CN110611943A

CN110611943A - Method and equipment for reselecting Relay UE

Info

Publication number: CN110611943A
Application number: CN201810623079.1A
Authority: CN
Inventors: 马路娟; 刘宏举; 张传欣; 刘强; 刘敏; 吕叶青
Original assignee: Hisense Group Co Ltd
Current assignee: Hisense Group Co Ltd
Priority date: 2018-06-15
Filing date: 2018-06-15
Publication date: 2019-12-24

Abstract

The invention discloses a method and equipment for reselecting Relay UE (user equipment), which are used for solving the problem that the reselection of one UE as Relay UE cannot be triggered in the prior art. In the embodiment of the present invention, the Remote UE or the base station determines, according to the reselection message, whether to reselect the Relay UE for the Remote UE, and compared with the prior art, the embodiment of the present invention provides a scheme for triggering reselection of the Relay UE, which determines whether to reselect the Relay UE for the Remote UE, according to the acquired performance information of the source Relay UE, or the performance information of the Relay UE and the first channel quality between the Remote UE and the source Relay UE, so as to improve the communication capability of the Remote UE and improve the system performance.

Description

Method and equipment for reselecting Relay UE

Technical Field

The present invention relates to the field of internet of things, and in particular, to a method and a device for reselecting Relay User Equipment (Relay terminal).

Background

The internet of things is an internet connected with objects, the basis of the internet of things is still the internet, and the internet of things is an extended and expanded network on the basis of the internet, and a user side of the internet of things can be extended and expanded to any object to carry out information exchange and communication between the objects.

Among the various terminals of the internet of things, there are some terminals (Remote UEs)) that cannot directly communicate with the base station. In order to realize data transmission of the Remote UE, the Remote UE may connect to the base station via the Relay UE by establishing a D2D communication link with another Relay UE, thereby completing data transmission.

Generally, if there are multiple UEs that can be selected, a Remote UE first needs to select one UE as a Relay UE, establish a connection with the UE, and implement data transmission with a base station through the UE. However, the selected Relay UE may not always provide service to the Remote UE. When Relay UE connected to the Relay UE cannot provide service for the Relay UE, it is necessary to reselect one UE as the Relay UE.

But there is currently no clear solution on how to trigger the reselection of a UE as a Relay UE.

In summary, in the prior art, it is not possible to trigger the reselection of one UE as a Relay UE.

Disclosure of Invention

The invention provides a method and equipment for reselecting Relay UE (user equipment), which are used for solving the problem that the reselection of one UE as the Relay UE cannot be triggered in the prior art.

In a first aspect, an embodiment of the present invention provides a method for reselecting a Relay UE, where the method includes:

when a Remote UE is connected with a base station through a source Relay UE, determining reselection information, wherein the reselection information is performance information of the source Relay UE or the reselection information comprises the performance information of the source Relay UE and first channel quality between the Remote UE and the source Relay UE; then, according to the reselection information, judging whether to perform reselection of Relay UE aiming at the Remote UE; wherein the capability information of the source Relay UE includes part or all of the following: the remaining energy of the source Relay UE, the load of the source Relay UE, and a second channel quality between the source Relay UE and the base station.

In the method, the Remote UE judges according to the reselection message and determines whether to reselect the Relay UE for the Remote UE. Compared with the prior art, the embodiment of the invention judges according to the performance information of the source Relay UE, or the performance information of the source Relay UE and the channel quality between the Relay UE and the source Relay UE, and determines whether to reselect the Relay UE for the Relay UE, so that the embodiment of the invention provides a scheme for triggering the reselection of one UE as the Relay UE, thereby improving the communication capacity of the Relay UE and improving the system performance.

In a possible implementation manner, the Remote UE receives the performance information sent by the source Relay UE or the base station, so that the performance information of the source Relay UE can be determined according to the received performance information, and further whether to perform the reselection of the Relay UE for the Remote UE can be determined according to the performance information of the source Relay UE in the reselection information.

When the target Relay UE is selected according to the information for selecting the target Relay UE, the Remote UE can determine the target Relay UE and then inform the base station, and the base station can also determine the target Relay UE according to the information uploaded by the Remote UE and used for selecting the target Relay UE.

In a first mode, after judging whether Relay UE is reselected for the Relay UE according to the reselection information, if it is determined that the Relay UE needs to be reselected for the Relay UE, the Relay UE determines information for selecting target Relay UE according to measurement parameters configured by a base station, selects the target Relay UE according to the information for selecting the target Relay UE, and notifies the base station of the selected target Relay UE; wherein the information for selecting the target Relay UE includes part or all of the following: the remaining energy of the candidate Relay UE, the load of the candidate Relay UE, the first channel quality between the candidate Relay UE and the Remote UE, the second channel quality between the candidate Relay UE and the base station, and the ID of the cell to which the candidate Relay UE belongs.

According to the method, after the Remote UE determines that Relay UE reselection needs to be performed on the Remote UE, information for selecting target Relay UE is determined according to measurement parameters configured by a base station, then the target Relay UE is selected according to the information for selecting the target Relay UE, and the base station is informed of the selected target Relay UE, so that the Remote UE can be connected with the target Relay UE, and therefore the Remote UE is triggered to perform the reselection of the Relay UE after the source Relay UE connected with the Remote UE cannot continuously provide Relay service for the Remote UE, the communication capability of the Remote UE can be improved, and the system performance is improved.

In a second mode, after judging whether Relay UE is reselected for the Remote UE according to the reselection information, if the Relay UE is determined to need to be reselected for the Remote UE, the Remote UE determines information for selecting target Relay UE according to measurement parameters configured by a base station, reports the information for selecting the target Relay UE to the base station, and the base station selects the target Relay UE; wherein the information for selecting the target Relay UE includes part or all of the following: the remaining energy of the candidate Relay UE, the load of the candidate Relay UE, the first channel quality between the candidate Relay UE and the Remote UE, the second channel quality between the candidate Relay UE and the base station, and the ID of the cell to which the candidate Relay UE belongs.

In the method, when the Relay UE is determined to need to be reselected aiming at the Relay UE, the Relay UE determines information for selecting the target Relay UE according to the measurement parameters configured by the base station, reports the information for selecting the target Relay UE to the base station, and then determines the target Relay UE according to the received information for selecting the target Relay UE. And then the Remote UE can establish connection with the target Relay UE, so that the Remote UE is triggered to reselect the Relay UE and establish connection with the selected target Relay UE after the source Relay UE connected with the Remote UE cannot continuously provide Relay service for the Remote UE, and data transmission is carried out through the target Relay UE, therefore, the communication capacity of the Remote UE can be improved, and the system performance is further improved.

In a second aspect, an embodiment of the present invention provides a method for reselecting a Relay UE, where the method includes:

when a base station is connected with a Remote UE through a source Relay UE, determining reselection information, wherein the reselection information is performance information of the source Relay UE or comprises the performance information of the source Relay UE and first channel quality between the Remote UE and the source Relay UE; then, according to the reselection information, judging whether to perform reselection of Relay UE aiming at the Remote UE; wherein the capability information of the source Relay UE includes part or all of the following: the remaining energy of the source Relay UE, the load of the source Relay UE, and a second channel quality between the source Relay UE and the base station.

In the method, when the base station is connected with the Remote UE through the source Relay UE, the reselection information is determined, and then the judgment is carried out according to the reselection information to determine whether to carry out the reselection of the Relay UE aiming at the Remote UE. Compared with the prior art, the embodiment of the invention judges according to the performance information of the source Relay UE, or the performance information of the source Relay UE and the first channel quality between the Relay UE and the source Relay UE, and determines whether to reselect the Relay UE for the Relay UE, so that the embodiment of the invention provides a scheme for triggering the reselection of one UE as the Relay UE, the Relay UE can establish connection with the selected target Relay UE, and data transmission is carried out through the target Relay UE, thereby improving the communication capacity of the Relay UE and improving the system performance.

In a possible implementation manner, the base station determines whether to perform reselection of Relay UE for the Remote UE according to the determined reselection information, and configures measurement parameters to the Remote UE after determining that the Relay UE needs to be reselected.

According to the method, after the fact that the Relay UE needs to be reselected aiming at the Relay UE is determined, measurement parameters are configured for the Relay UE so as to obtain necessary parameter information and facilitate the subsequent selection of the target Relay UE.

In a possible implementation manner, the base station selects a target Relay UE according to information for selecting the target Relay UE reported by the Remote UE; wherein the information for selecting the target Relay UE includes part or all of the following: the residual energy of the candidate Relay UE, the load of the candidate Relay UE, the first channel quality between the candidate Relay UE and the Remote UE, the second channel quality between the candidate Relay UE and the base station, and the ID of the cell to which the candidate Relay UE belongs.

According to the method, the base station determines the target Relay UE according to the information fed back by the Remote UE and used for selecting the target Relay UE, and the information used for selecting the target Relay UE comprises various performance parameters of the candidate Relay UE, so that the performance of the candidate Relay UE can be comprehensively considered, and the target Relay UE with the most stable performance is selected, and the system stability is improved.

In a third aspect, an embodiment of the present invention further provides a Remote UE for reselecting a Relay UE, where the Remote UE includes: at least one processor and at least one memory, the apparatus having functionality to implement the embodiments of the first aspect described above.

In a fourth aspect, an embodiment of the present invention further provides a base station for reselecting a Relay UE, where the base station includes: at least one processor and at least one memory, the apparatus having functionality to implement the embodiments of the second aspect described above.

In a fifth aspect, an embodiment of the present invention further provides a Remote UE for reselecting a Relay UE, where the Remote UE includes a determining module and a determining module, and the device has functions of implementing the embodiments of the first aspect.

In a sixth aspect, an embodiment of the present invention further provides a base station for reselecting a Relay UE, where the base station includes a determining module and a determining module, and the base station has functions of implementing the embodiments of the second aspect.

In addition, for technical effects brought by any one implementation manner of the third aspect to the sixth aspect, reference may be made to technical effects brought by different implementation manners of the first aspect, and details are not described here.

These and other aspects of the present application will be more readily apparent from the following description of the embodiments.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without inventive exercise.

Fig. 1 is a flowchart illustrating a method for reselecting a Relay UE according to an embodiment of the present invention;

FIG. 2 is a diagram illustrating a first scenario provided by an embodiment of the present invention;

fig. 3 is a timing diagram illustrating a first method for reselecting a Relay UE according to an embodiment of the present invention;

fig. 4 is a schematic diagram of a second scenario provided in the embodiment of the present invention;

fig. 5 is a timing diagram illustrating a second method for reselecting a Relay UE according to an embodiment of the present invention;

fig. 6 is a schematic diagram of a scenario three provided in the embodiment of the present invention;

fig. 7 is a timing diagram illustrating a third method for reselecting a Relay UE according to an embodiment of the present invention;

fig. 8 is a schematic diagram of a scenario four provided in the embodiment of the present invention;

fig. 9 is a timing diagram illustrating a fourth method for reselecting a Relay UE according to an embodiment of the present invention;

fig. 10 is a flowchart illustrating a second method for reselecting a Relay UE according to an embodiment of the present invention;

fig. 11 is a timing diagram illustrating a fifth method for reselecting a Relay UE according to an embodiment of the present invention;

fig. 12 is a timing diagram illustrating a sixth method for reselecting a Relay UE according to an embodiment of the present invention;

fig. 13 is a timing diagram illustrating a seventh method for reselecting a Relay UE according to an embodiment of the present invention;

fig. 14 is a timing diagram illustrating an eighth method for reselecting a Relay UE according to an embodiment of the present invention;

fig. 15 is a schematic structural diagram of a first Remote UE according to an embodiment of the present invention;

fig. 16 is a schematic structural diagram of a first base station according to an embodiment of the present invention;

fig. 17 is a schematic structural diagram of a second Remote UE according to an embodiment of the present invention;

fig. 18 is a schematic structural diagram of a second base station according to an embodiment of the present invention.

