perform a relay discovery (Relay discovery) process to discover available candidate relay UEs around. Then measure the reference signal received power (Reference Signal Receiving Power, RSRP for short, which is used to measure link quality) with the candidate relay UE. Then, the edge UE reports the measurement result to the base station, and the base station makes a path switching decision and selects an optimal relay UE. The edge UE is then switched from the source base station to the relay UE, thereby completing the conversion from the Uu path to the PC5 path.

The aforementioned delay of the entire path conversion is very large. Specifically, the edge UE needs to perform measurement and measurement reporting, and the whole process takes a long time. In addition, the time delay between the time when the base station decides to issue the handover result and when the UE performs path switching is relatively large. In addition, the signaling overhead of the relay discovery process performed by the edge UE is relatively large.

SUMMARY OF THE INVENTION

The technical problem solved by the present invention is how to reduce the path switching delay from the Uu path to the direct communication path.

To solve the above technical problem, an embodiment of the present invention provides a method for switching from a Uu path to a direct communication path, including: sending a first message, where the first message includes location information of an edge UE; receiving a second message, wherein , the second message includes the identifiers of one or more candidate relay UEs, and the one or more candidate relay UEs are determined according to the location information of the edge UE; from the one or more candidate relay UEs A preferred relay UE is selected from among the UEs, and a direct communication path is established with the preferred relay UE.

Optionally, the second message further includes a link quality threshold for relay selection.

Optionally, the operation of sending the first message is performed in response to the link quality of the Uu path being lower than a first preset threshold.

Optionally, the first message further includes the link quality of the Uu path.

Optionally, the selecting a preferred relay UE from the one or more candidate relay UEs includes: broadcasting a direct communication request, wherein the direct communication request includes an identifier of the one or more candidate relay UEs ; determining the preferred relay UE according to the responses of the one or more candidate relay UEs.

Optionally, the selecting a preferred relay UE from the one or more candidate relay UEs includes: unicasting a direct communication request to the one or more candidate UEs respectively; The preferred relay UE is determined based on the response of the relay UE.

Optionally, the determining the preferred relay UE according to the responses of the one or more candidate relay UEs includes: when only a response message of a single candidate relay UE is received, measuring and responding to the candidate relay UEs. the link quality between the relay UEs, and determine the responding candidate relay UE as the preferred relay UE according to the measurement result; when receiving response messages from multiple candidate relay UEs, according to the response The link quality between each candidate relay UE of , determines the preferred relay UE.

Optionally, the direct communication request includes a service quality indicator for establishing a direct communication path.

To solve the above technical problem, an embodiment of the present invention further provides a method for indicating a candidate relay UE, including: receiving a first message, where the first message includes location information of an edge UE; according to the location information of the edge UE One or more candidate relay UEs are selected from a preset list of available relay UEs; and a second message is generated and sent based on the one or more candidate relay UEs.

Optionally, the first message is sent when it is determined that the link quality of the Uu path is lower than a first preset threshold, where the Uu path is a communication link between the edge UE and the base station.

Optionally, the first message further includes the link quality of the Uu path.

Optionally, the method for indicating a candidate relay UE further includes: receiving capability reporting information; determining, according to the capability reporting information, whether to add the UE sending the capability reporting information to the preset list of available relay UEs, or , whether to delete the UE that sends the capability reporting information from the preset list of available relay UEs.

Optionally, the preset list of available relay UEs includes location information of each candidate relay UE.

Optionally, the preset list of available relay UEs includes relay UEs of neighboring base stations.

Optionally, the preset list of available relay UEs is updated in real time.

Optionally, the selecting one or more candidate relay UEs from the preset list of available relay UEs according to the location information of the edge UE includes: selecting, in the preset list of available relay UEs, those located in the preset list of available relay UEs. The position of the edge UE is the center of the circle, and the relay UEs within the preset radius are determined as the one or more candidate relay UEs.

Optionally, the preset radius is at least associated with the location information of the edge UE, the transmit power of the relay UE and/or the transmit power of the edge UE.

In order to solve the above technical problem, an embodiment of the present invention further provides an apparatus for switching from a Uu path to a direct communication path, including: a sending module configured to send a first message, wherein the first message includes location information of an edge UE; a receiving module, configured to receive a second message, wherein the second message includes the identifiers of one or more candidate relay UEs, and the one or more candidate relay UEs are determined according to the location information of the edge UEs a handover module, configured to select a preferred relay UE from the one or more candidate relay UEs, and establish a direct communication path with the preferred relay UE.

In order to solve the above technical problem, an embodiment of the present invention further provides a candidate relay UE indication device, including: a receiving module, configured to receive a first message, wherein the first message includes location information of the edge UE; a selection module, is used to select one or more candidate relay UEs from a preset list of available relay UEs according to the location information of the edge UEs; an indication module is used to generate a second message based on the one or more candidate relay UEs and send.

