CN114390634A

CN114390634A - Relay terminal selection method, terminal and storage medium

Info

Publication number: CN114390634A
Application number: CN202011112958.1A
Authority: CN
Inventors: 张惠英
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2020-10-16
Filing date: 2020-10-16
Publication date: 2022-04-22
Also published as: WO2022078071A1

Abstract

The embodiment of the application provides a method for selecting a relay terminal, a terminal and a storage medium, which are applied to a first UE which communicates with a second UE, and the method comprises the following steps: when the selection or reselection of the relay UE is determined, the first UE measures to obtain a first relay candidate result and receives a second relay candidate result sent by the second UE, the first relay candidate result comprises a first relay candidate list meeting the relay condition and a first channel measurement result list corresponding to the first relay candidate list, and the second relay candidate result is obtained by the second UE and comprises a second relay candidate list meeting the relay condition and a second channel measurement result list corresponding to the second relay candidate list; and selecting the target relay UE from the first relay candidate list and the second relay candidate list according to the first channel measurement result list and the second channel measurement result list. The embodiment of the application improves the relay selection efficiency.

Description

Relay terminal selection method, terminal and storage medium

Technical Field

The present application relates to the field of communications technologies, and in particular, to a method for selecting a relay terminal, a terminal, and a storage medium.

Background

For some scenarios, direct communication cannot be performed due to a certain distance between Side Link (SL) terminals (UEs), but both of the UEs are adjacent to a third party UE, and to implement inter-UE communication in this case, the third party UE may be responsible for data Relay as a Relay (Relay), which is called UE-to-UE Relay. Furthermore, for a off-line UE, if it is allowed to communicate with the Network, a neighboring on-line UE, called UE-to-Network Relay, may be selected for the off-line UE to have data therein. Both the remote UE and the Relay UE can be mobile, whether for UE-to-UE Relay or UE-to-Network Relay, and therefore the selection and reselection issues of the Relay UE must be considered.

Disclosure of Invention

The embodiment of the application provides a relay terminal selection method, a terminal and a storage medium, so as to solve the problem of low efficiency in relay selection in the prior art.

In a first aspect, an embodiment of the present application provides a method for selecting a relay terminal, where the method is applied to a first UE communicating with a second UE, and the method includes:

when the selection or reselection of the relay UE is determined, a first UE measures to obtain a first relay candidate result and receives a second relay candidate result sent by a second UE, wherein the first relay candidate result comprises a first relay candidate list meeting a relay condition and a first channel measurement result list corresponding to the first relay candidate list, and the second relay candidate result is measured by the second UE and comprises a second relay candidate list meeting the relay condition and a second channel measurement result list corresponding to the second relay candidate list;

and selecting and obtaining target relay UE from the first relay candidate list and the second relay candidate list according to the first channel measurement result list and the second channel measurement result list.

In a second aspect, an embodiment of the present application provides a terminal, which is a first terminal UE and communicates with a second UE, and includes:

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

In a third aspect, an embodiment of the present application provides a selection apparatus for a relay terminal, which is applied to a first UE communicating with a second UE, and includes:

a receiving module, configured to, when it is determined to perform selection or reselection of a relay UE, measure by a first UE to obtain a first relay candidate result and receive a second relay candidate result sent by a second UE, where the first relay candidate result includes a first relay candidate list satisfying a relay condition and a first channel measurement result list corresponding to the first relay candidate list, and the second relay candidate result is obtained by the second UE and includes a second relay candidate list satisfying the relay condition and a second channel measurement result list corresponding to the second relay candidate list;

and the determining module is used for selecting and obtaining the target relay UE from the first relay candidate list and the second relay candidate list according to the first channel measurement result list and the second channel measurement result list.

In a fourth aspect, embodiments of the present application provide a processor-readable storage medium, which stores a computer program for causing a processor to execute the method of the first aspect.

According to the method for selecting the relay terminal, the terminal and the storage medium provided by the embodiment of the application, the first UE obtains the first relay candidate result through measurement and receives the second relay candidate result sent by the second UE, so that the first UE can determine the channel quality between the first UE and the candidate relay selected by the first UE, and can determine the candidate relay selected by the second UE and the channel quality between the second UE and the candidate relay selected by the second UE, and conditions are provided for the subsequent selection of the target relay terminal; in addition, the first UE directly receives the second relay candidate result sent by the second UE, so that additional connections do not need to be established between the first UE and the candidate UE and between the candidate UE and the second UE, a process that a PC5 link needs to be established between the first UE and a plurality of candidate UEs when a relay is selected in the prior art is avoided, the number of PC5 interfaces is reduced, the feedback time of the second relay candidate result is reduced, and the efficiency of relay selection or reselection is improved.