Detailed Description

The embodiment of the invention relates to a Remote UE, a Relay UE and a base station. Wherein, the Remote UE is connected with the base station through the Relay UE. When the base station has data to be transmitted to the Remote UE, the data information is transmitted to the Relay UE, and then the Relay UE transmits the data information to the Remote UE; when the Relay UE has data to be transmitted to the base station, the data information is transmitted to the Relay UE, and then the Relay UE transmits the data information to the base station.

The embodiment of the invention can judge whether the source Relay UE can be continuously used as the Relay UE according to the performance information of the source Relay UE of the Relay UE, or the performance information of the source Relay UE and the sidelink channel quality between the Relay UE and the source Relay UE, and if not, the Relay UE can be selected for the Relay UE again.

In order to make the objects, technical solutions and advantages of the present invention clearer, the present invention will be described in further detail with reference to the accompanying drawings, and it is apparent that the described embodiments are only a part of the embodiments of the present invention, 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 invention.

As shown in fig. 1, an embodiment of the present invention provides a method for reselecting a Relay UE, where the method includes:

step 100, when a Remote UE is connected to a base station through a source Relay UE, determining reselection information, where the reselection information is performance information of the source Relay UE or the reselection information includes the performance information of the source Relay UE and a first channel quality between the Remote UE and the source Relay UE;

and step 101, the Remote UE judges whether to reselect the Relay UE aiming at the Remote UE according to the reselection information.

In the embodiment of the invention, the Remote UE judges according to the reselection message and determines whether to reselect the Relay UE aiming at the Remote UE. Compared with the prior art, the embodiment of the invention judges whether to reselect the Relay UE aiming at the Relay UE according to the acquired performance information of the source Relay UE or the performance information of the source Relay UE and the first channel quality between the Relay UE and the source Relay UE, so that the embodiment of the invention provides a scheme for triggering the reselection of one UE as the Relay UE, thereby improving the communication capacity of the Relay UE and perfecting the system performance.

Wherein the capability information of the source Relay UE includes part or all of the following:

the remaining energy of the source Relay UE, the load of the source Relay UE, and a second channel quality between the source Relay UE and the base station.

Wherein, the residual energy of the source Relay UE: the remaining power of Relay UE currently connected to the Remote UE is referred to, and when the remaining power of the Relay UE is too low, the Relay capability cannot be maintained due to energy exhaustion, so that data transmission of the Remote UE via the Relay UE is interrupted.

Load of source Relay UE: the number of the UEs for which Relay service is provided by Relay UE currently connected to the Remote UE is referred to, and when the load of the Relay UE is too large, the Relay capability is lost due to overload, so that the Remote UE cannot perform data transmission through the currently connected Relay UE.

First channel quality between Remote UE and source Relay UE: the UE refers to the channel quality of the sidelink between the Remote UE and the source Relay UE, and when the channel quality of the sidelink between the Remote UE and the source Relay UE does not meet the set threshold, data transmission cannot be performed between the Remote UE and the source Relay UE.

Second channel quality between source Relay UE and base station: the channel quality of the Uulink between the source Relay UE and the base station is referred, when the channel quality of the sidelink between the source Relay UE and the base station connected with the Relay UE does not meet the set threshold, data transmission cannot be carried out between the Relay UE and the base station, and then the Relay UE cannot carry out data transmission between the source Relay UE and the base station connected with the Relay UE.

In specific implementation, when data transmission between a Remote UE and a base station is implemented by the Remote UE, an RRC Sidelink needs to be established between the Remote UE and the Remote UE, and the RRC Sidelink has two types, one bidirectional type and the other unidirectional type.

For the bidirectional type, the Remote UE may receive and transmit data through the RRC sidelink of the bidirectional type; for the unidirectional type, the Remote UE may transmit data through an RRC sidelink of the unidirectional type.

The following description is made separately for different types of RRC sidelink.

Type 1, bidirectional type.

In the embodiment of the invention, the Remote UE judges whether to reselect the Remote UE according to the performance information of the source Remote UE or the performance information of the source Remote UE and the quality of a sidelink channel between the Remote UE accessed to the source Remote UE and the source Remote UE.

And in the triggering mode 1, the Remote UE judges whether to reselect the Remote UE according to the residual energy of the source Remote UE.

First, the Remote UE needs to determine the residual energy of the source Relay UE and a corresponding residual energy threshold, and then determines whether to perform reselection of the Relay UE for the Remote UE.

In specific implementation, the base station may send the residual energy threshold to the Remote UE, and then the Remote UE receives the residual energy threshold. In this way, when judging whether to reselect Relay UE for the Relay UE, the Relay UE compares the residual energy of the source Relay UE with the residual energy threshold value sent by the base station, and further determines whether to reselect the Relay UE for the Relay UE.

The base station may send the residual energy threshold to the Remote UE when the Remote UE first selects the Relay UE, and then does not send the residual energy threshold repeatedly; the remaining energy threshold may also be sent to the Remote UE each time it selects a Relay UE. In addition, the remaining energy threshold may also be preconfigured in the Remote UE.

When a Remote UE establishes a connection with a base station through a source Relay UE, the residual energy of the source Relay UE needs to be determined before determining whether to perform reselection of the Relay UE for the Remote UE according to the residual energy of the source Relay UE, so that whether to perform reselection of the Relay UE for the Remote UE can be determined.

Optionally, the Remote UE determines the residual energy of the source Relay UE by receiving the residual energy sent by the source Relay UE or the base station.

In a specific implementation, there are two main types of residual energy that a Remote UE determines to be the source Relay UE.

1. And the Remote UE receives the residual energy directly transmitted by the source Relay UE.

In the method, the Remote UE directly receives the residual energy sent by the source Relay UE, and compared with the residual energy of the source Relay UE obtained by forwarding by the base station, the Remote UE directly receives the information which can be acquired more quickly.

2. And the Remote UE receives the residual energy sent by the source Relay UE through the base station.

In the method, the residual energy of the source Relay UE may be sent to the base station by the source Relay UE first, and then sent to the Remote UE by the base station, so that the Remote UE acquires the residual energy of the source Relay UE.

After determining the residual energy of the source Relay UE, the Relay UE judges according to the residual energy of the source Relay UE and a set residual energy threshold value, and determines whether to reselect the Relay UE for the Relay UE.

In specific implementation, the Remote UE determines whether the residual energy of the source Relay UE connected to the Remote UE is greater than a set residual energy threshold, and if so, maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, when the Remote UE determines whether to reselect the Relay UE for the Remote UE, if the Remote UE determines that the residual energy is greater than the residual energy threshold, it is determined that the residual energy of the source Relay UE is sufficient and can stably provide a service for the Remote UE, and the Remote UE is connected to the source Relay UE; otherwise, determining that the residual energy of the currently connected source Relay UE is too low to provide service for the Relay UE well, so that the Relay UE is reselected for the Relay UE. Therefore, when the residual energy of Relay UE connected with the Relay UE is too low, the Relay UE can be triggered to be reselected aiming at the Relay UE, so that the Relay UE can be connected with the reselected Relay UE in time, and the interruption of data transmission between the Relay UE and the base station due to the energy exhaustion of the source Relay UE is avoided. The communication capability of Remote UE is improved, and the system performance is improved.

For example: the residual energy threshold of the source Relay UE currently connected by the Remote UE determined by the base station is 50% of electric quantity, and when the residual energy of the source Relay UE currently connected by the Remote UE is 35% of electric quantity, the Remote UE judges to reselect the Remote UE for the Remote UE because the residual energy of the source Relay UE is less than the residual energy threshold.

And 2, judging whether to reselect the Relay UE by the Remote UE according to the load of the source Relay UE by the Remote UE.

First, the Remote UE needs to determine the load threshold of the source Relay UE.

In a specific implementation, the base station may send the load threshold to the Remote UE, and then the Remote UE receives the load threshold. In this way, when determining whether to perform reselection of Relay UE for the Relay UE, the Relay UE may compare the load of the source Relay UE with the load threshold sent by the base station to determine whether to perform reselection of the Relay UE for the Relay UE.

The base station may send the load threshold to the Remote UE when the Remote UE first selects the Relay UE, and then does not send the load threshold repeatedly; the load threshold may also be sent to the Remote UE each time the Remote UE selects a Relay UE. In addition, the load threshold of the Relay UE may also be configured in advance in the Remote UE.

After determining the load threshold of the source Relay UE, the Relay UE needs to determine the current load of the source Relay UE, and can determine whether to perform reselection of the Relay UE for the Relay UE.

Optionally, the Remote UE receives the load sent by the source Relay UE or the base station.

In a specific implementation, the Remote UE determines that the load of the source Relay UE is mainly two.

1. And the Remote UE receives the load directly sent by the source Relay UE.

In the method, the Remote UE directly receives the load sent by the source Relay UE, and compared with the load of the source Relay UE obtained by forwarding through the base station, the load sent by the source Relay UE directly received can acquire the required information more quickly.

2. And the Remote UE receives the load sent by the source Relay UE through the base station.

In the method, the load of the source Relay UE may be sent to the base station by the source Relay UE first, and then sent to the Remote UE by the base station, so that the Remote UE obtains the load of the source Relay UE.

After determining the load of the source Relay UE, the Relay UE judges according to the load of the source Relay UE and a set load threshold value, and determines whether to reselect the Relay UE for the Relay UE.

In specific implementation, the Remote UE determines whether the load of the source Relay UE connected to the Remote UE is smaller than a set load threshold, and if so, maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, when the Remote UE determines whether to reselect the Relay UE for the Remote UE, if the Remote UE determines that the load of the Relay UE is smaller than a set load threshold, it is determined that the source Relay UE is not overloaded, and the Remote UE can stably provide a service for the Remote UE, and maintains the currently connected source Relay UE; otherwise, determining that the currently connected source Relay UE is overloaded and cannot maintain the Relay capability, and performing reselection of Relay UE for the Remote UE. Therefore, the Remote UE can select and access a new Relay UE when the source Relay UE is overloaded, thereby avoiding the interruption of data transmission between the Remote UE and the base station caused by the overload of the source Relay UE and further improving the system stability.

For example: the load threshold of source Relay UE connected with the Remote UE determined by the base station is 4 UEs, currently, the load of the source Relay UE determined by the Remote UE to be connected is 3 UEs, and at the moment, the Remote UE determines that the load of the source Relay UE is smaller than the set load threshold, so that the Remote UE maintains the connected source Relay UE.

And 3, the Remote UE judges whether to reselect the Remote UE according to the quality of the Ullink channel between the source Remote UE and the base station.

First, the Remote UE needs to determine the Uulink channel quality threshold between the source Relay UE and the base station.

In specific implementation, the base station may send a Uulink channel quality threshold between the Relay UE and the base station to the Remote UE, and then the Remote UE receives the load threshold sent by the base station. As such, the Remote UE may compare the Uulink channel quality between the source Relay UE and the base station with the Uulink channel quality threshold between the source Relay UE and the base station sent by the base station to determine whether to perform reselection of the Relay UE for the Remote UE.

The base station can send a Uulink channel quality threshold value between Relay UE and the base station to the Relay UE when the Relay UE selects the Relay UE for the first time, and then the transmission is not repeated; or sending a uuink channel quality threshold between the source Relay UE and the base station to the Remote UE each time the Remote UE selects the Relay UE. In addition, the uuink channel quality threshold between the source Relay UE and the base station may also be preconfigured in the Remote UE.

After determining the uuink channel quality threshold between the source Relay UE and the base station, the Remote UE needs to determine the uuink channel quality between the current source Relay UE and the base station, and can determine whether to reselect the Relay UE for the Remote UE.