In order to solve the above technical problem, an embodiment of the present invention further provides a storage medium on which a computer program is stored, and the computer program executes the steps of the above method when the computer program is run by a processor.

In order to solve the above technical problem, an embodiment of the present invention further provides a terminal, including the above-mentioned switching device from the Uu path to the direct communication path, or, including a memory and a processor, and the memory stores a memory capable of running on the processor. A computer program, the processor executes the steps of the above method when running the computer program.

In order to solve the above technical problem, an embodiment of the present invention further provides a base station, including the above-mentioned candidate relay UE indicating device, or, including a memory and a processor, and the memory stores a computer program that can run on the processor. , the processor executes the steps of the above method when running the computer program.

Compared with the prior art, the technical solutions of the embodiments of the present invention have the following beneficial effects:

For the edge UE side, an embodiment of the present invention provides a method for switching from a Uu path to a direct communication path, including: sending a first message, wherein the first message includes location information of the edge UE; receiving a second message, wherein, The second message includes the identifiers of one or more candidate relay UEs, the one or more candidate relay UEs are determined according to the location information of the edge UE; from the one or more candidate relay UEs A preferred relay UE is selected from among the preferred relay UEs, and a direct communication path is established with the preferred relay UE.

This embodiment provides a more efficient conversion method from a Uu path to a direct communication path, which can greatly reduce the path conversion delay. Specifically, the first message sent by the edge UE does not carry the link quality measurement result with the surrounding candidate relay UEs, but reports its own position. Correspondingly, the second message sent by the base station directly indicates available candidate relay UEs around the edge UE for selection by the edge UE. Since the edge UE does not need to perform the relay discovery process, it can save the time delay of the three steps of measurement, measurement reporting and base station decision. Further, signaling overhead during path switching can be greatly reduced.

For the base station side, an embodiment of the present invention further provides a method for indicating a candidate relay UE, including: receiving a first message, where the first message includes location information of an edge UE; It is assumed that one or more candidate relay UEs are selected from the list of available relay UEs; a second message is generated and sent based on the one or more candidate relay UEs.

This embodiment provides a more efficient method for indicating a candidate relay UE, which can greatly reduce signaling overhead during path switching. Specifically, the base station maintains a preset list of available relay UEs, and after receiving the first message, selects a suitable candidate relay UE from the list and indicates it to the edge UE. For the base station, there is no need to receive the link quality with each candidate relay UE measured by the edge UE, which makes it possible to reduce signaling overhead. Further, the base station does not need to make a decision based on the link quality measurement result, which makes it possible to reduce the delay.

Description of drawings

1 is a flowchart of a method for switching from a Uu path to a direct communication path according to an embodiment of the present invention;

2 is a schematic structural diagram of a device for switching from a Uu path to a direct communication path according to an embodiment of the present invention;

3 is a flowchart of a method for indicating a candidate relay UE according to an embodiment of the present invention;

FIG. 4 is a schematic structural diagram of an apparatus for indicating a candidate relay UE according to an embodiment of the present invention.

detailed description

As mentioned in the background art, the existing process of executing the path conversion (also referred to as handover) from the Uu path to the PC5 path has a very large delay. Signaling overhead is also large.

Specifically, when an existing edge UE performs path conversion from a Uu path to a PC5 path, a relay discovery process is first performed, and the purpose of this process is for the edge UE to discover surrounding relay UEs.

Relay discovery includes two modes: mode A (model A) and mode B (model B). The principle of mode A is that each relay UE periodically broadcasts relay discovery messages, and surrounding edge UEs that need relay services can find out whether there are relay UEs nearby by simply monitoring the broadcast messages. The principle of mode B is: the edge UE sends a solicitation message (Solicitation message) to the surrounding relay UE, and the relay UE replies a response message (Response message) to the edge UE after receiving it.

In the communication architecture where the UE is connected to the network through the relay, the edge UE is converted from the Uu path to the PC5 path. There are two scenarios in the current protocol: 1. The edge UE and the relay UE are under the same base station, that is, the same cell Intra-cell Uu path to PC5 path conversion; 2. The edge UE and the relay UE are under different base stations, that is, the inter-cell Uu path to PC5 path conversion.

No matter which scenario it is, the steps in the process of performing Uu path to PC5 path conversion in the prior art are as follows:

Step 1: The edge UE initially establishes a connection with the base station and transmits data services through the Uu interface. When the signal quality between the edge UE and the base station deteriorates, the base station will configure the edge UE to perform conversion measurement from the Uu path to the PC5 path through dedicated signaling.

Step 2: After receiving the measurement configuration signaling of the base station, the edge UE performs a relay discovery process, in order to discover available candidate relay UEs around, and measure the RSRP with the candidate relay UE.