Drawings

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

Fig. 1 is a flowchart illustrating a procedure of a method for selecting a relay terminal to which a first UE is applied in an embodiment of the present application;

fig. 2 is an interaction diagram when a target relay UE is determined in the first embodiment of the present application;

fig. 3 is an interaction diagram when determining a target relay UE in a second embodiment of the present application;

fig. 4 is a schematic structural diagram of a UE in the embodiment of the present application;

fig. 5 is a block diagram of a selection apparatus of a relay terminal applied to a first UE in the embodiment of the present application.

Detailed Description

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

In the LTE system, communication is performed in a manner of network centralized control, that is, uplink and downlink data of the UE are transmitted and received under the control of the network. The communication between the UE and the UE is forwarded and controlled by the Network, and no direct communication link exists between the UE and the UE, in this way, data transmission between the UE and the Network may be referred to as Device to Network (D2N) transmission.

The Device-to-Device (D2D) is a method in which neighboring terminals can perform data transmission via a direct link in a short distance without forwarding via a central node (i.e., a base station) or performing information transmission between UEs via a conventional cellular link. The device-to-device communication link is defined as the D2D link. In 3GPP, D2D proximity services include two major classes, D2D discovery and D2D communication. D2D discovery means that the UE uses Evolved-UMTS Terrestrial Radio Access (E-UTRA) to confirm that another UE is in its vicinity; for example, the D2D UE may use the service to find nearby taxis or to find friends in its vicinity, etc. D2D communication means that UEs close to each other directly establish a link between two UEs, so that the communication link originally transmitted through the network is converted into a local direct communication link, thereby saving a large amount of bandwidth and network efficiency; or two UEs close to each other, can obtain stable, high-speed and low-cost communication services by using direct link communication. Proximity service communication is typically performed under control or assistance of the network side, and the eNB may even dynamically allocate resources for the UEs performing the proximity service communication.

In addition, on the basis of D2D discovery and communication technology, the UE may perform data transmission with the network or other UEs by means of Relay. The Relay in the D2D system is divided into a UE-to-Network Relay and a UE-to-UE Relay. For example, in order to communicate with the Network, the UE2 outside the Network coverage uses the UE1 as a Relay node, and forwards its uplink and downlink signals through the UE1, the communication between the UE1 and the UE2 is realized by D2D communication, and the communication between the UE1 and the Network is realized by cellular communication; the way that the UE discovers/communicates with the target UE through the Relay UE is called UE-to-UE Relay, for example, the UE2 can forward its information through the UE1 in order to communicate with the UE4 that is not in its direct communication range, wherein data transmission is realized between the UE1 and the UE2, between the UE1 and the UE4 through D2D communication.

In the above two Relay scenarios, a source UE first needs to find a Relay UE capable of performing data Relay for itself, and the UE needs to be capable of performing data transmission with the source UE and a target node at the same time. The process of discovering Relay UE by source UE may be implemented by D2D discovery, and specifically there may be two ways:

the first mode is as follows: the Relay UE broadcasts a discovery signal of the Relay UE, wherein the discovery signal carries information of the Relay node, and the source UE judges whether to select the Relay UE to forward the signal of the source UE after receiving the discovery signal.

The second mode is as follows: the source UE sends a request discovery signal, wherein the signal comprises information of the source UE and information of a target node; after receiving the request discovery signal, the surrounding UE judges whether the surrounding UE can be used as Relay UE between the UE and the target node, and if so, a response discovery signal is sent; and the source UE judges whether to select the Relay UE to forward the signal of the source UE after receiving the response discovery signal.

However, after the SL Relay is introduced, for the UE-to-UE Relay, the source UE, the target UE, and the Relay are all mobile, so the Relay selection and reselection issues need to be considered.