Optionally, the Remote UE receives the source Relay UE or the Uulink channel quality between the source Relay UE and the base station sent by the base station.

In a specific implementation, the Remote UE determines that there are two main types of uuink channel quality between the source Relay UE and the base station.

1. And the Remote UE receives the Uulink channel quality between the source Relay UE and the base station directly sent by the source Relay UE.

In the method, the Remote UE directly receives the quality of the uuink channel between the source Relay UE and the base station sent by the source Relay UE, and compared with the quality of the uuink channel between the source Relay UE and the base station obtained by forwarding through the base station, the quality of the uuink channel between the source Relay UE and the base station sent by the source Relay UE can be directly received, so that the required information can be obtained more quickly.

2. And the Remote UE receives the Uulink channel quality between the source Relay UE and the base station, which is sent by the source Relay UE through the base station.

In the method, the uuink channel quality between the source Relay UE and the base station may be sent to the base station by the source Relay UE first, and then sent to the Remote UE by the base station, so that the Remote UE acquires the uuink channel quality between the source Relay UE and the base station.

After determining the quality of the Ulink channel between the source Relay UE and the base station, the Relay UE judges according to the quality of the Ulink channel between the source Relay UE and the base station and a set threshold value of the quality of the Ulink channel between the source Relay UE and the base station, and determines whether to reselect the Relay UE for the Relay UE.

In specific implementation, the Remote UE determines whether the quality of a Uulink channel between a source Relay UE connected to the Remote UE and a base station is greater than a set Uulink channel quality threshold, and if so, maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, when the Remote UE determines whether to reselect the Relay UE for the Remote UE, if the Remote UE determines that the quality of the uuink channel between the source Relay UE and the base station is greater than the set quality threshold of the uuink channel, it is determined that the quality of the channel between the source Relay UE and the base station is good, data transmission can be stably performed, and the Remote UE maintains the currently connected source Relay UE; otherwise, it is determined that the Uulink channel quality between the currently connected source Relay UE and the base station is poor and data transmission is not possible, that is, the source Relay UE cannot maintain Relay capability, so that the Relay UE is reselected for the Remote UE. Therefore, the Remote UE can select and access a new Relay UE when the quality of the Ulink channel between the source Relay UE and the base station is poor and the Relay capability cannot be maintained, thereby avoiding the interruption of data transmission between the Remote UE and the base station caused by the fact that the quality of the Ulink channel between the source Relay UE and the base station cannot realize data transmission.

For example: the UE determines that the quality of a Ullink channel between source Relay UE connected with the Remote UE and the base station is 25, and currently, the UE determines that the quality threshold of the Ullink channel between the source Relay UE and the base station is 20, and at this time, the Remote UE determines that the quality of the Ullink channel between the source Relay UE and the base station is less than the set quality threshold of the Ullink channel between the source Relay UE and the base station, so that the Remote UE is reselected for the Remote UE.

And 4, judging whether to reselect the Relay UE by the Remote UE according to the residual energy of the source Relay UE and the sidelink channel quality between the Remote UE and the source Relay UE by the Remote UE.

First, the Remote UE needs to determine the residual energy threshold of the source Relay UE and the sidelink channel quality threshold between the Remote UE and the source Relay UE.

In specific implementation, the Remote UE receives a residual energy threshold of the source Relay UE and a sidelink channel quality threshold between the Remote UE and the source Relay UE, which are sent by the base station. In this way, the Remote UE can obtain the residual energy threshold of the source Relay UE and the sidelink channel quality threshold between the Remote UE and the source Relay UE, and then when it is determined whether to perform reselection of the Relay UE for the Remote UE, compare the sidelink channel quality with the sidelink channel quality threshold, and compare the residual energy threshold of the source Relay UE with the residual energy threshold, so as to determine whether to perform reselection of the Relay UE for the Remote UE.

The base station may send the residual energy threshold and the sidelink channel quality threshold to the Remote UE when the Remote UE selects the Relay UE for the first time, and then does not send repeatedly; the residual energy threshold and sidelink channel quality threshold may also be sent to the Remote UE each time a Relay UE is selected. In addition, the residual energy threshold and the sidelink channel quality threshold may also be preconfigured in the Remote UE.

After determining a residual energy threshold of source Relay UE and a sidelink channel quality threshold between the Relay UE and the source Relay UE, the Relay UE judges whether to reselect the Relay UE for the Relay UE.

Optionally, the Remote UE receives the residual energy sent by the source Relay UE or the base station and the sidelink channel quality between the Remote UE and the source Relay UE.

In a specific implementation, there are two main types of residual energy of the source Relay UE and sidelink channel quality between the Relay UE and the source Relay UE determined by the Relay UE.

1. And the Remote UE receives the residual energy directly transmitted by the source Relay UE and the sidelink channel quality between the Remote UE and the source Relay UE.

In the method, the Remote UE directly receives the residual energy sent by the source Relay UE and the sidelink channel quality between the Remote UE and the source Relay UE, and compared with the residual energy of the source Relay UE and the sidelink channel quality between the Remote UE and the source Relay UE which are obtained by forwarding through the base station, the Remote UE can directly receive the required information more quickly.

2. And the Remote UE receives the residual energy sent by the source Relay UE through the base station and the sidelink channel quality between the Remote UE and the source Relay UE.

In the method, the residual energy of the source Relay UE and the quality of the sidelink channel between the Relay UE and the source Relay UE may be sent to the base station by the source Relay UE first, and then sent to the Relay UE by the base station, so that the Relay UE acquires the residual energy of the source Relay UE and the quality of the sidelink channel between the Relay UE and the source Relay UE.

In addition, Remote UE can also directly measure the sidelink channel quality with the currently connected Relay UE.

After determining the residual energy of the source Relay UE and the sidelink channel quality between the Relay UE and the source Relay UE, the Relay UE judges according to the residual energy of the source Relay UE, the sidelink channel quality between the Relay UE and the source Relay UE, and the set sidelink channel quality threshold and residual energy threshold, and determines whether to reselect the Relay UE for the Relay UE.

Optionally, the Remote UE determines whether the residual energy is greater than a residual energy threshold, and whether the sidelink channel quality is greater than a sidelink channel quality threshold, if so, maintains a currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, when the Remote UE uses the residual energy and the sidelink channel quality between the Remote UE and the source Relay UE as the basis for determining whether to reselect the Remote UE for the Remote UE, the currently connected source Relay UE is maintained only when both the residual energy of the source Relay UE connected to the Remote UE and the sidelink channel quality between the Remote UE and the source Relay UE are greater than the set threshold; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, when the residual energy of the source Relay UE is too low or the sidelink channel quality between the Relay UE and the source Relay UE is too low, a new Relay UE is selected and accessed, thereby avoiding the possibility of data transmission interruption between the Relay UE and the base station due to the source Relay UE being unable to maintain the Relay capability, improving the communication capability of the Relay UE and improving the system performance.

For example:

expressing the sidelink channel quality between the Remote UE and the currently connected source Relay UE by numerical values, wherein the larger the numerical value is, the better the sidelink channel quality between the Remote UE and the currently connected source Relay UE is, and the sidelink channel quality threshold value between the Remote UE and the currently connected source Relay UE determined by the base station is 25; in addition, the residual energy threshold of the source Relay UE to which the Remote UE is currently connected, which is determined by the base station, is 50% of the electric quantity.

If the residual energy of the source Relay UE currently connected by the Relay UE is 35% of electric quantity, and the sidelink channel quality between the Relay UE and the source Relay UE currently connected by the Relay UE is 22, the Relay UE is reselected for the Relay UE because the residual energy of the source Relay UE is less than the residual energy threshold value and the sidelink channel quality between the Relay UE and the source Relay UE is less than the sidelink channel quality threshold value.

And 5, the Remote UE judges whether to reselect the Remote UE according to the load of the source Remote UE and the sidelink channel quality between the Remote UE and the source Remote UE.

The Remote UE needs to determine a load of a source Relay UE, a sidelink channel quality between the Remote UE and the source Relay UE, a load threshold of the source Relay UE, and a sidelink channel quality threshold, and then determines whether to reselect the Relay UE for the Remote UE.

In the triggering mode 5, the Remote UE determines the load of the source Relay UE, the sidelink channel quality between the Remote UE and the source Relay UE, the load threshold of the source Relay UE, and the sidelink channel quality threshold, which are similar to the triggering modes one to four, and therefore, description is omitted.

After determining the load of source Relay UE and the sidelink channel quality between Remote UE and the source Relay UE, and determining the load threshold of the source Relay UE and the sidelink channel quality threshold between Remote UE and the source Relay UE, the Remote UE judges according to the load of the source Relay UE, the sidelink channel quality between Remote UE and the source Relay UE, and the received sidelink channel quality threshold and the load threshold, and determines whether to reselect Relay UE for Remote UE.

Optionally, the Remote UE determines whether the load of the source Relay UE is smaller than a set load threshold, and whether the sidelink channel quality is greater than a set sidelink channel quality threshold, if so, the source Relay UE currently connected is maintained; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, when the Remote UE uses the load of the source Relay UE and the sidelink channel quality between the Remote UE and the source Relay UE as the basis for determining whether to reselect the Relay UE for the Remote UE, the source Relay UE can maintain the Relay capability only when the load of the source Relay UE is smaller than the set load threshold and the sidelink channel quality is greater than the set sidelink channel quality threshold, and the Remote UE maintains the currently connected source Relay UE; otherwise, the Remote UE reselects the Relay UE for the Remote UE. This may make the communication between the Remote UE and the currently connected Relay UE more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

For example: the base station sets a sidelink channel quality threshold between Remote UE and source Relay UE to be 24; the load threshold for the source Relay UE is 4 UEs.

If the load of the source Relay UE is determined to be 3 UEs and the sidelink channel quality between the Relay UE and the source Relay UE is determined to be 26, the currently connected source Relay UE is maintained because the load of the source Relay UE is smaller than the load threshold and the sidelink channel quality between the Relay UE and the source Relay UE is larger than the sidelink channel quality threshold.

And 6, the Remote UE judges whether to reselect the Remote UE for the Remote UE according to the quality of a Uulink channel between the source Remote UE and the base station and the quality of a sidelink channel between the Remote UE and the source Remote UE.

Firstly, Remote UE needs to determine the quality of a Uulink channel between source Relay UE and a base station, the quality of a sidelink channel between the Remote UE and the source Relay UE, the quality threshold of the Uulink channel between the source Relay UE and the base station, and the quality threshold of the sillink channel between the Remote UE and the source Relay UE, and then determines whether to reselect the Relay UE for the Remote UE.

The trigger mode 6 is similar to the trigger mode one to four, and therefore details are omitted here.

After determining the quality of a Uulink channel between source Relay UE and a base station, the quality of a sidelink channel between Remote UE and the source Relay UE, the quality threshold of the Uulink channel between the source Relay UE and the base station and the quality threshold of the sidelink channel between the Remote UE and the source Relay UE, the Remote UE judges whether to reselect the Relay UE according to the information.

Optionally, the Remote UE determines whether the quality of a Uulink channel between the source Relay UE and the base station is greater than a set Uulink channel quality threshold, and whether the quality of a sidelink channel between the Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold, if so, the currently connected source Relay UE is maintained; otherwise, the Relay UE is reselected aiming at the Remote UE.

In specific implementation, only when the quality of a Uulink channel between source Relay UE and a base station is greater than a set Uulink channel quality threshold and the quality of a sidelink channel between Remote UE and source Relay UE is greater than a set sidelink channel quality threshold, it is determined that the source Relay UE can maintain Relay capability, and the Remote UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. This may make the communication between the Remote UE and the currently connected Relay UE more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

For example: the base station determines that the quality threshold of a sidelink channel between Remote UE and source Relay UE is 24; the Uulink channel quality threshold between the source Relay UE and the base station is 20.