Step 3: The edge UE reports the measurement result to the base station, and the report content includes the discovered candidate relay UEs and the RSRP value between them.

Step 4: After receiving the measurement result reported by the edge UE, the base station makes a path switching decision according to the measurement result to select an optimal relay UE, and then notifies the edge UE to perform the path switching.

Step 5: (1) If the relay UE and the edge UE selected by the base station are in the same cell, the edge UE directly initiates the connection establishment process with the relay UE to complete the conversion from the Uu path to the PC5 path; (2) If the base station selects If the relay UE and the edge UE are located in different cells, the source base station where the edge UE is located must first perform a handover request process with the target base station where the relay UE is located; the target base station inquires the relay UE, and if the relay UE confirms the handover request, The target base station then sends a handover confirmation message to the source base station; after receiving the handover confirmation, the source base station notifies the edge UE through reconfiguration signaling, and the edge UE establishes a connection with the relay UE again. So far, the conversion from the Uu path to the PC5 path is completed.

On the other hand, the process of establishing a connection between the edge UE and the relay UE may include four steps:

Step 1: The edge UE sends a direct communication request message to start the PC5 unicast link establishment process. The direct communication request message may include: 1) source user information (source User Info), such as the application layer identification (Identification, ID for short) of the initial UE, that is, the application layer ID of the edge UE; 2) vehicle-to-external information exchange (vehicle). to everything, referred to as V2X) service identifier; 3) target user information (target User Info), such as the application layer ID of the target UE, that is, the application layer ID of the relay UE; 4) security establishment information.

Step 2: After the relay UE receives the direct communication request message, it sends a direct security mode control message to the edge UE to confirm whether there is a security context with the edge UE. security-related processes.

Step 3: The edge UE replies a direct security mode complete message to the relay UE.

Step 4: After receiving the direct security mode, the relay UE sends a direct communication acceptance message to the edge UE, which represents acceptance of the PC5 unicast link establishment process. Wherein, the direct communication request acceptance message may include: 1) source user information (source User Info), such as the application layer ID of the target UE, that is, the application layer ID of the relay UE; 2) the corresponding PC5 quality of service (Quality of Service, QoS for short) parameters; 3) Internet Protocol (Internet Protocol, IP for short) address configuration, etc.

In the prior art, the five steps of executing the Uu path to PC5 path conversion process are very complicated, and the delay of the entire path conversion is relatively large. In particular, the edge UE performs measurement and measurement reporting, and the base station decides to deliver the handover result to the UE to perform path switching, and the delay is relatively large, and the signaling overhead of performing the relay discovery process is relatively large.

In order to make the above objects, features and beneficial effects of the present invention more clearly understood, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a flowchart of a method for switching from a Uu path to a direct communication path according to an embodiment of the present invention.

This embodiment may be performed by the user equipment side, such as performed by the edge UE. By implementing the solution of the embodiment shown in FIG. 1 , the edge UE can switch from the Uu path to the direct communication path. The direct communication path may be a PC5 path, or may be other communication paths capable of directly communicating with other UEs (eg, relay UEs).

In a specific implementation, the method for switching the Uu path to the direct communication path provided in the following steps S101 to S103 can be performed by a chip with a path switching function in the user equipment, or by a baseband chip in the user equipment.

Specifically, referring to FIG. 1 , the method for switching from a Uu path to a direct communication path described in this embodiment may include the following steps:

Step S101, sending a first message, wherein the first message includes location information of edge UEs;

Step S102, receiving a second message, wherein the second message includes the identifiers of one or more candidate relay UEs, and the one or more candidate relay UEs are determined according to the location information of the edge UE;

Step S103: Select a preferred relay UE from the one or more candidate relay UEs, and establish a direct communication path with the preferred relay UE.

In a specific implementation, when the signal quality between the edge UE and the base station deteriorates and the relay UE needs to relay services to the base station, the edge UE may perform step S101 to send a first message to the base station, thereby triggering the base station to perform path switching .

For example, the base station may configure a measurement reporting trigger event for the edge UE in advance, so as to trigger the edge UE to perform step S101. The measurement reporting trigger event may be that the link quality between the edge UE and the base station is lower than the first preset threshold. The first preset threshold may be pre-configured by the base station for the edge UE.

The link quality between the edge UE and the base station can be characterized based on RSRP.

In a specific implementation, the first message may include location information of the edge UE that sends the message, such as a zone identifier (Zone_Identification, Zone_ID for short). For another example, the location information of the edge UE may be the location information determined based on a Global Positioning System (Global Positioning System, GPS for short) that comes with the edge UE.

In a specific implementation, in addition to the position of the edge UE itself, the first message may also include the link quality of the Uu path, so that the base station can further know the actual link condition with the edge UE. For example, the first message may include the actual RSRP value between the edge UE and the base station measured by the edge UE.