Existing UE-to-Network Relay selection is remote terminal (remote UE) performing Relay selection and reselection based on PC5 interface channel quality between the remote UE and the Relay UE. Currently, there is no standard scheme for UE-to-UE Relay, and the Relay selection and reselection involved in the method are mainly that source UE (source UE) performs Relay selection and reselection based on PC5 interface channel quality between the source UE and the Relay UE, or the source UE or the Relay UE performs Relay selection and reselection based on PC5 interface channel quality between the source UE and the Relay UE and PC5 interface channel quality between the target UE and the Relay UE measured by the Relay UE. The method has the obvious defects that the source UE needs to trigger a plurality of candidate relay UEs to measure the PC5 port channel quality between the source UE and the target UE and carry out measurement result interaction, the source UE needs to establish PC5 link connection with the candidate relay UEs, the number of PC5 interface connections is increased, the feedback time is long, and the efficiency is low.

Therefore, embodiments of the present application provide a method for selecting a relay terminal, a terminal, and a storage medium, so as to solve the problem of low efficiency in selecting or reselecting the relay terminal in the prior art.

The method and the device are based on the same application concept, and because the principles of solving the problems of the method and the device are similar, the implementation of the device and the method can be mutually referred, and repeated parts are not repeated.

The technical scheme provided by the embodiment of the application can be suitable for various systems, particularly 5G systems. For example, the applicable system may be a global system for mobile communication (GSM) system, a Code Division Multiple Access (CDMA) system, a Wideband Code Division Multiple Access (WCDMA) General Packet Radio Service (GPRS) system, a long term evolution (long term evolution, LTE) system, an LTE Frequency Division Duplex (FDD) system, an LTE Time Division Duplex (TDD) system, an LTE-a (long term evolution) system, a universal mobile system (universal mobile telecommunications system, UMTS), a Worldwide Interoperability for Mobile Access (WiMAX) system, a New Radio network (NR 5) system, etc. These various systems include terminal devices and network devices. The System may further include a core network portion, such as an Evolved Packet System (EPS), a 5G System (5GS), and the like.

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

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

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

The present application is explained in detail below.

As shown in fig. 1, a flowchart of a method for selecting a relay terminal applied to a first UE in the embodiment of the present application is shown, where the method includes the following steps:

step 101: when the selection or reselection of the relay UE is determined, the first UE measures to obtain a first relay candidate result and receives a second relay candidate result sent by the second UE.

Specifically, the first UE may be a source UE or a target UE, and the second UE may be the source UE or the target UE; of course, when the first UE is the source UE, the second UE is the target UE; when the first UE is the target UE, the second UE is the source UE, that is, the embodiment of the present application may be applicable to both the source UE end for performing communication and the target UE end.

In addition, the first UE and the second UE communicate with each other through a Side Link (SL), or the first UE and the second UE communicate with each other through a source relay UE. Specifically, when the first UE and the second UE communicate with each other through the source Relay UE, the communication mode is referred to as UE-to-UE Relay, and the link is a D2D link.

In addition, specifically, when the first UE determines to perform selection or reselection of the relay UE, that is, when the first UE communicates with the second UE through the SL and the first UE determines to perform selection of the relay UE, or when the first UE communicates with the second UE through the source relay UE and the first UE determines to perform reselection of the relay UE, the first UE may measure itself to obtain a first relay candidate result and receive a second relay candidate result sent by the second UE, where the second relay candidate result is obtained by itself measurement of the second UE.

And the first UE receives the second relay candidate result sent by the second UE through the communication link. It should be noted that the link through which the first UE and the second UE are communicating is the original communication link before the relay reselection is not performed. Therefore, the first UE receives the second relay candidate result through the original communication link, so that the PC5 links do not need to be additionally established between the first UE and the candidate relays for measurement triggering and measurement result interaction, and the relay selection or reselection efficiency is improved.

In addition, the first relay candidate list includes a first relay candidate list satisfying the relay condition and a first channel measurement result list corresponding to the first relay candidate list. The first UE discovers and measures channels of UE which is near the first UE and can provide a Relay function, and selects a first Relay candidate list which meets Relay conditions, namely the first Relay candidate list comprises candidate relays selected by the first UE; in addition, the first channel measurement result list includes channel measurement results between the first UE and each candidate relay in the first relay candidate list. Thus, the channel quality between the first UE and the candidate relay is directly measured by the first UE, thereby making the measurement result more suitable for performing relay selection and reselection.