If the quality of the Ullink channel between the source Relay UE and the base station is determined to be 19, and the quality of the sidelink channel between the Relay UE and the source Relay UE is determined to be 26, because the quality of the Ullink channel between the source Relay UE and the base station is less than the threshold of the Ullink channel quality, the Relay UE is reselected for the Relay UE.

And a triggering mode 7, judging whether to reselect the Relay UE according to the residual energy of the source Relay UE and the load of the source Relay UE by the Remote UE.

Firstly, the Remote UE needs to determine the residual energy of the source Relay UE, the load of the source Relay UE, the residual energy threshold of the source Relay UE, and the load threshold of the source Relay UE, and then determines whether to perform reselection of the Relay UE for the Remote UE.

The method for determining the residual energy of the source Relay UE, the load of the source Relay UE, the residual energy threshold of the source Relay UE, and the load threshold of the source Relay UE by the Remote UE in the trigger mode 7 is similar to the first to fourth trigger modes, and therefore description is omitted.

After determining the residual energy of the source Relay UE, the load of the source Relay UE, the residual energy threshold of the source Relay UE and the load threshold of the source Relay UE, the Remote UE will determine whether to reselect the Relay UE for the Remote UE according to the determined information.

Optionally, the Remote UE determines whether the residual energy of the source Relay UE is greater than a set source residual energy threshold, and whether the load of the source Relay UE is less than a set load threshold, and if so, maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE.

In specific implementation, only when the residual energy of the source Relay UE is greater than a set source residual energy threshold and the load of the source Relay UE is less than a set load threshold, determining that the source Relay UE can maintain the Relay capability, and maintaining the currently connected source Relay UE by the Remote UE; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, the Relay UE can be triggered and reselected in time under the condition that the residual energy of the source Relay UE is too low or the source Relay UE is overloaded, and the communication between the Relay UE and the Relay UE is more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

For example: the residual energy threshold of the source Relay UE determined by the base station is 50% of electric quantity; the load threshold for the source Relay UE is 3 UEs.

If the residual energy of the source Relay UE is determined to be 70% of electric quantity, and the source Relay UE loads 2 UEs, the source Relay UE currently connected with the Remote UE is maintained because the residual energy of the source Relay UE is greater than a residual energy threshold value and the load of the source Relay UE is less than a load threshold value.

And a triggering mode 8, judging whether to reselect the Relay UE by the Remote UE according to the residual energy of the source Relay UE and the Uulink channel quality between the source Relay UE and the base station.

Firstly, the Remote UE needs to determine the residual energy of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, the residual energy threshold of the source Relay UE, and the uuink channel quality threshold between the source Relay UE and the base station, and then determines whether to reselect the Relay UE for the Remote UE.

The method for determining the residual energy of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, the residual energy threshold of the source Relay UE, and the uuink channel quality threshold between the source Relay UE and the base station by the Remote UE in the trigger mode 8 is similar to the trigger modes one to four, and therefore, the description is omitted.

After determining the residual energy of the source Relay UE, the Ulink channel quality between the source Relay UE and the base station, the residual energy threshold of the source Relay UE and the Ulink channel quality threshold between the source Relay UE and the base station, the RemoteUE will determine whether to reselect the Relay UE for the Remote UE according to the determined information.

Optionally, the Remote UE determines whether the residual energy of the source Relay UE is greater than a set source residual energy threshold, and whether the Uulink channel quality between the source Relay UE and the base station is greater than a set Uulink channel quality threshold, and if so, maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE.

In specific implementation, only when the residual energy of the source Relay UE is greater than a set source residual energy threshold and the uuink channel quality between the source Relay UE and the base station is greater than a set uuink channel quality threshold, it is determined that the source Relay UE can maintain the Relay capability, and the Remote UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, the Remote UE can be triggered to reselect the Relay UE in time under the condition that the residual energy of the source Relay UE is too low or mutual data transmission cannot be carried out between the source Relay UE and the base station, and the communication between the Remote UE and the Relay UE can be more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

For example: the residual energy threshold of the source Relay UE determined by the base station is 50% of electric quantity; the Uulink channel quality threshold between the source Relay UE and the base station is 20.

If the residual energy of the source Relay UE is determined to be 70% of electric quantity and the Uulink channel quality between the source Relay UE and the base station is determined to be 19, the Relay UE is reselected aiming at the Relay UE because the Uulink channel quality between the source Relay UE and the base station is less than a Uulink channel quality threshold.

And 9, the Remote UE judges whether to reselect the Remote UE according to the load of the source Remote UE and the Uulink channel quality between the source Remote UE and the base station.

Firstly, the Remote UE needs to determine the load of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, the load threshold of the source Relay UE, and the uuink channel quality threshold between the source Relay UE and the base station, and then determines whether to reselect the Relay UE for the Remote UE.

The method for determining the load of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, the load threshold of the source Relay UE, and the uuink channel quality threshold between the source Relay UE and the base station by the Remote UE in the trigger mode 8 is similar to the first to fourth trigger modes, and therefore, the description is omitted.

After determining the load of the source Relay UE, the Ulink channel quality between the source Relay UE and the base station, the load threshold of the source Relay UE and the Ulink channel quality threshold between the source Relay UE and the base station, the Remote UE will determine whether to reselect the Relay UE for the Remote UE according to the determined information.

Optionally, the Remote UE determines whether the load of the source Relay UE is smaller than a set load threshold, and whether the Uulink channel quality between the source Relay UE and the base station is greater than a set Uulink channel quality threshold, if so, the currently connected source Relay UE is maintained; otherwise, the Relay UE is reselected aiming at the Remote UE.

In specific implementation, only when the load of the source Relay UE is smaller than a set load threshold and the quality of a Uulink channel between the source Relay UE and a base station is larger than a set Uulink channel quality threshold, determining that the source Relay UE can maintain the Relay capability and the Remote UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, the Relay UE can be triggered and reselected in time under the condition that the source Relay UE is overloaded or data transmission cannot be carried out between the source Relay UE and the base station, and the communication between the Relay UE and the Relay UE can be more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

For example: the load threshold value of source Relay UE determined by the base station is 3 UE; the Uulink channel quality threshold between the source Relay UE and the base station is 20.

If the load of the source Relay UE is determined to be 4 UEs and the Uulink channel quality between the source Relay UE and the base station is 19, because the load of the source Relay UE is greater than a set load threshold value, and the Uulink channel quality between the source Relay UE and the base station is less than the Uulink channel quality threshold value, the Relay UE is reselected.

And the triggering mode 10, the Remote UE judging whether to reselect the Remote UE for the Remote UE according to the residual energy of the source Remote UE, the load of the source Remote UE and the sidelink channel quality between the Remote UE and the source Remote UE.

Firstly, the Remote UE needs to determine the residual energy of the source Relay UE, the load of the source Relay UE, the sidelink channel quality between the Remote UE and the source Relay UE, the residual energy threshold of the source Relay UE, the load threshold of the source Relay UE, and the sidelink channel quality threshold between the Remote UE and the source Relay UE, and then determines whether to reselect the Relay UE for the Remote UE.

The method for determining the residual energy of the source Relay UE, the load of the source Relay UE, the sidelink channel quality between the Relay UE and the source Relay UE, the residual energy threshold of the source Relay UE, the load threshold of the source Relay UE, and the sidelink channel quality threshold between the Relay UE and the source Relay UE in the triggering method 10 is similar to the triggering method one to four, and therefore description is omitted.

After determining the residual energy of the source Relay UE, the load of the source Relay UE, the sidelink channel quality between the Relay UE and the source Relay UE, the residual energy threshold of the source Relay UE, the load threshold of the source Relay UE and the sidelink channel quality threshold between the Relay UE and the source Relay UE, the Relay UE will judge whether to reselect the Relay UE for the Relay UE according to the determined information.

Optionally, the Remote UE determines whether the residual energy of the source Relay UE is greater than a set source residual energy threshold, and whether the load of the source Relay UE is less than a set load threshold, and whether the quality of the sidelink channel between the Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold, if so, the currently connected source Relay UE is maintained; otherwise, the Relay UE is reselected aiming at the Remote UE.

In specific implementation, only when the residual energy of the source Relay UE is greater than a set source residual energy threshold, the load of the source Relay UE is less than a set load threshold, and the sidelink channel quality between the Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold, it is determined that the source Relay UE can maintain the Relay capability, and the Remote UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, when the residual energy of the source Relay UE is too low, or the source Relay UE is overloaded, or the sidelink channel quality between the Relay UE and the source Relay UE is poor, the Relay UE is triggered to reselect in time, so that the communication between the Relay UE and the Relay UE is more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

For example: the residual energy threshold of the source Relay UE determined by the base station is 50% of electric quantity; the load threshold of the source Relay UE is 3 UEs; the sidelink channel quality threshold between the Remote UE and the source Relay UE is 24.

If the residual energy of the source Relay UE is determined to be 70% of electric quantity, the source Relay UE loads 2 UEs, and when the quality of a sidelink channel between the Relay UE and the source Relay UE is 25, the source Relay UE currently connected with the Relay UE is maintained because the load of the source Relay UE is smaller than a load threshold.

And the triggering mode 11, the Remote UE judges whether to reselect the Remote UE according to the residual energy of the source Remote UE, the Uulink channel quality between the source Remote UE and the base station and the sidelink channel quality between the Remote UE and the source Remote UE.

Firstly, the Remote UE needs to determine the residual energy of the source Relay UE, the Uulink channel quality between the source Relay UE and the base station, the sidelink channel quality between the Remote UE and the source Relay UE, the residual energy threshold of the source Relay UE, the Uulink channel quality threshold between the source Relay UE and the base station, and the sidelink channel quality threshold between the Remote UE and the source Relay UE, and then determines whether to reselect the Relay UE for the Remote UE.

The method for determining the residual energy of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, the sidelink channel quality between the Relay UE and the source Relay UE, the residual energy threshold of the source Relay UE, the uuink channel quality threshold between the source Relay UE and the base station, and the sidelink channel quality threshold between the Relay UE and the source Relay UE in the triggering method 8 is similar to the triggering method one to four, and therefore description is omitted.

After determining the residual energy of the source Relay UE, the Ulink channel quality between the source Relay UE and the base station, the sidelink channel quality between the Relay UE and the source Relay UE, the residual energy threshold of the source Relay UE, the Ulink channel quality threshold between the source Relay UE and the base station, and the sidelink channel quality threshold between the Relay UE and the source Relay UE, the Relay UE will determine whether to reselect the Relay UE for the Relay UE according to the determined information.

Optionally, the Remote UE determines whether the residual energy of the source Relay UE is greater than a set source residual energy threshold, whether the Uulink channel quality between the source Relay UE and the base station is greater than a set Uulink channel quality threshold, and whether the sidelink channel quality between the Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold, if so, the currently connected source Relay UE is maintained; otherwise, the Relay UE is reselected aiming at the Remote UE.

In specific implementation, only when the residual energy of the source Relay UE is greater than a set source residual energy threshold, and the Uulink channel quality between the source Relay UE and the base station is greater than a set Uulink channel quality threshold, and whether the sidelink channel quality between the Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold between the source Relay UEs, it is determined that the source Relay UE can maintain the Relay capability, and the Remote UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, the Relay UE is triggered to reselect under the condition that the residual energy of the Relay UE is too low, or the mutual data transmission between the source Relay UE and the base station cannot be carried out, or the data transmission between the Relay UE and the source Relay UE cannot be carried out, so that the communication between the Relay UE and the Relay UE is more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

For example: the residual energy threshold of the source Relay UE determined by the base station is 50% of electric quantity; the quality threshold of the Uulink channel between the source Relay UE and the base station is 20, and the quality threshold of the sidelink channel between the Remote UE and the source Relay UE is 15.