Correspondingly, the first message can be understood as a measurement result message, which is used to report the measurement result of the link quality of the Uu path.

In a specific implementation, in response to receiving the first message, the base station may send a second message to the edge UE to instruct the edge UE to perform path switching.

Specifically, the base station may send, according to the location information reported by the edge UE in the first message, the relay UE located near the edge UE and within the optimal communication range to the edge UE through the second message.

For the specific behavior of the base station and the specific content of the second message, reference may be made to the related description in the embodiment shown in FIG. 3 below.

Therefore, by means of direct indication by the base station, the edge UE can know the available candidate relay UEs around it without performing a relay discovery operation. Further, after the edge UE can know the available candidate relay UEs according to the second message, it needs to actually measure the actual path quality of the direct communication path with each candidate relay UE, so as to select the most suitable candidate relay. The UE (ie the preferred relay UE) establishes the PC5 link.

In a specific implementation, one or more candidate relay UEs included in the second message may belong to the current base station or a neighboring base station.

In a specific implementation, the identifiers of one or more candidate relay UEs included in the second message may be IDs of each candidate relay UE. The ID is unique and is used to uniquely identify the UE. For example, the ID may be a cell radio network temporary identifier (cell-Radio Network Temporary Identifier, referred to as C-RNTI), a globally unique temporary UE identifier (Globally Unique Temporary UE Identify, referred to as GUTI).

In a specific implementation, the second message may further include a link quality threshold for relay selection.

For example, the second message may include an RSRP threshold configured by the base station for the edge UE and used for selecting a preferred relay UE from multiple candidate relay UEs. Correspondingly, the edge UE determines the candidate relay UE whose RSRP value is higher than the RSRP threshold in the RSRP of the direct communication link with one or more candidate relay UEs as the preferred relay UE.

In a specific implementation, the step of selecting a preferred relay UE from the one or more candidate relay UEs in step S103 may include the step of: broadcasting a direct communication request, wherein the direct communication request includes the one or more relay UEs The identifiers of the candidate relay UEs; the preferred relay UE is determined according to the responses of the one or more candidate relay UEs.

Specifically, the direct communication request may be used to request the receiver (ie, the relay UE) to establish direct communication with the sender (ie, the edge UE). In this embodiment, the direct communication request broadcast by the edge UE carries the identifiers of one or more candidate relay UEs indicated by the base station through the second message, and only the candidate relay UEs with the same identifiers may respond to the direct communication request . That is, for a relay UE whose identity does not appear in a broadcast direct communication request, even if the relay UE is located near an edge UE, the relay UE that receives the direct communication request will not respond.

Further, the direct communication request is received and the broadcasted candidate relay UE is identified to measure the RSRP of the direct communication link with the edge UE. And reply to the direct communication request when it is confirmed that the RSRP is good.

In a specific implementation, the direct communication request may include a quality of service (Quality of Service, QoS for short) indicator for establishing a direct communication path. Correspondingly, the candidate relay UE that has received the direct communication request and has a matching identifier can measure whether it meets the conditions according to the QoS indicator indicated in the direct communication request, the current service load of the candidate relay UE itself, etc., and then determine whether to respond. .

In a variant, the step S103 selecting a preferred relay UE from the one or more candidate relay UEs may include the steps of: unicasting a direct communication request to the one or more candidate UEs respectively; The preferred relay UE is determined from the responses of the one or more candidate relay UEs.

For example, when the first message includes only one candidate relay UE, the edge UE may directly unicast the direct communication request to the candidate relay UE.

For another example, when the first message includes multiple candidate relay UEs, the edge UE may also unicast a live broadcast communication request to each candidate relay UE respectively.

In a specific implementation, the responding candidate relay UE may send a direct security mode control message to the edge UE.

In a specific implementation, the determining the preferred relay UE according to the responses of the one or more candidate relay UEs may include the step of: when only a response message of a single candidate relay UE is received, measure the difference between the response and the response. link quality between the candidate relay UEs, and the responding candidate relay UE is determined as the preferred relay UE according to the measurement result.

For example, the actual measured RSRP and the RSRP threshold configured by the base station can be compared with the responding candidate relay UE. If the actually measured RSRP is greater than or equal to the RSRP threshold, the responding candidate relay UE is determined as the preferred medium. following the UE.

In a specific implementation, the determining the preferred relay UE according to the responses of the one or more candidate relay UEs may include the step of: when receiving response messages from multiple candidate relay UEs, The link quality between each candidate relay UE determines the preferred relay UE.

For example, the RSRPs actually measured between the responding candidate relay UEs can be sorted, the RSRP that is larger than the RSRP threshold configured by the base station and has the largest value can be selected, and the candidate relay UE corresponding to the selected RSRP can be selected as the preferred RSRP. Relay UE.

In a specific implementation, after determining the preferred relay UE, the edge UE may reply a direct security mode complete message to the preferred relay UE.