The second relay candidate list is obtained by measurement of the second UE and includes a second relay candidate list satisfying the relay condition and a second channel measurement result list corresponding to the second relay candidate list. The second UE discovers and measures channels of UE which is near the second UE and can provide a Relay function, and selects a second Relay candidate list which meets Relay conditions, namely the second Relay candidate list comprises candidate relays selected by the second UE; in addition, the second channel measurement result list includes channel measurement results between the second UE and each candidate relay in the second relay candidate list.

In this way, the first UE can make sure the channel quality between itself and the candidate relay selected by itself and the channel quality between the candidate relay selected by the second UE and the candidate relay selected by the second UE by obtaining the first relay candidate result of itself and receiving the second relay candidate result sent by the second UE, thereby providing conditions for the subsequent selection of the target relay terminal; in addition, the first UE directly receives the second relay candidate result sent by the second UE, so that additional connections do not need to be established between the first UE and the candidate UE and between the candidate UE and the second UE, a process that a PC5 link needs to be established between the first UE and a plurality of candidate UEs when a relay is selected in the prior art is avoided, the number of links of a PC5 interface is reduced, the feedback time of the second relay candidate result is reduced, and the efficiency of relay selection or reselection is improved.

Step 102: and selecting the target relay UE from the first relay candidate list and the second relay candidate list according to the first channel measurement result list and the second channel measurement result list.

Specifically, after the first UE obtains its own first relay candidate result and receives the second relay candidate result of the second UE, the target relay UE may be selected from the first relay candidate list and the second relay candidate list based on the first channel measurement result list in the first relay candidate result and the second channel measurement result list in the second relay candidate result, and since the channel quality between the first UE and the candidate UE and the channel quality between the second UE and the relay UE are directly measured by the first UE and the second UE, the measurement result is more suitable for relay selection and reselection, thereby ensuring the high quality of the target relay UE selected by combining the first relay candidate list and the second relay candidate list.

In this way, when determining to select or reselect the relay UE, the first UE in the present application obtains a first relay candidate result of the first UE and receives a second relay candidate result measured by the second UE, and then selects and obtains a target relay UE from the first relay candidate list and the second relay candidate list according to the first channel measurement result list and the second channel measurement result list, taking into account channel quality between the first UE and the candidate relay UE and channel quality between the second UE and the candidate relay UE, and since channel quality between the first UE and the candidate relay UE and channel quality between the second UE and the candidate relay UE are directly measured by the first UE and the second UE, the measurement results are more suitable for selecting and reselecting the relay UE; in addition, the second UE directly sends the second relay candidate result to the first UE, so that the PC5 links do not need to be additionally established between the first UE and the candidate relay UEs for measurement triggering and measurement result interaction, and the relay selection and reselection efficiency is improved.

It should be noted that, optionally, in this embodiment, the first UE further needs to send the first relay candidate result to the second UE, so as to implement interaction of the first relay candidate result.

Furthermore, optionally, in this embodiment, when determining to perform selection or reselection of the relay UE, the first UE may include any one of the following manners:

firstly, when the first UE is determined to meet the preset relay terminal selection triggering condition, the selection or reselection of the relay UE is determined.

Specifically, the first UE may determine whether relay selection is required according to a preset or configured relay terminal selection trigger condition, and determine to select or reselect the relay UE when it is determined that the preset relay terminal selection trigger condition is satisfied.

The relay terminal selection triggering condition comprises any one or combination of the following conditions:

when the first UE and the second UE communicate through SL, the channel quality or the signal receiving intensity between the first UE and the second UE is smaller than a first preset threshold value;

when the first UE and the second UE communicate through SL, the error rate or the block error rate between the first UE and the second UE is larger than a second preset threshold value;

when the first UE and the second UE communicate through the source relay UE, the channel quality or the signal receiving intensity between the first UE and the source relay UE is smaller than a third preset threshold value;

when the first UE and the second UE communicate through the source relay UE, the error rate or the block error rate between the first UE and the source relay UE is larger than a fourth preset threshold value;

when the first UE and the second UE communicate through the source relay UE, the channel quality or the signal receiving intensity between the second UE and the source relay UE is smaller than a fifth preset threshold value;

when the first UE and the second UE communicate through the source relay UE, the error rate or the block error rate between the second UE and the source relay UE is larger than a sixth preset threshold;

and receiving indication information sent by the source relay UE, wherein the indication information is used for indicating the first UE and the second UE to select or reselect the relay terminal.