If the residual energy of the source Relay UE is determined to be 70% of electric quantity, the quality of a Uulink channel between the source Relay UE and the base station is 19, and the quality of a sidelink channel between the Relay UE and the source Relay UE is 24, the Relay UE is reselected for the Relay UE because the quality of the Uulink channel between the source Relay UE and the base station is less than a threshold value of the Uulink channel quality.

The triggering mode 12 and the Remote UE judge whether to reselect the Remote UE according to the load of the source Remote UE, the Uulink channel quality between the source Remote UE and the base station and the sidelink channel quality between the Remote UE and the source Remote UE.

Firstly, the Remote UE needs to determine the load of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, the sidelink channel quality between the Remote UE and the source Relay UE, the load threshold of the source Relay UE, the uuink channel quality threshold between the source Relay UE and the base station, and the sidelink channel quality threshold between the Remote UE and the source Relay UE, and then determines whether to reselect the Relay UE for the Remote UE.

The method for determining the load of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, the sidelink channel quality between the Relay UE and the source Relay UE, the load threshold of the source Relay UE, the uuink channel quality threshold between the source Relay UE and the base station, and the sidelink channel quality threshold between the Relay UE and the source Relay UE in the triggering method 8 is similar to the triggering method one to four, and therefore description is omitted.

After determining the load of the source Relay UE, the Ulink channel quality between the source Relay UE and the base station, the sidelink channel quality between the Relay UE and the source Relay UE, the load threshold of the source Relay UE, the Ulink channel quality threshold between the source Relay UE and the base station, and the sidelink channel quality threshold between the Relay UE and the source Relay UE, the Relay UE will determine whether to reselect the Relay UE for the Relay UE according to the determined information.

Optionally, the Remote UE determines whether the load of the source Relay UE is smaller than a set load threshold, and whether the Uulink channel quality between the source Relay UE and the base station is greater than a set Uulink channel quality threshold, and whether the sidelink channel quality between the Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold between the source Relay UEs, if so, the currently connected source Relay UE is maintained; otherwise, the Relay UE is reselected aiming at the Remote UE.

In specific implementation, only when the load of the source Relay UE is smaller than a set load threshold, the quality of a Uulink channel between the source Relay UE and the base station is greater than a set Uulink channel quality threshold, and the quality of a sidelink channel between the Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold, it is determined that the source Relay UE can maintain the Relay capability, and the Remote UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, the Relay UE can be triggered and reselected in time under the condition that the source Relay UE is overloaded, or data transmission cannot be carried out between the source Relay UE and the base station, or data transmission cannot be carried out between the Relay UE and the source Relay UE, so that the communication between the Relay UE and the Relay UE is more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

For example: the load threshold value of source Relay UE determined by the base station is 3 UE; the quality threshold of a Uulink channel between source Relay UE and a base station is 20; the sidelink channel quality threshold between the Remote UE and the source Relay UE is 24.

If the load of the source Relay UE is determined to be 4 UEs, the quality of a Uulink channel between the source Relay UE and the base station is 19, and the quality of a sidelink channel between the Relay UE and the source Relay UE is 25, because the load of the source Relay UE is greater than a set load threshold value, and the quality of the Uulink channel between the source Relay UE and the base station is less than the threshold value of the Uulink channel quality, the Relay UE is reselected for the Relay UE.

And a triggering mode 13, the Remote UE judging whether to reselect the Remote UE according to the residual energy of the source Relay UE, the load of the source Relay UE and the Uulink channel quality between the source Relay UE and the base station.

Firstly, the Remote UE needs to determine the residual energy of the source Relay UE, the load of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, the residual energy threshold of the source Relay UE, the load threshold of the source Relay UE, and the uuink channel quality threshold between the source Relay UE and the base station, and then determines whether to reselect the Relay UE for the Remote UE.

The method for determining the residual energy of the source Relay UE, the load of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, the residual energy threshold of the source Relay UE, the load threshold of the source Relay UE, and the uuink channel quality threshold between the source Relay UE and the base station by the Remote UE in the triggering method 13 is similar to the triggering method one to four, and therefore, description is omitted.

After determining the residual energy of the source Relay UE, the load of the source Relay UE, the Uulink channel quality between the source Relay UE and the base station, the residual energy threshold of the source Relay UE, the load threshold of the source Relay UE and the Uulink channel quality threshold between the source Relay UE and the base station, the Remote UE will determine whether to reselect the Relay UE according to the determined information.

Optionally, the Remote UE determines whether the residual energy of the source Relay UE is greater than a set source residual energy threshold, and whether the load of the source Relay UE is less than a set load threshold, and whether the quality of the Uulink channel between the source Relay UE and the base station is greater than a set Uulink channel quality threshold, if so, the currently connected source Relay UE is maintained; otherwise, the Relay UE is reselected aiming at the Remote UE.

In specific implementation, only when the residual energy of the source Relay UE is greater than a set source residual energy threshold, the load of the source Relay UE is less than a set load threshold, and the quality of a Uulink channel between the source Relay UE and a base station is greater than a set Uulink channel quality threshold, it is determined that the source Relay UE can maintain the Relay capability, and the Remote UE maintains the currently connected source Relay UE; otherwise, the RelayUE is reselected aiming at the Remote UE. Therefore, the Relay UE can be triggered and reselected in time under the condition that the residual energy of the source Relay UE is too low, or the source Relay UE is overloaded, or data transmission cannot be carried out between the source Relay UE and the base station, so that the communication between the Relay UE and the Relay UE is more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

For example: the residual energy threshold of the source Relay UE determined by the base station is 50% of electric quantity; the load threshold of the source Relay UE is 3 UEs; the Uulink channel quality threshold between the source Relay UE and the base station is 20.

If the residual energy of the source Relay UE is determined to be 70% of electric quantity, the source Relay UE loads 2 UEs, and when the Ullink channel quality threshold between the source Relay UE and the base station is 22, the source Relay UE currently connected with the Remote UE is maintained because the residual energy of the source Relay UE is greater than the residual energy threshold, the load of the source Relay UE is less than the load threshold, and the Ullink channel quality between the source Relay UE and the base station is greater than the set Ullink channel quality threshold.

And the triggering mode 14, the Remote UE judging whether to reselect the Remote UE according to the residual energy of the source Remote UE, the load of the source Remote UE, the Uulink channel quality between the source Remote UE and the base station and the sidelink channel quality between the Remote UE and the source Remote UE.

Firstly, the Remote UE needs to determine the residual energy of the source Relay UE, the load of the source Relay UE, the Uulink channel quality between the source Relay UE and the base station, the sidelilink channel quality between the Remote UE and the source Relay UE, the residual energy threshold of the source Relay UE, the load threshold of the source Relay UE, the Uulink channel quality threshold between the source Relay UE and the base station, and the sillink channel quality threshold between the Remote UE and the source Relay UE, and then determines whether to reselect the Relay UE for the Remote UE.

The method for determining the residual energy of the source Relay UE, the load of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, the sidelink channel quality between the Relay UE and the source Relay UE, the residual energy threshold of the source Relay UE, the load threshold of the source Relay UE, the uuink channel quality threshold between the source Relay UE and the base station, and the sidelink channel quality threshold between the Relay UE and the source Relay UE in the triggering method 14 is similar to the triggering method one to four, and therefore description is omitted.

After determining the residual energy of the source Relay UE, the load of the source Relay UE, the Uulink channel quality between the source Relay UE and the base station, the sidelink channel quality between the Relay UE and the source Relay UE, the residual energy threshold of the source Relay UE, the load threshold of the source Relay UE, the Uulink channel quality threshold between the Source Relay UE and the base station, and the sidelink channel quality threshold between the Relay UE and the source Relay UE, the Relay UE will determine whether to reselect the Relay UE for the Relay UE according to the determined information.

Optionally, the Remote UE determines whether the residual energy of the source Relay UE is greater than a set source residual energy threshold, and whether the load of the source Relay UE is less than a set load threshold, and whether the quality of the Uulink channel between the source Relay UE and the base station is greater than a set Uulink channel quality threshold, and the quality of the sidelink channel between the Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold, if so, the currently connected source Relay UE is maintained; otherwise, the Relay UE is reselected aiming at the Remote UE.

In specific implementation, only when the residual energy of the source Relay UE is greater than a set source residual energy threshold, the load of the source Relay UE is less than a set load threshold, the quality of a Uulink channel between the source Relay UE and a base station is greater than a set Uulink channel quality threshold, and the quality of a sidelink channel between the Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold, it is determined that the source Relay UE can maintain the Relay capability, and the Remote UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, the Relay UE can be triggered and reselected in time under the condition that the residual energy of the Relay UE is too low, or the source Relay UE is overloaded, or data transmission cannot be performed between the source Relay UE and the base station, or data transmission cannot be performed between the Relay UE and the source Relay UE, so that the communication between the Relay UE and the Relay UE is more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

For example: the residual energy threshold of the source Relay UE determined by the base station is 50% of electric quantity; the load threshold of the source Relay UE is 3 UEs; the quality threshold of a Uulink channel between source Relay UE and a base station is 20; the sidelink channel quality threshold between the Remote UE and the source Relay UE is 24.

If the residual energy of the source Relay UE is determined to be 70% of electric quantity, the source Relay UE loads 2 UEs, the Ullink channel quality threshold between the source Relay UE and the base station is 22, and the sidelink channel quality threshold between the Remote UE and the source Relay UE is 25, the source Relay UE currently connected is maintained because the residual energy of the source Relay UE is greater than the residual energy threshold, the load of the source Relay UE is less than the load threshold, the Ullink channel quality between the source Relay UE and the base station is greater than the set Ullink channel quality threshold, and the sillink channel quality between the Remote UE and the source Relay UE is greater than the set sillink channel quality threshold.

After the Remote UE judges whether Relay UE is reselected aiming at the Remote UE according to the reselection information, if the Relay UE is determined to need to be reselected aiming at the Remote UE, further reselecting a UE for the Remote UE as a target Relay UE of the Remote UE.

When determining to select and determine the target Relay UE of the Relay UE, the Relay UE may determine the target Relay UE according to the information for selecting the target Relay UE, or the base station may determine the target Relay UE according to the information for selecting the target Relay UE.

And if the Remote UE determines the target Relay UE according to the information for selecting the target Relay UE.

Optionally, if it is determined that Relay UE needs to be reselected for the Relay UE, the Relay UE determines information for selecting a target Relay UE according to measurement parameters configured by the base station, selects the target Relay UE according to the information for selecting the target Relay UE, and notifies the base station of the selected target Relay UE.

The measurement parameters configured by the base station include, but are not limited to, the following part or all of:

the UE-based Relay protection method includes that ID of a neighbor cell base station, link quality of Uulink between the Remote UE and the neighbor cell base station, id of a candidate Relay UE, Sidelink link quality between user planes of the candidate Relay UE and the Remote UE, cell id of a cell to which the candidate Relay UE belongs, Uulink link quality between the candidate Relay UE and the base station, residual electric quantity of the candidate Relay UE and load of the candidate Relay UE are measured by the Remote UE.

All the parameters can be directly measured and obtained by Remote UE; and all candidate Relay UEs send parameter information such as self id, Sidelink link quality between the Relay UEs and user interfaces of the Relay UEs, self cell id, self Relay UE residual electric quantity, self Relay UE load and the like to the Relay UEs.

After Relay UE is selected for the Relay UE, the Relay UE determines that no available Relay UE exists, and selects an available base station according to the id of the adjacent cell base station measured by the Relay UE and the link quality of the adjacent cell base station Uulink, and accesses the base station to perform data transmission.