Further, the candidate relay UE that receives the direct security mode complete message may send a direct communication accept message to the edge UE to instruct the edge UE to accept its direct communication request.

Further, the base station releases the Uu path between the base station and the edge UE, thereby completing the conversion from the Uu path to the PC5 path.

From the above, for the edge UE side, this embodiment provides a more efficient conversion method from the Uu path to the direct communication path, which can greatly reduce the path conversion delay. Specifically, the first message sent by the edge UE does not carry the link quality measurement result with the surrounding candidate relay UEs, but reports its own position. Correspondingly, the second message sent by the base station directly indicates available candidate relay UEs around the edge UE for selection by the edge UE. Since the edge UE does not need to perform the relay discovery process, it can save the time delay of the three steps of measurement, measurement reporting and base station decision. Further, signaling overhead during path switching can be greatly reduced.

That is to say, the edge UE adopting the solution of this embodiment does not need to perform the relay discovery process, thereby saving signaling overhead.

Further, the base station selects a candidate relay UE for it according to the position of the edge UE during the path switching decision, and the edge UE can directly initiate a direct communication request without measuring the RSRP with all surrounding relay UEs. Therefore, the edge UE does not perform path switching based on the measurement, which reduces the delay of the path switching.

Further, the edge UE can only measure the RSRP with the candidate relay UE that responds to its direct communication request, which is beneficial to reduce the power consumption of the edge UE.

FIG. 2 is a schematic structural diagram of an apparatus for switching from a Uu path to a direct communication path according to an embodiment of the present invention. Those skilled in the art understand that the switching device 2 from the Uu path to the direct communication path in this embodiment can be used to implement the method and technical solution described in the embodiment shown in FIG. 1 above.

Specifically, referring to FIG. 2 , the apparatus 2 for switching the Uu path to the direct communication path in this embodiment may include: a sending module 21, configured to send a first message, wherein the first message includes location information of the edge UE; A receiving module 22, configured to receive a second message, wherein the second message includes identifiers of one or more candidate relay UEs, and the one or more candidate relay UEs are determined according to the location information of the edge UEs The handover module 23 is configured to select a preferred relay UE from the one or more candidate relay UEs, and establish a direct communication path with the preferred relay UE.

For more details on the working principle and working mode of the switching device 2 from the Uu path to the direct communication path, reference may be made to the relevant description in FIG. 1 above, which will not be repeated here.

In a specific implementation, the above-mentioned switching device 2 from the Uu path to the direct communication path may correspond to a chip with a path switching function in the user equipment, or a chip with a data processing function, such as a system-on-chip (System-On-a- Chip, abbreviated as SOC), baseband chip, etc.; or corresponding to a chip module including a chip with a path switching function in the user equipment; or corresponding to a chip module with a data processing function chip, or corresponding to the user equipment.

FIG. 3 is a flowchart of a method for indicating a candidate relay UE according to an embodiment of the present invention.

This embodiment may be performed by the base station side, for example, by the base station on the base station side. By implementing the solution of the embodiment shown in FIG. 3 , the base station can directly indicate the available candidate relay UEs to the edge UE requesting the path switching, so as to reduce the delay of the path switching.

In a specific implementation, the method for indicating a candidate relay UE provided by the following steps S301 to S303 may be executed by a chip with an indication function in the network device, or may be executed by a baseband chip in the network device. For example, network equipment may include base stations.

Specifically, referring to FIG. 3 , the method for indicating a candidate relay UE described in this embodiment may include the following steps:

Step S301, receiving a first message, wherein the first message includes location information of edge UEs;

Step S302, selecting one or more candidate relay UEs from a preset list of available relay UEs according to the location information of the edge UE;

Step S303: Generate and send a second message based on the one or more candidate relay UEs.

Those skilled in the art understand that the steps S301 to S403 can be regarded as execution steps corresponding to the steps S101 to S102 in the above-mentioned embodiment shown in FIG. 1 , and the two are complementary in specific implementation principles and logic. . Therefore, for the explanation of the terms involved in this embodiment, reference may be made to the related description of the embodiment shown in FIG. 1 , which will not be repeated here.

In a specific implementation, the base station may maintain a list of available relay UEs under the base station and neighboring base stations in real time, that is, the preset list of available relay UEs.

Specifically, the maintenance operation may include: deleting a relay UE that is no longer qualified to be a relay from the preset list of available relay UEs; adding a new relay UE to the preset list of available relay UEs; saving Location information of each relay UE.

The relay UE changes dynamically. When the link quality between the relay UE and the base station becomes poor due to mobility or other reasons, the relay UE is no longer a relay UE. At this time, the base station may remove the relay UE from the preset list of available relay UEs.

Conversely, although other UEs were not relay UEs before, but also because of mobility and link quality between base stations, the UE can become a relay UE at this time. At this time, the base station may add the UE to a preset list of available relay UEs.