That is, the first UE determines to perform selection or reselection of the relay UE when determining that the first UE itself achieves any one of the above conditions or a combination thereof.

And secondly, when the notification message sent by the second UE is received, the selection or reselection of the relay UE is determined.

The notification message is used for notifying the second UE that the preset or configured relay terminal selection trigger condition is met.

Specifically, when the first UE or the second UE meets the relay terminal selection trigger condition, the UE of the opposite terminal needs to be notified. That is, when the second UE satisfies the relay terminal selection trigger condition, a notification message is sent to the first UE to notify that the second UE has reached the relay terminal selection trigger condition and needs to perform relay selection or reselection.

Further, the notification message may be transmitted through PC5-S signaling, PC5-RRC signaling, SL MAC CE, or physical layer information, which is not particularly limited herein.

Therefore, whether the first UE meets the relay terminal triggering condition or the second UE meets the relay terminal triggering condition, the selection or reselection of the relay UE is triggered, so that the communication link can be updated when the channel quality of the link of the original communication link is poor, and the communication quality between the first UE and the second UE is ensured.

Furthermore, optionally, in this embodiment, when the first UE selects the target relay UE from the first relay candidate list and the second relay candidate list according to the first channel measurement result list and the second channel measurement result list, any one of the following manners may be included:

firstly, according to a first channel measurement result list and a second channel measurement result list, and according to a preset or configured relay selection rule, selecting and obtaining target relay UE from the first relay candidate list and the second relay candidate list.

Specifically, the relay selection rule may be a predefined rule or algorithm, for example, the relay selection rule may be that a candidate UE which exists in the first relay candidate list and the second relay candidate list at the same time and has the highest sum of two link qualities is used as a target candidate UE, where the two link qualities include a link quality between the candidate UE and the first UE and a link quality between the candidate UE and the second UE; in addition, the quality of the two sections of links can be weighted and summed, and the candidate UE with the largest weighted and summed result is selected as the target relay UE. I.e. the relay selection rules are not specifically limited herein.

In this way, the target relay UE is selected from the first relay candidate list and the second relay candidate list according to the relay selection rule by combining the first channel measurement result list and the second channel measurement result list, so that the high quality of the target relay UE is ensured, and the communication quality of a communication link after the relay is reselected is ensured.

In addition, it should be further noted that, in this embodiment, the decision UE and the non-decision UE may also be distinguished, and the decision UE may be any UE of the first UE and the second UE. At this time, if the first UE is the decision UE, the target relay UE may be selected from the first relay candidate list and the second relay candidate list only by the first UE according to a preset relay selection rule; of course, if neither the first UE nor the second UE is the decision UE, that is, there is no decision UE, it is necessary that both the first UE and the second UE select the target relay UE from the first relay candidate list and the second relay candidate list according to a preset relay selection rule.

And secondly, negotiating with the second UE to select the target relay UE from the first relay list and the second relay candidate list according to the first channel measurement result list and the second channel measurement result list.

In this manner, specifically, the first UE may negotiate with the second UE to select the target relay UE from the first relay list and the second relay candidate list.

For example, the first UE and the second UE may negotiate to determine that a candidate UE existing in the first relay candidate list and the second relay candidate list at the same time and having the highest sum of the two link qualities is a target candidate UE, or that a candidate UE having the highest weighted sum of the two link qualities is a target relay UE. The specific algorithm of negotiation is not specifically limited herein.

The target relay UE is determined through negotiation, so that the uniqueness of the selected target relay UE is ensured, and the process that the final target relay UE is determined by information interaction when the target relay UE selected by the first UE and the target relay UE selected by the second UE are inconsistent is avoided.

Thus, the selection process of the target relay UE is realized through any mode.

Optionally, after the first UE obtains the target relay UE, it is further required to send the identification information of the target relay UE to the second UE to implement interaction of information of the target relay UE, so that the second UE can specify which target relay UE the first UE selects, and thus can connect with the selected target relay UE.

In addition, after the first UE obtains the target relay UE, it may also establish a communication connection with the target relay UE and release the original communication connection.

Specifically, the first UE and the second UE may respectively establish a PC5 interface connection with the selected target relay UE, and establish an end-to-end control plane and user plane connection through the target relay UE, and communicate through the connection; in addition, the first UE and the second UE release the original communication connection, wherein the original communication connection is the communication connection before the relay UE is not selected or reselected.