The id of the candidate Relay UE in the measurement parameters is used for informing the Remote UE of the selected target Relay UE after the target Relay UE is determined; the Sidelink link quality of the candidate Relay UE, the cell id of the candidate Relay UE, the Uulink link quality of the candidate Relay UE, the residual capacity of the Relay UE and the load of the Relay UE are all considered factors for selecting the Relay UE.

Wherein the information for selecting the target Relay UE includes part or all of the following:

the remaining energy of the candidate Relay UE, the load of the candidate Relay UE, the first channel quality between the candidate Relay UE and the Remote UE, the second channel quality between the candidate Relay UE and the base station, and the ID of the cell to which the candidate Relay UE belongs.

In the method, the Relay UE selects the target Relay UE according to the information for selecting the target Relay UE, and because various influence factors which can influence the Relay capability of the Relay UE, such as the residual energy of the Relay UE, the load of the Relay UE, the sidelink channel quality between the Relay UE and the Relay UE, the Uulink channel quality between the Relay UE and a base station, the ID of the cell to which the Relay UE belongs, and the like are taken into consideration when the target Relay UE is selected, the Relay UE with the most stable Relay capability can be selected as the target Relay UE of the Relay UE, and the system stability can be improved.

Wherein the candidate Relay UEs may be all UEs that the Relay UE can detect; or preliminary screening may be performed before selecting a target Relay UE for the Remote UE.

Wherein the first channel quality between the candidate Relay UE and the Remote UE refers to the sidelink channel quality between the candidate Relay UE and the Remote UE, and the second channel quality between the candidate Relay UE and the base station refers to the Uulink channel quality between the candidate Relay UE and the base station.

Residual energy of candidate Relay UE: if the residual energy of Relay UE selected by the Remote UE is too low, the Relay UE selected by the Remote UE may quickly fail to continue to provide the Relay service due to energy exhaustion, which may cause the Relay UE of the Remote UE to perform fast handover, and thus may not stably provide the Relay service for the Remote UE.

Load of candidate Relay UE: when Relay UE is selected for Remote UE, if the load of the Relay UE selected for the Remote UE is too large, a situation that the Relay UE cannot stably provide Relay service for the Remote UE due to the too large load may occur, and even network interruption may be caused.

First channel quality between candidate Relay UE and Remote UE: when Relay UE is selected for Remote UE, if the first channel quality between the Relay UE selected for the Remote UE and the Remote UE cannot satisfy the set condition, Relay service cannot be provided for the Remote UE, that is, data transmission cannot be performed.

Second channel quality between candidate Relay UE and base station: when Relay UE is selected for Remote UE, if the second channel quality between the Relay UE selected for the Remote UE and the base station cannot satisfy the set condition, data transmission cannot be performed between the Relay UE and the base station, and Relay service cannot be provided for the Remote UE.

When the selected Relay UE and the Remote UE belong to the same cell, the selected Relay UE can more stably provide Relay service for the Remote UE, and power consumption caused by soul interaction can be reduced.

The first method is as follows:

the base station sets a threshold value of each parameter in the information for selecting the target Relay UE, compares each parameter in the information for selecting the target Relay UE of the candidate Relay UE with the set threshold value, and selects the candidate Relay UE with all the conditions better than the set threshold value as the target Relay UE.

For example: the base station sets the residual energy threshold value as 50% electric quantity, the load threshold value as 3 UE, the sidelink channel quality as 20 and the Uulink channel quality as 20; and the ID of the cell to which UE1 belongs is the same as the ID of the cell to which the Remote UE belongs.

Then if there are 2 candidate Relay UEs for the Remote UE, namely Relay UE1 and Relay UE2, and the measurement results are:

the remaining energy of Relay UE1 is 60% capacity, the load of Relay UE1 is 2, the sidelink channel quality between Relay UE1 and Remote UE is 24, and the Uulink channel quality between Relay UE1 and base station is 16; and the ID of the cell to which the RelayUE UE1 belongs is the same as the ID of the cell to which the Remote UE belongs;

the remaining energy of Relay UE2 is 70% of capacity, the load of Relay UE2 is 1, the first channel quality between Relay UE2 and Remote UE is 22, and the second channel quality between Relay UE2 and base station is 22; and the ID of the cell to which the Relay UE2 belongs is the same as the ID of the cell to which the Remote UE belongs.

The residual energy of the Relay UE1 is greater than a set threshold, the load is less than a load threshold, the sidelink channel quality is greater than the set threshold, and the ID of the cell to which the Relay UE1 belongs is the same as the ID of the cell to which the Relay UE belongs, but the Uulink channel quality between the Relay UE1 and the base station is less than the set threshold, so the Relay UE1 cannot be the target Relay UE of the Relay UE;

residual energy of Relay UE2 is greater than a set threshold, load is less than a load threshold, sidelink channel quality is greater than a set threshold, Uulink channel quality is greater than a set threshold, and the ID of the cell to which Relay UE1 belongs is the same as the ID of the cell to which Relay UE belongs, so Relay UE2 can be used as target Relay UE of the Relay UE;

the second method comprises the following steps: and determining the priority factors of the candidate Relay UEs according to the information corresponding to the candidate Relay UEs in the information for selecting the target Relay UEs and preset weights, and selecting the candidate Relay UEs corresponding to the maximum priority factors as the target Relay UEs.

In specific implementation, the embodiment of the invention introduces a priority factor algorithm of a candidate Relay UE:

priority factor of candidate Relay UE i:

P_{relay_i}＝A×h_{sidelink_i}+B×h_{uulink_i}+C×h_{battery_i}+D×h_{load_i}+E×h_{cell_i}；

wherein, P_{relay_i}A priority factor representing a Relay UE i as a candidate;

h_{sidelink_i}representing a link quality normalization value of Sidelink between Relay UE i which are candidates between Remote UEs, wherein A is a weight corresponding to the link quality of Sidelink;

h_{uulink_i}representing a link quality normalization value of a candidate Relay UE i and a base station Uulink, wherein B is a weight corresponding to the link quality of the Uulink;

h_{battery_i}representing a residual energy normalization value of a candidate Relay UE i, wherein C is a weight corresponding to the residual energy;

h_{load_i}representing the load normalization value of the candidate Relay UE i, wherein D is the weight corresponding to the load;

h_{cell_i}and E is the weight corresponding to the residual energy.

The weighting weight related to the embodiment of the invention can be set according to the actual network condition and the service requirement of the Remote UE.

For example: determining a candidate Relay UE of the Remote UE as UE1, and determining:

the UE1 residual energy normalization value is 0.5, with a corresponding weight of 0.3;

the UE1 has a load normalization value of 0.4 and a corresponding weight of 0.2;

the sidelink channel quality normalization value of the UE1 is 0.75, and the corresponding weight is 0.3;

the Uulink channel quality normalization value of the UE1 is 0.5, and the corresponding weight is 0.1;

the ID normalization value of the cell to which the UE1 belongs is 1, and the corresponding weight is 0.1.

Then the priority factor of the UE1 is determined to be:

P_{relay_1}＝A×h_{sidelink_1}+B×h_{uulink_1}+C×h_{battery_1}+D×h_{load_1}+E×h_{cell_1}＝0.75×0.3+0.5×0.1+0.5×0.3+0.4×0.2+1×0.1＝0.605；

wherein, P_{relay_1}A priority factor represented as UE 1;

h_{sidelink_1}the link quality normalization value of Sidelink between UE1 between Remote UE is represented, and A is the weight corresponding to the link quality of Sidelink;

h_{uulink_1}the normalized value of the link quality of the UE1 and the base station Uulink is shown, and B is the weight corresponding to the link quality of the Uulink;

h_{battery_1}representing the normalized value of the residual energy of the UE1, wherein C is the weight corresponding to the residual energy;

h_{load_1}represents the normalized value of the UE1, D being the weight corresponding to the load;

h_{cell_1}the ID normalization value indicating the cell to which the UE1 belongs, and E is a weight corresponding to the remaining energy.

For example: if there are 2 candidate Relay UEs for the Remote UE, these are Relay UE1 and Relay UE2, and the calculation results are: if the priority factor of the Relay UE1 is 0.5 and the priority factor of the Relay UE2 is 0.6, the Relay UE2 is selected as the target Relay UE of the Remote UE.

Type 2, unidirectional type.

In the embodiment of the invention, the Remote UE judges whether to reselect the Remote UE for the Remote UE according to the performance information of the source Remote UE, or the performance information of the source Remote UE and the sidelink channel quality between the Remote UE and the source Remote UE.

In specific implementation, the base station may send a residual energy threshold to the Remote UE, and then the Remote UE receives the residual energy threshold, so that when determining whether to perform reselection of the Remote UE for the Remote UE, the Remote UE compares the residual energy of the source Remote UE with the residual energy threshold sent by the base station to determine whether to perform reselection of the Remote UE for the Remote UE.

The base station may send the residual energy threshold to the Remote UE when the Remote UE first selects the Relay UE, and then does not send the residual energy threshold repeatedly; the residual energy threshold may also be sent to the Remote UE each time a Relay UE is selected.

Furthermore, the remaining energy threshold may also be preconfigured to the Remote UE.

When a Remote UE establishes a connection with a base station through a source Relay UE, the Remote UE needs to determine the residual energy of the source Relay UE before determining whether to perform reselection of the Remote UE for the Remote UE according to the residual energy of the source Relay UE, so as to determine whether to perform reselection of the Remote UE for the Remote UE.

Optionally, the Remote UE receives the remaining energy sent by the base station.

In the method, a unidirectional sidelink transmission channel is arranged between the Remote UE and the source Relay UE, and the Remote UE only has the capability of sending data, so that the residual energy of the source Relay UE is sent to the base station through the source Relay UE and then sent to the Remote UE by the base station, and the Remote UE is enabled to acquire the residual energy of the source Relay UE.

In specific implementation, the Remote UE determines whether the residual energy of the source Relay UE is greater than a set residual energy threshold, and if so, maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, when the Remote UE judges whether to reselect the Remote UE for the Remote UE, when the Remote UE judges that the residual energy of the source Remote UE is greater than a set residual energy threshold value, the Remote UE determines that the residual energy of the source Remote UE is sufficient, can stably provide service for the Remote UE, and is connected with the source Remote UE; otherwise, determining that the energy of the currently connected source Relay UE is too low to provide service for the Relay UE well, and reselecting the Relay UE for the Relay UE. Therefore, when the residual energy of the source Relay UE connected with the Relay UE is too low, the Relay UE can be reselected and switched in time, the condition that the data transmission between the Relay UE and the base station is interrupted due to the energy exhaustion of the source Relay UE is avoided, the communication capability of the Relay UE is improved, and the system performance is improved.

For example: the residual energy threshold of source Relay UE of the Remote UE determined by the base station is 50% of electric quantity, and when the residual energy of the source Relay UE of the Remote UE is 35% of electric quantity, the Remote UE judges that the Relay UE reselects for the Remote UE because the residual energy of the source Relay UE is smaller than the residual energy threshold.

And 2, judging whether to reselect the Relay UE for the Relay UE by the Remote UE according to the load of the source Relay UE by the Remote UE.

First, the Remote UE needs to determine the load of the source Relay UE and a corresponding load threshold, and then determines whether to reselect the Relay UE for the Remote UE.

In specific implementation, the base station may send a load threshold to the Remote UE, and then the Remote UE receives the load threshold, so that when determining whether to perform reselection of the Remote UE for the Remote UE, the Remote UE compares the load of the source Relay UE with the set load threshold to determine whether to perform reselection of the Remote UE for the Remote UE.

The base station may send the load threshold to the Remote UE when the Remote UE first selects the Relay UE, and then does not send the load threshold repeatedly; the load threshold may also be sent to the Remote UE each time the Remote UE selects a Relay UE. In addition, the load threshold may also be preconfigured in the Remote UE.