For example, the method for indicating a candidate relay UE in this embodiment may further include the steps of: receiving capability reporting information; determining, according to the capability reporting information, whether to add the UE sending the capability reporting information to the preset available relay UEs list, or whether to delete the UE that sends the capability reporting information from the preset list of available relay UEs.

The capability reporting information may include: location information of the relay UE, load information, and capability of having relay services.

In response to receiving the capability report information, the base station can know which UEs under the base station are relay UEs, and can act as relays to provide relay services for edge UEs.

Further, the base station may obtain relay UE information of the adjacent base station from the adjacent base station through the Xn interface, and maintain a preset list of available relay UEs in the base station. Wherein, the Xn interface is the interface between the ng-eNB and the eNB/gNB between the independent networking wireless nodes.

In a specific implementation, when receiving the first message, the base station may traverse the preset list of available relay UEs according to the location information in the first message, so as to select the intermediate UEs located near the edge UEs and within the optimal communication range The succeeding UE sends the second message to the edge UE.

For example, the step S302 may include the step of: determining, in the preset list of available relay UEs, the relay UEs located within a predetermined radius with the position of the edge UE as the center as the one or more relay UEs Candidate relay UE.

Specifically, the direct communication between the UE and the UE can be carried out well within a certain range, and this range is the optimal communication range, that is, the above-mentioned position of the edge UE is the center of the circle and within the preset radius range. However, there are many influencing factors affecting the link quality of the direct communication path between two UEs, such as the distance between the two UEs and whether there is an obstacle between the two UEs.

Because there are many influencing factors, the base station preferably performs the first re-screening according to the distance (ie, the preset radius) when performing step S102 to generate the second message. Then the final selection is made between the UE and the UE according to the actually measured RSRP.

In a specific implementation, the preset radius is associated with at least the location information of the edge UE, the transmit power of the relay UE and/or the transmit power of the edge UE.

For example, the current positions of the edge UEs are different, and the preset radii may be different.

For another example, the specific value of the preset radius may be adjusted according to communication capabilities such as the transmit power of the edge UE and/or the relay UE.

From the above, for the base station side, this embodiment provides a more efficient method for indicating a candidate relay UE, which can greatly reduce the signaling overhead during path switching. Specifically, the base station maintains a preset list of available relay UEs, and after receiving the first message, selects a suitable candidate relay UE from the list and indicates it to the edge UE. For the base station, there is no need to receive the link quality with each candidate relay UE measured by the edge UE, which makes it possible to reduce signaling overhead. Further, the base station does not need to make a decision based on the link quality measurement result, which makes it possible to reduce the delay.

That is to say, the base station maintains a preset list of available relay UEs of its own base station and neighboring base stations, and can provide auxiliary information for the edge UE when the edge UE needs the relay UE to relay services.

FIG. 4 is a schematic structural diagram of an apparatus for indicating a candidate relay UE according to an embodiment of the present invention. Those skilled in the art understand that the device 4 for indicating the candidate relay UE in this embodiment can be used to implement the method and technical solution described in the embodiment shown in FIG. 3 above.

Specifically, referring to FIG. 4 , the device 4 for indicating a candidate relay UE in this embodiment may include: a receiving module 41 , configured to receive a first message, where the first message includes location information of the edge UE; a selection module 42 , used for selecting one or more candidate relay UEs from the preset list of available relay UEs according to the location information of the edge UE; the instruction module 43 is used for generating a second relay UE based on the one or more candidate relay UEs message and send.

For more information on the working principle and working mode of the candidate relay UE indicating device 4, reference may be made to the relevant description in FIG. 3 above, which will not be repeated here.

In a specific implementation, the above-mentioned candidate relay UE indicating device 4 may correspond to a chip with an indicating function in a network device, or a chip with a data processing function, such as a system-on-a-chip (System-On-a-Chip, SOC for short) ), baseband chip, etc.; or corresponding to a network device including a chip module with an indication function chip; or corresponding to a chip module with a data processing function chip, or corresponding to a network device.

In specific implementation, regarding each module/unit included in each device and product described in the above embodiments, it may be a software module/unit, a hardware module/unit, or a part of a software module/unit, a part of which is a software module/unit. is a hardware module/unit.