It should be noted that, the first UE and the second UE may release the original communication connection based on signaling, or release the original communication connection based on a timer, or automatically release the previous communication connection after the new communication connection is established, which is not limited in this respect.

In this way, the embodiment of the present application implements selection or reselection of the target relay UE through the above process, and since the channel quality between the first UE and the candidate relay UE and the channel quality between the second UE and the candidate relay UE are considered at the same time, and the channel quality between the first UE and the candidate relay UE and the channel quality between the second UE and the candidate relay UE are directly measured by the first UE and the second UE, respectively, the measurement result is also more suitable for relay selection and reselection; in addition, the first UE and the second UE directly interact with each other, namely the link in communication is used for interacting the relay candidate results, and the PC5 link does not need to be additionally established between the first UE and the candidate relay UEs for measurement triggering and interaction of the measurement results, so that the relay selection and reselection efficiency is improved.

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

In the first embodiment, it is assumed that the first UE is a source UE, the second UE is a target UE, and the source UE and the target UE communicate directly through SL, and a Relay (Relay) needs to be selected to switch to a UE-to-UE Relay:

selection process of target relay UE as shown in fig. 2, the selection process of target relay UE includes the following steps:

step 1, the source UE and the target UE judge whether Relay selection is needed according to a Relay selection trigger condition, where the Relay selection trigger condition may be, but is not limited to, one or a combination of the following conditions:

the channel quality or the signal receiving intensity between the source UE and the target UE is smaller than a first preset threshold value;

the error rate or the block error rate between the source UE and the target UE is greater than a second preset threshold value;

receiving indication information sent by source relay UE, wherein the indication information is used for indicating the source UE and the target UE to select or reselect a relay terminal;

the relay terminal selection trigger condition may be measured or detected by any one of the two communicating parties, and the channel quality, the bit error rate or the block error rate, etc. between the source UE and the target UE may be based on a unidirectional link or a bidirectional link.

In addition, optionally, when the UE at one end meets the relay terminal selection trigger condition, a notification message may be sent to the UE at the opposite end to indicate relay selection or reselection.

And 2, the source UE and the target UE respectively measure the adjacent UEs which can provide the Relay function to discover and measure channels, and select a candidate Relay meeting the Relay condition and a list of corresponding channel quality, namely a first Relay candidate result and a second Relay candidate result are respectively obtained.

Step 3, when the source UE and the target UE distinguish the decision UE and the non-decision UE, the non-decision UE sends the relay candidate result to the decision UE; and if the decision UE does not exist, the source UE and the target UE both send the relay candidate results which are measured by the source UE and meet the relay conditions to the opposite UE.

And 4, combining the relay candidate results of the UE and the opposite end UE to perform relay selection, or negotiating by the two ends to determine which candidate relay UE is selected as the target relay UE. Of course, the decision UE may only combine the relay candidate results of the decision UE and the peer UE to perform relay selection, and if there is no decision UE, the two parties negotiate to determine which candidate relay UE is selected as the target relay UE. It should be noted that a specific selection algorithm of the target relay UE is not limited herein, and the target relay UE selected in this example is UE 1.

And step 5, the source UE and the target UE establish PC5 interface connection with the selected target relay UE (UE1) respectively.

Step 6, the source UE and the target UE establish an end-to-end control plane and user plane connection through the target relay UE (UE1), and communicate through the connection.

And 7, releasing the previous direct communication connection between the source UE and the target UE.

For some cases, the direct communication connection is not released between the source UE and the target UE through display signaling, and then the source UE and the target UE may release the direct communication connection based on a timer or automatically release the previous connection after the new connection establishment is completed.