After determining the load and the load threshold of the source Relay UE, the Relay UE judges whether to reselect the Relay UE for the Relay UE.

Optionally, the Remote UE receives a load of the source Relay UE sent by the base station.

In the method, the load of the source Relay UE may be sent to the base station by the source Relay UE first, and then sent to the Remote UE by the base station, so that the Remote UE acquires the residual energy and the channel quality of the source Relay UE.

After determining the load and the load threshold of the source Relay UE, judging according to the received load of the source Relay UE and the set load threshold, and determining whether to reselect the Relay UE for the Remote UE.

Optionally, the Remote UE determines whether the load of the source Relay UE is greater than a load threshold, and if so, maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, when the Remote UE takes the load of the source Relay UE as a judgment basis for judging whether to reselect the Relay UE aiming at the Remote UE, the residual energy of the source Relay UE is determined to be sufficient only when the load of the source Relay UE is smaller than a set load threshold value, so that the service can be stably provided for the Remote UE, and the Remote UE is connected with the source Relay UE; otherwise, determining that the energy of the currently connected source Relay UE is too low to provide service for the Relay UE well, and reselecting the Relay UE for the Relay UE. Therefore, when the source Relay UE connected with the Relay UE is overloaded, the Relay UE can be reselected and switched in time, the condition that data transmission between the Relay UE and the base station is interrupted due to energy exhaustion of the source Relay UE is avoided, the communication capability of the Relay UE is improved, and the system performance is improved.

For example: the load threshold of source Relay UE connected with Remote UE determined by a base station is 4 UEs, currently, the load of the source Relay UE determined by the Remote UE to be connected is 3 UEs, and at the moment, the Remote UE determines that the load of the source Relay UE is smaller than the set load threshold, so that the Remote UE maintains the connected source Relay UE.

Firstly, the Remote UE needs to determine the Uulink channel quality between the source Relay UE and the base station and the corresponding Uulink channel quality threshold between the source Relay UE and the base station, and then determines whether to perform reselection of the Relay UE for the Remote UE.

In specific implementation, a base station sends a uuink channel quality threshold between a Relay UE and the base station to the Relay UE, and then the Relay UE receives the uuink channel quality threshold, so that when judging whether to perform reselection of the Relay UE for the Relay UE, the Relay UE compares the uuink channel quality between the Relay UE and the base station with the set uuink channel quality threshold to determine whether to perform reselection of the Relay UE for the Relay UE.

The base station can send the Uulink channel quality threshold to the Remote UE when the Remote UE selects the Relay UE for the first time, and then the Uulink channel quality threshold is not sent repeatedly; or sending the Uulink channel quality threshold to the Remote UE when the Remote UE selects the Relay UE each time. In addition, the uuink channel quality threshold may also be preconfigured in the Remote UE.

After determining the Uulink channel quality between the source Relay UE and the base station and the Uulink channel quality threshold value, the Relay UE judges whether to reselect the Relay UE for the Relay UE.

Optionally, the Remote UE receives the Uulink channel quality between the source Relay UE and the base station sent by the base station.

After the Uulink channel quality and the Uulink channel quality threshold between the source Relay UE and the base station are determined, judging according to the received Uulink channel quality and the Uulink channel quality threshold between the source Relay UE and the base station, and determining whether to reselect Relay UE for Remote UE.

In specific implementation, the Remote UE receives a residual energy threshold of the source Relay UE and a sidelink channel quality threshold between the Remote UE and the source Relay UE, which are sent by the base station. In this way, the Remote UE can obtain the residual energy threshold of the source Relay UE and the sidelink channel quality threshold between the Remote UE and the source Relay UE, and further, when it is determined whether to perform reselection of the Remote UE for the Remote UE, compare the sidelink channel quality between the Remote UE and the source Relay UE with the sidelink channel quality threshold, and compare the residual energy of the source Relay UE with the residual energy threshold to determine whether to perform reselection of the Remote UE for the Remote UE.

Optionally, the Remote UE receives the residual energy of the source Relay UE and the sidelink channel quality between the Remote UE and the source Relay UE, where the residual energy is sent by the base station.

In the method, the source Relay UE sends the residual energy of the source Relay UE and the sidelink channel quality between the Relay UE and the source Relay UE to the base station, and then the base station sends the residual energy and the sidelink channel quality to the Relay UE, so that when the sidelink between the Relay UE and the source Relay UE is of a unidirectional transmission type, the Relay UE can also obtain the residual energy of the source Relay UE and the sidelink channel quality between the Relay UE and the source Relay UE.

After determining the residual energy of the source Relay UE, the sidelink channel quality between the Relay UE and the source Relay UE, the residual energy threshold of the source Relay UE and the sidelink channel quality threshold, judging according to the above information, and determining whether to reselect the Relay UE for the Relay UE.

In the method, the currently connected source Relay UE is maintained only when the residual energy of the source Relay UE connected with the Remote UE and the sidelink channel quality between the Remote UE and the source Relay UE are both greater than the set threshold; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, when the residual energy of the source Relay UE is too low or the sidelink channel quality between the Relay UE and the source Relay UE is too low, a new Relay UE is selected and accessed, thereby avoiding the possibility of data transmission interruption between the Relay UE and the base station due to the source Relay UE being unable to maintain the Relay capability, improving the communication capability of the Relay UE and improving the system performance.

For example: the base station determines that the quality threshold of a sidelink channel between the Remote UE and the source Relay UE is 25; the remaining energy threshold for the source Relay UE is 50% of battery.

If the residual energy of the source Relay UE is determined to be 35% of electric quantity, and the sidelink channel quality between the Relay UE and the source Relay UE is determined to be 22, the Relay UE is reselected for the Relay UE because the residual energy of the source Relay UE is smaller than a residual energy threshold value, and the sidelink channel quality between the Relay UE and the source Relay UE is smaller than a sidelink channel quality threshold value.

In the triggering mode 5, the Remote UE determines the load of the source Relay UE, the Sidelink channel quality between the Remote UE and the source Relay UE, the load threshold of the source Relay UE, and the Sidelink channel quality threshold are similar to those of the triggering mode in which the Sidelink is a unidirectional type, and thus, description is omitted.

For example: the base station determines that the quality threshold of a sidelink channel between Remote UE and source Relay UE is 24; the load threshold for the source Relay UE is 4 UEs.

If the load of the source Relay UE is determined to be 3 UEs and the sidelink channel quality between the Relay UE and the source Relay UE is determined to be 26, the load of the source Relay UE is smaller than a load threshold value, and the sidelink channel quality between the Relay UE and the source Relay UE is larger than a sidelink channel quality threshold value, so that the source Relay UE which is connected currently is maintained.

The Remote UE in the triggering mode 6 determines the quality of the uuink channel between the source Relay UE and the base station, the quality of the Sidelink channel between the Remote UE and the source Relay UE, the quality threshold of the uuink channel between the source Relay UE and the base station, and the quality threshold of the Sidelink channel between the Remote UE and the source Relay UE, which are similar to the triggering modes of the single-direction type of the Sidelink, and therefore are not described in detail.

After determining the quality of a Uulink channel between source Relay UE and a base station, the quality of a sidelink channel between Remote UE and the source Relay UE, the quality threshold of the Uulink channel between the source Relay UE and the base station, and the quality threshold of the sidelink channel between Remote UE and the source Relay UE, the Remote UE judges whether to reselect the Relay UE according to the information.

Optionally, the Remote UE determines whether the quality of a Uulink channel between the source Relay UE and the base station and the Remote UE are greater than a set Uulink channel quality threshold, and whether the quality of a sidelink channel between the Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold between the source Relay UEs, if so, the currently connected source Relay UE is maintained; otherwise, the Relay UE is reselected aiming at the Remote UE.

The method for determining the residual energy of the source Relay UE, the load of the source Relay UE, the residual energy threshold of the source Relay UE, and the load threshold of the source Relay UE by the Remote UE in the triggering method 7 is similar to the triggering method in which the sildelink is a unidirectional type, i.e., one to four triggering methods, and thus is not described in detail.

If the residual energy of the source Relay UE is determined to be 70% of electric quantity and the load of the source Relay UE is 2 UEs, the source Relay UE currently connected with the Remote UE is maintained because the residual energy of the source Relay UE is greater than a residual energy threshold value and the load of the source Relay UE is less than a load threshold value.

The method for determining the residual energy of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, the residual energy threshold of the source Relay UE, and the uuink channel quality threshold between the source Relay UE and the base station by the Remote UE in the triggering method 8 is similar to the triggering method of the single-direction type, i.e., one to four triggering methods, and therefore, the description is omitted.

In specific implementation, only when the residual energy of the source Relay UE is greater than a set source residual energy threshold and the uuink channel quality between the source Relay UE and the base station is greater than a set uuink channel quality threshold, it is determined that the source Relay UE can maintain the Relay capability, and the Remote UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, the Relay UE can be triggered and reselected in time under the condition that the residual energy of the source Relay UE is too low or mutual data transmission cannot be carried out between the source Relay UE and the base station, and the communication between the Relay UE and the Relay UE can be more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

The method for determining the load of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, the load threshold of the source Relay UE, and the uuink channel quality threshold between the source Relay UE and the base station by the Remote UE in the triggering method 8 is similar to the triggering method of the single-direction type of the sildelink, i.e., one to four triggering methods, and therefore, the description is omitted.

If the load of the source Relay UE is determined to be 4 UEs and the Uulink channel quality between the source Relay UE and the base station is 19, the Relay UE is reselected for the Remote UE because the load of the source Relay UE is greater than a set load threshold and the Uulink channel quality between the source Relay UE and the base station is less than the Uulink channel quality threshold.

The method for determining the residual energy of the source Relay UE, the load of the source Relay UE, the Sidelink channel quality between the Relay UE and the source Relay UE, the residual energy threshold of the source Relay UE, the load threshold of the source Relay UE, and the Sidelink channel quality threshold between the Relay UE and the source Relay UE by the Remote UE in the trigger mode 7 is similar to the one to four trigger modes in the case that the Sidelink is a unidirectional type, and therefore, description is omitted.

If the residual energy of the source Relay UE is determined to be 70% of electric quantity, the source Relay UE loads 2 UEs, and the sidelink channel quality between the Relay UE and the source Relay UE is 25, the source Relay UE currently connected with the Relay UE is maintained because the residual energy of the source Relay UE is greater than the residual energy threshold, the load of the source Relay UE is less than the load threshold, and the sidelink channel quality between the Relay UE and the source Relay UE is greater than the set sidelink channel quality threshold.

The method for determining the residual energy of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, the Sidelink channel quality between the Relay UE and the source Relay UE, the residual energy threshold of the source Relay UE, the uuink channel quality threshold between the source Relay UE and the base station, and the Sidelink channel quality threshold between the Relay UE and the source Relay UE by the Remote UE in the triggering method 8 is similar to the triggering method in which the Sidelink is a unidirectional type, i.e., one to four methods, and therefore, the description is omitted.

Optionally, the Remote UE determines whether the residual energy of the source Relay UE is greater than a set source residual energy threshold, whether the Uulink channel quality between the source Relay UE and the base station is greater than a set Uulink channel quality threshold, and whether the sidelink channel quality between the Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold between the source Relay UEs, if so, the currently connected source Relay UE is maintained; otherwise, the Relay UE is reselected aiming at the Remote UE.

The method for determining the load of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, the Sidelink channel quality between the Relay UE and the source Relay UE, the load threshold of the source Relay UE, the uuink channel quality threshold between the source Relay UE and the base station, and the Sidelink channel quality threshold between the Relay UE and the source Relay UE by the Relay UE in the triggering method 8 is similar to the triggering method of one to four in which the Sidelink is a unidirectional type, and therefore, description is omitted.