For example, for each device or product applied to or integrated in a chip, each module/unit included therein may be implemented by hardware such as circuits, or at least some of the modules/units may be implemented by a software program. Running on the processor integrated inside the chip, the remaining (if any) part of the modules/units can be implemented by hardware such as circuits; for each device and product applied to or integrated in the chip module, the modules/units contained therein can be They are all implemented by hardware such as circuits, and different modules/units can be located in the same component of the chip module (such as chips, circuit modules, etc.) or in different components, or at least some of the modules/units can be implemented by software programs. The software program runs on the processor integrated inside the chip module, and the remaining (if any) part of the modules/units can be implemented by hardware such as circuits; for each device and product applied to or integrated in the terminal, each module contained in it The units/units may all be implemented in hardware such as circuits, and different modules/units may be located in the same component (eg, chip, circuit module, etc.) or in different components in the terminal, or at least some of the modules/units may be implemented in the form of software programs Realization, the software program runs on the processor integrated inside the terminal, and the remaining (if any) part of the modules/units can be implemented in hardware such as circuits.

Further, an embodiment of the present invention further discloses a storage medium, on which a computer program is stored, and when the computer program is run by a processor, the method and technical solution described in the embodiment shown in FIG. 1 or FIG. 3 is executed. Preferably, the storage medium may include a computer-readable storage medium such as a non-volatile memory or a non-transitory memory. The storage medium may include ROM, RAM, magnetic or optical disks, and the like.

Further, an embodiment of the present invention also discloses a terminal, including a memory and a processor, the memory stores a computer program that can run on the processor, and the processor executes the above diagram when running the computer program. The method and technical scheme described in the embodiment shown in 1. Specifically, the terminal may be a UE.

Alternatively, an embodiment of the present invention further discloses a terminal, including the switching device 2 from the Uu path to the direct communication path shown in FIG. 2 . Specifically, the terminal may be a UE.

Further, an embodiment of the present invention further discloses a base station, including a memory and a processor, the memory stores a computer program that can run on the processor, and the processor executes the above diagram when running the computer program. 3. The technical solutions of the method described in the embodiment shown in 3. Specifically, the base station may be an NR base station.

Alternatively, an embodiment of the present invention further discloses a base station, including the above-mentioned candidate relay UE indication device 4 shown in FIG. 4 . Specifically, the base station may be an NR base station.

The technical solution of the present invention can be applied to a 5G (5 generation) communication system, and can also be applied to various communication systems that evolve later, such as 6G, 7G, and the like.

The technical solution of the present invention is also applicable to different network architectures, including but not limited to a relay network architecture, a dual-link architecture, and a Vehicle-to-Everything (vehicle-to-anything communication) architecture.

A base station (base station, BS) in the embodiments of the present application, which may also be referred to as base station equipment, is a device deployed in a wireless access network to provide a wireless communication function. For example, the devices that provide base station functions in 2G networks include base transceiver stations (English: base transceiver station, referred to as BTS) and base station controllers (base station controllers, BSC), and the devices that provide base station functions in 3G networks include Node B (NodeB). ) and radio network controller (RNC), the equipment that provides base station functions in 4G networks includes evolved NodeB (evolved NodeB, eNB), in wireless local area networks (wireless local area networks, WLAN), provides The equipment with base station function is an access point (AP), and the equipment providing base station function in 5G New Radio (NR) includes the node B (gNB) that continues to evolve, and provides base station in the new communication system in the future. functional equipment, etc.

The terminal in the embodiments of this application may refer to various forms of user equipment (user equipment, UE), access terminal, subscriber unit, subscriber station, mobile station, mobile station (mobile station, MS), remote station, remote terminal, Mobile equipment, user terminal, terminal equipment, wireless communication equipment, user agent or user equipment. The terminal device may also be a cellular phone, a cordless phone, a Session Initiation Protocol (SIP) phone, a Wireless Local Loop (WLL) station, a Personal Digital Assistant (PDA), a wireless communication Functional handheld devices, computing devices or other processing devices connected to wireless modems, in-vehicle devices, wearable devices, terminal devices in future 5G networks or future evolved Public Land Mobile Networks (PLMN) A terminal device, etc., is not limited in this embodiment of the present application.

This embodiment of the present application defines a terminal-to-terminal communication interface as PC5.

It should be understood that the term "and/or" in this document is only an association relationship to describe associated objects, indicating that there can be three kinds of relationships, for example, A and/or B, which can mean that A exists alone, and A and B exist at the same time , there are three cases of B alone. In addition, the character "/" in this text indicates that the related objects before and after are an "or" relationship.

The "plurality" in the embodiments of the present application refers to two or more.

The descriptions of the first, second, etc. appearing in the embodiments of the present application are only used for illustration and distinguishing the description objects, and have no order. any limitations of the examples.

The "connection" in the embodiments of the present application refers to various connection modes such as direct connection or indirect connection, so as to realize communication between devices, which is not limited in the embodiments of the present application.

The "network" and "system" that appear in the embodiments of the present application express the same concept, and the communication system is the communication network.

Although the present invention is disclosed above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention should be based on the scope defined by the claims.