In the second embodiment, it is assumed that the first UE is a source UE, the second UE is a target UE, the source UE and the target UE communicate with each other through a source Relay UE, and Relay reselection is performed under a UE-to-UE Relay condition:

the selection process of the target relay UE is shown in fig. 3, and the selection process of the target relay UE includes the following steps:

step 1, the source UE and the target UE judge whether Relay reselection is needed according to a Relay terminal selection triggering condition, where the Relay terminal selection triggering condition may be, but is not limited to, one or a combination of the following conditions:

the channel quality or the signal receiving intensity between the source UE and the source relay UE is smaller than a third preset threshold value;

the error rate or the block error rate between the source UE and the source relay UE is greater than a fourth preset threshold;

the channel quality or the signal receiving intensity between the target UE and the source relay UE is smaller than a fifth preset threshold value;

the error rate or the block error rate between the target UE and the source relay UE is greater than a sixth preset threshold;

And 4, combining the relay candidate results of the UE and the opposite end UE to perform relay selection, or negotiating by the two ends to determine which candidate relay UE is selected as the target relay UE. Of course, the decision UE may only combine the relay candidate results of the decision UE and the peer UE to perform relay selection, and if there is no decision UE, the two parties negotiate to determine which candidate relay UE is selected as the target relay UE. It should be noted that the specific selection algorithm of the target relay UE is not limited herein.

And step 5, the source UE and the target UE establish PC5 interface connection with the selected target relay UE respectively.

And 6, establishing end-to-end control plane and user plane connection between the source UE and the target UE through the target relay UE, and communicating through the connection.

In this way, the selection or reselection process of the relay is realized by any of the above embodiments.

Fig. 4 is a schematic structural diagram of a terminal according to an embodiment of the present application, the terminal being a first UE and communicating with a second UE, and the terminal including a memory 420, a transceiver 400, and a processor 410.

Where in fig. 4, the bus architecture may include any number of interconnected buses and bridges, with one or more processors represented by processor 410 and various circuits of memory represented by memory 420 being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 400 may be a number of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium including wireless channels, wired channels, fiber optic cables, and the like. The processor 410 is responsible for managing the bus architecture and general processing, and the memory 420 may store data used by the processor 410 in performing operations.

The processor 410 may be a Central Processing Unit (CPU), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or a Complex Programmable Logic Device (CPLD), and may also have a multi-core architecture.

A memory 420 for storing a computer program; a transceiver 400 for transceiving data under the control of the processor; a processor 410 for reading the computer program in the memory and performing the following operations:

Optionally, the determining to perform selection or reselection of the relay UE includes:

when the first UE is determined to meet the preset or configured relay terminal selection triggering condition, determining to select or reselect the relay UE; or when receiving a notification message sent by the second UE, determining to select or reselect the relay UE, where the notification message is used to notify the second UE that the preset or configured relay terminal selection trigger condition is met.

Optionally, the relay terminal selection trigger condition includes any one or a combination of the following conditions:

when the first UE and the second UE communicate through a source relay UE, the channel quality or the signal receiving intensity between the first UE and the source relay UE is smaller than a third preset threshold value;

when the first UE and the second UE communicate through a source relay UE, the error rate or the block error rate between the first UE and the source relay UE is larger than a fourth preset threshold value;

when the first UE and the second UE communicate through a source relay UE, the channel quality or the signal receiving intensity between the second UE and the source relay UE is smaller than a fifth preset threshold value;

when the first UE and the second UE communicate through a source relay UE, the error rate or the block error rate between the second UE and the source relay UE is larger than a sixth preset threshold;

Optionally, the selecting, according to the first relay candidate result and the second relay candidate result, a target relay UE from the first relay candidate list and the second relay candidate list includes:

according to the first channel measurement result list and the second channel measurement result list, selecting the target relay UE from the first relay candidate list and the second relay candidate list according to a preset or configured relay selection rule; or negotiating with the second UE to select the target relay UE from the first relay list and the second relay candidate list according to the first channel measurement result list and the second channel measurement result list.

Optionally, after the target relay UE is selected from the first relay candidate list and the second relay candidate list, the method further includes:

and sending the identification information of the target relay UE to the second UE.

and establishing communication connection with the target relay UE, and releasing the original communication connection.

Optionally, the method further comprises:

and sending the first relay candidate result to the second UE.

Optionally, the first UE is a source UE or a target UE, and the second UE is the source UE or the target UE.

It should be noted that, the above embodiments can implement the method steps of the first UE-side method embodiment and achieve the same technical effects, and detailed descriptions are omitted here.