Claims

A method for switching from a Uu path to a direct communication path, comprising:

sending a first message, wherein the first message includes location information of the edge UE;

receiving a second message, wherein the second message includes identifiers of one or more candidate relay UEs, and the one or more candidate relay UEs are determined according to the location information of the edge UE;

A preferred relay UE is selected from the one or more candidate relay UEs, and a direct communication path is established with the preferred relay UE.
The handover method according to claim 1, wherein the second message further includes a link quality threshold for relay selection.
The handover method according to claim 1, wherein the operation of sending the first message is performed in response to the link quality of the Uu path being lower than a first preset threshold.
The handover method according to claim 1, wherein the first message further includes the link quality of the Uu path.
The handover method according to claim 1, wherein the selecting a preferred relay UE from the one or more candidate relay UEs comprises:

broadcasting a direct communication request, wherein the direct communication request includes the identity of the one or more candidate relay UEs;

The preferred relay UE is determined based on the responses of the one or more candidate relay UEs.
The handover method according to claim 1, wherein the selecting a preferred relay UE from the one or more candidate relay UEs comprises:

unicast direct communication requests to the one or more candidate UEs, respectively;

The preferred relay UE is determined based on the responses of the one or more candidate relay UEs.
The handover method according to claim 5 or 6, wherein the determining the preferred relay UE according to the responses of the one or more candidate relay UEs comprises:

When only the response message of a single candidate relay UE is received, measure the link quality with the responding candidate relay UE, and determine the responding candidate relay UE as the Preferred relay UE;

When the response messages of multiple candidate relay UEs are received, the preferred relay UE is determined according to the link quality with the responding candidate relay UEs.
The handover method according to claim 5 or 6, wherein the direct communication request includes a service quality indicator for establishing a direct communication path.
A method for indicating a candidate relay UE, comprising:

receiving a first message, wherein the first message includes location information of the edge UE;

selecting one or more candidate relay UEs from a preset list of available relay UEs according to the location information of the edge UE;

A second message is generated and transmitted based on the one or more candidate relay UEs.
The method for indicating a candidate relay UE according to claim 9, wherein the second message further includes a link quality threshold for relay selection.
The method for indicating a candidate relay UE according to claim 9, wherein the first message is sent when it is determined that the link quality of the Uu path is lower than a first preset threshold, wherein the Uu path is Communication link between edge UE and base station.
The method for indicating a candidate relay UE according to claim 11, wherein the first message further includes the link quality of the Uu path.
The method for indicating a candidate relay UE according to claim 9, further comprising:

Receiving capability reporting information;

It is determined according to the capability reporting information whether to add the UE sending the capability reporting information to the preset available relay UE list, or whether to add the UE sending the capability reporting information from the preset available relay UEs delete from the list.
The method for indicating a candidate relay UE according to claim 9, wherein the preset list of available relay UEs includes location information of each candidate relay UE.
The method for indicating a candidate relay UE according to claim 9, wherein the preset list of available relay UEs includes relay UEs of neighboring base stations.
The method for indicating a candidate relay UE according to claim 9, wherein the preset list of available relay UEs is updated in real time.
The method for indicating a candidate relay UE according to claim 9, wherein the selecting one or more candidate relay UEs from a preset list of available relay UEs according to the location information of the edge UE comprises:

In the preset list of available relay UEs, a relay UE located within a preset radius with the position of the edge UE as the center is determined as the one or more candidate relay UEs.
The method for indicating a candidate relay UE according to claim 17, wherein the preset radius is at least related to the location information of the edge UE, the transmission power of the relay UE and/or the transmission of the edge UE. power is associated.
A switching device from a Uu path to a direct communication path, comprising:

a sending module, configured to send a first message, wherein the first message includes location information of the edge UE;

a receiving module, configured to receive a second message, wherein the second message includes the identifiers of one or more candidate relay UEs, and the one or more candidate relay UEs are determined according to the location information of the edge UEs ;

A handover module, configured to select a preferred relay UE from the one or more candidate relay UEs, and establish a direct communication path with the preferred relay UE.
A candidate relay UE indication device, comprising:

a receiving module, configured to receive a first message, wherein the first message includes location information of the edge UE;

a selection module, configured to select one or more candidate relay UEs from a preset list of available relay UEs according to the location information of the edge UE;

an instruction module, configured to generate and send a second message based on the one or more candidate relay UEs.
A storage medium on which a computer program is stored, characterized in that, when the computer program is run by a processor, the steps of the method according to any one of claims 1 to 18 are executed.
A terminal, comprising the device for switching the Uu path to the direct communication path according to claim 19, or, comprising a memory and a processor, the memory storing a computer program that can run on the processor, wherein That is, the processor executes the steps of the method according to any one of claims 1 to 8 when the processor runs the computer program.
A base station, comprising the device for indicating a candidate relay UE according to claim 20, or comprising a memory and a processor, wherein the memory stores a computer program that can run on the processor, wherein the The processor executes the steps of the method of any one of claims 9 to 18 when the processor runs the computer program.