Fig. 5 is a block diagram of a selection apparatus of a relay terminal according to an embodiment of the present application, where the apparatus is applied to a first UE communicating with a second UE, and includes:

a receiving module 501, configured to, when it is determined to perform selection or reselection of a relay UE, measure by a first UE to obtain a first relay candidate result and receive a second relay candidate result sent by a second UE, where the first relay candidate result includes a first relay candidate list satisfying a relay condition and a first channel measurement result list corresponding to the first relay candidate list, and the second relay candidate result is obtained by measurement by the second UE and includes a second relay candidate list satisfying the relay condition and a second channel measurement result list corresponding to the second relay candidate list;

a determining module 502, configured to select a target relay UE from the first relay candidate list and the second relay candidate list according to the first channel measurement result list and the second channel measurement result list.

Optionally, the determining module is specifically configured to:

Optionally, the UE further includes a first sending module, configured to send the identification information of the target relay UE to the second UE.

Optionally, the system further includes a connection releasing module, configured to establish a communication connection with the target relay UE and release the original communication connection.

Optionally, the UE further includes a second sending module, configured to send the first relay candidate result to the second UE.

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

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

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

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

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

As seen from the above embodiments, a processor-readable storage medium stores a computer program for causing a processor to execute the above relay terminal selection method.

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

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

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

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

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

Claims

1. A method for selecting a relay terminal, applied to a first UE communicating with a second UE, is characterized in that the method comprises:

2. The method of claim 1, wherein the determining to perform selection or reselection of the relay UE comprises:

when the first UE is determined to meet the preset or configured relay terminal selection triggering condition, determining to select or reselect the relay UE; alternatively, the first and second electrodes may be,

and when receiving a notification message sent by the second UE, determining to select or reselect the relay UE, wherein the notification message is used for notifying the second UE that the preset or configured relay terminal selection trigger condition is met.

3. The method according to claim 2, wherein the relay terminal selection trigger condition comprises any one or a combination of the following conditions:

4. The method of claim 1, wherein the selecting the target relay UE from the first relay candidate list and the second relay candidate list according to the first channel measurement result list and the second channel measurement result list comprises:

according to the first channel measurement result list and the second channel measurement result list, selecting the target relay UE from the first relay candidate list and the second relay candidate list according to a preset or configured relay selection rule; alternatively, the first and second electrodes may be,

and negotiating with the second UE to select the target relay UE from the first relay list and the second relay candidate list according to the first channel measurement result list and the second channel measurement result list.

5. The method of claim 1, wherein after the selecting the target relay UE from the first relay candidate list and the second relay candidate list, the method further comprises:

6. The method of claim 1, wherein after the selecting the target relay UE from the first relay candidate list and the second relay candidate list, the method further comprises:

7. The method for selecting a relay terminal according to claim 1, further comprising:

and sending the first relay candidate result to the second UE.

8. The method of any of claims 1 to 7, wherein the first UE is a source UE or a target UE, and the second UE is the source UE or the target UE.

9. A terminal, the terminal being a first UE and in communication with a second UE, comprising a memory, a transceiver, a processor:

10. The terminal of claim 9, wherein the determining to perform selection or reselection of a relay UE comprises:

11. The terminal according to claim 10, wherein the relay terminal selection trigger condition comprises any one or a combination of the following conditions:

12. The terminal of claim 9, wherein the selecting a target relay UE from the first relay candidate list and the second relay candidate list according to the first channel measurement result list and the second channel measurement result list comprises:

13. The terminal of claim 9, wherein after selecting the target relay UE from the first relay candidate list and the second relay candidate list, the method further comprises:

14. The terminal of claim 9, wherein after selecting the target relay UE from the first relay candidate list and the second relay candidate list, the method further comprises:

15. The terminal of claim 9, further comprising:

and sending the first relay candidate result to the second UE.

16. The terminal of any one of claims 9 to 15, wherein the first UE is a source UE or a target UE, and the second UE is a source UE or a target UE.

17. A relay terminal selection apparatus applied to a first UE communicating with a second UE, the apparatus comprising:

a receiving module, configured to, when it is determined to perform selection or reselection of a relay UE, measure by a first UE to obtain a first relay candidate result and receive a second relay candidate result sent by a second UE, where the first relay candidate result includes a first relay candidate list satisfying a relay condition and a first channel measurement result list corresponding to the first relay candidate list, and the second relay candidate result is obtained by measurement by the second UE and includes a second relay candidate list satisfying the relay condition and a second channel measurement result list corresponding to the second relay candidate list;

18. A processor-readable storage medium, characterized in that the processor-readable storage medium stores a computer program for causing a processor to perform the method of any one of claims 1 to 8.