The method for determining the residual energy of the source Relay UE, the load of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, the residual energy threshold of the source Relay UE, the load threshold of the source Relay UE, and the uuink channel quality threshold between the source Relay UE and the base station by the Remote UE in the triggering method 13 is similar to the triggering method of one to four in the case of the single-direction type of the Sidelink, and therefore, the description is omitted.

In specific implementation, only when the residual energy of the source Relay UE is greater than a set source residual energy threshold, the load of the source Relay UE is less than a set load threshold, and the quality of a Uulink channel between the source Relay UE and a base station is greater than a set Uulink channel quality threshold, it is determined that the source Relay UE can maintain the Relay capability, and the Remote UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, the Relay UE can be triggered and reselected in time under the condition that the residual energy of the source Relay UE is too low, or the source Relay UE is overloaded, or data transmission cannot be carried out between the source Relay UE and the base station, so that the communication between the Relay UE and the Relay UE is more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

The method for determining the residual energy of the source Relay UE, the load of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, the Sidelink channel quality between the Relay UE and the source Relay UE, the residual energy threshold of the source Relay UE, the load threshold of the source Relay UE, the uuink channel quality threshold between the source Relay UE and the base station, and the Sidelink channel quality threshold between the Relay UE and the source Relay UE by the Remote UE in the trigger mode 14 is similar to the method for one to four triggers in which the Sidelink is in the unidirectional type, and therefore, the description is omitted.

If the residual energy of the source Relay UE is determined to be 70% of electric quantity, the source Relay UE loads 2 UEs, and the Uulink channel quality threshold between the source Relay UE and the base station is 22, the source Relay UE currently connected with the Relay UE is maintained because the residual energy of the source Relay UE is greater than the residual energy threshold, the load of the source Relay UE is less than the load threshold, the Uulink channel quality between the source Relay UE and the base station is greater than the set Uulink channel quality threshold, and the sidelink channel quality between the Relay UE and the source Relay UE is greater than the set sidelink channel quality threshold.

When the Sidelink between the Remote UE and the Relay UE is of a unidirectional type, the Remote UE cannot directly receive a message sent by the Relay UE at this time, and cannot directly measure and acquire relevant measurement parameters of candidate Relay UE, so all the parameters can only be measured and acquired by the Remote UE, such as the id of the neighboring cell base station and the link quality of the uuink between the Remote UE and the neighboring cell base station, the candidate Relay UE can only measure and acquire the id reported to the base station, the quality of the silink link between the Remote UE and the user interface of the Remote UE, the id of the cell to which the Remote UE belongs, the quality of the uuink link between the Remote UE and the base station, the remaining power of the Relay UE and the load of the Relay UE, and the base station forwards the information to the Relay UE.

And when the selected Relay UE and the Remote UE belong to the same cell, the selected Relay UE can more stably provide the Relay service for the Remote UE.

The first method is as follows:

priority factor of candidate Relay UE i:

wherein, P_{relay_i}A priority factor representing a Relay UE i as a candidate;

h_{cell_i}and E is the weight corresponding to the residual energy.

Then the priority factor of the UE1 is determined to be:

wherein, P_{relay_1}A priority factor represented as UE 1;

The timing diagram will now illustrate an embodiment of the present invention.

In a first scenario, as shown in fig. 2, a source Relay UE and a target Relay UE belong to the same eNB, and a Remote UE has the capability of receiving and transmitting in a sidelink at the same time, that is, an RRC sidelink between the Remote UE and the Relay UE is a bidirectional transmission type. Wherein, Relay UE1 is used as source Relay UE to which the Remote UE is connected; the Relay UE2 is selected as a target Relay UE by the Remote UE.

A flowchart of a method for reselecting a Relay UE according to an embodiment of the present invention is shown in fig. 3.

Step 300, data are sent and received between the Remote UE and the service base station eNB through Relay UE 1;

step 301, the Relay UE1 inserts its own performance information into the data periodically;

step 302, a serving base station eNB configures Relay UE reselection configuration for a Remote UE, wherein the Relay UE reselection configuration comprises a residual energy threshold;

step 303, the Remote UE determines whether to perform Relay UE reselection for the Remote UE according to the renewed information;

step 304, the Remote UE selects the target Relay UE according to the information for selecting the target Relay UE;

step 305, the Remote UE sends a Relay reselection request to the eNB, where the request message carries information of the Relay UE 2;

step 306, the eNB sends a Relay reselection request to a Relay UE2, where the request message carries information of a Remote UE;

step 307, Relay UE2 sends a Relay reselection confirm message to eNB;

step 308, the eNB sends a Relay reselection confirmation message to the Remote UE;

step 309, establishing PC5 connection between Remote UE and Relay UE 2;

step 310, establishing RRC connection between the Relay UE2 and the eNB;

step 311, disconnecting the PC5 between the Remote UE and the Relay UE 1;

step 312, the eNB performs RRC sidelink reconfiguration for the Remote UE via Relay UE 2;

step 313, the Remote UE and the eNB send and receive data through the Relay UE 2.

In a second scenario, as shown in fig. 4, the source Relay UE and the target Relay UE belong to different enbs, and the Remote UE has the capability of receiving and transmitting in sidelink at the same time, that is, the RRC sidelink between the Remote UE and the Relay UE is a bidirectional transmission type. The Relay UE1 serves as a source Relay UE to which the Relay UE is connected, and the eNB1 serves as a serving base station of the source Relay UE 1; the Relay UE2 is the target Relay UE reselected by the Remote UE, and the eNB2 is the serving base station of the target Relay UE 2.

A flowchart of a method for reselecting a Relay UE according to an embodiment of the present invention is shown in fig. 5.

Step 500, data are transmitted and received between the Remote UE and the eNB1 through the Relay UE 1;

step 501, the Relay UE1 inserts its own performance information into the data periodically;

step 502, eNB1 configures Relay reselection configuration for Remote UE, where the Relay reselection configuration includes a channel quality threshold and a residual energy threshold;

step 503, the Remote UE determines whether to perform Relay UE reselection for the Remote UE according to the re-information;

step 504, the Remote UE selects the target Relay UE according to the information for selecting the target Relay UE;

step 505, the Remote UE sends a Relay reselection request to the eNB1, and an eNB1 forwards the request to an eNB2, where the request message carries information of a Relay UE 2;

step 506, the eNB2 sends a Relay reselection request to the Relay UE2, where the request message carries information of the Remote UE;

in step 507, the Relay UE2 sends a Relay reselection confirm message to the eNB 2;

step 508, eNB2 sends a Relay reselection confirm message to the Remote UE;

step 509, establishing a PC5 connection between the Remote UE and the Relay UE 2;

step 510, establishing RRC connection between the Relay UE2 and the eNB 2;

step 511, disconnecting the PC5 between the Remote UE and the Relay UE 1;

step 512, eNB2 performs RRC sidelink reconfiguration for the Remote UE via Relay UE 2;

step 513, the Remote UE and the eNB2 transmit and receive data through the Relay UE 2.

In a third scenario, as shown in fig. 6, the source Relay UE and the target Relay UE belong to the same eNB, and the Remote UE only has a sidelink transmission capability, that is, the RRC sidelink between the Remote UE and the Relay UE is a unidirectional transmission type. The Relay UE1 serves as a source Relay UE to which the Relay UE is connected, and the eNB1 serves as a serving base station of the source Relay UE 1; the Relay UE2 is the target Relay UE reselected by the Remote UE, and the eNB2 is the serving base station of the target Relay UE 2.

A flowchart of a method for reselecting a Relay UE according to an embodiment of the present invention is shown in fig. 7.

Step 700, data is sent between the Remote UE and the eNB through Relay UE 1;

step 701, Relay UE1 measures performance information of Relay UE 1;

step 702, the Relay UE1 sends the measured RRC sidelink quality to the eNB;

step 703, the eNB sends the RRC sidelink quality reported by Relay UE1 to the Remote UE;

step 704, the Remote UE determines whether to perform Relay UE reselection for the Remote UE according to the re-information;

step 705, the Remote UE selects a target Relay UE according to the information for selecting the target Relay UE;

step 706, the Remote UE sends a Relay reselection request to the eNB, where the request message carries information of the Relay UE 2;

step 707, the eNB sends a Relay reselection request to the Relay UE2, where the request message carries information of the Relay UE 2;

step 708, the Relay UE2 sends a Relay reselection confirm message to the eNB;

step 709, the eNB sends a Relay reselection acknowledgement message to the Remote UE;

step 710, establishing PC5 connection between Remote UE and Relay UE 2;

step 711, establishing RRC connection between Relay UE2 and eNB;

step 712, disconnecting PC5 between Remote UE and Relay UE 1;

step 713, the eNB performs RRC sidelink reconfiguration for the Remote UE via Relay UE 2;

in step 714, the Remote UE and the eNB send data through the Relay UE 2.

In a fourth scenario, as shown in fig. 8, the source Relay UE and the target Relay UE belong to different enbs, and the Remote UE only has a sidelink transmission capability, that is, the RRC sidelink between the Remote UE and the Relay UE is of a unidirectional transmission type. The Relay UE1 serves as a source Relay UE to which the Relay UE is connected, and the eNB1 serves as a serving base station of the source Relay UE 1; the Relay UE2 is a target Relay UE reselected by the Remote UE, and the eNB2 is a serving base station of the target Relay UE 2.

A flowchart of a method for reselecting a Relay UE according to an embodiment of the present invention is shown in fig. 9.

Step 900, data is transmitted between the Remote UE and the eNB1 through the Relay UE 1;

step 901, Relay UE1 measures performance information of Relay UE 1;

step 902, Relay UE1 sends the measured RRC sidelink quality to eNB 1;

step 903, the eNB1 sends the RRC sidelink quality reported by the Relay UE1 to the Remote UE;

step 904, the Remote UE determines whether to perform Relay UE reselection for the Remote UE according to the re-information;

step 905, the Remote UE selects the target Relay UE according to the information for selecting the target Relay UE;

step 906, the Remote UE sends a Relay reselection request to the eNB1, and the request message is transferred to the eNB2 by the eNB1, where the request message carries information of the Relay UE 2;

step 907, the eNB2 sends a Relay reselection request to the Relay UE2, where the request message carries information of the Remote UE;

step 908, the Relay UE2 sends a Relay reselection confirm message to the eNB 2;

step 909, eNB2 sends Relay reselection confirm message to Remote UE;

step 910, establishing PC5 connection between Remote UE and Relay UE 2;

911, establishing RRC connection between the Relay UE2 and the eNB 2;

step 912, disconnecting the PC5 connection between the Remote UE and the Relay UE 1;

step 913, eNB2 performs RRC sidelink reconfiguration for the Remote UE via Relay UE 2;

step 914, data is transmitted between the Remote UE and the eNB2 through the Relay UE 2.

After determining that Relay UE reselection needs to be performed for the Remote UE through the steps, the Remote UE needs to further determine target Relay UE of the Remote UE.

As can be seen from the above example, when the source Relay UE and the target Relay UE are in different coverage areas of the base station, the operation processes thereof are substantially the same. In addition, when the Remote UE and the Relay UE are not in the same coverage area of the base station, the processing method is similar to the scheme, that is, the instruction information originally forwarded by one base station needs to be forwarded by two base stations.

As shown in fig. 10, an embodiment of the present invention further provides a method for reselecting a Relay UE, where the method includes:

step 1000, when a base station is connected with a Remote UE through a source Relay UE, reselecting information, wherein the reselecting information is performance information of the source Relay UE or the reselecting information includes the performance information of the source Relay UE and a first channel quality between the Remote UE and the source Relay UE; wherein the capability information of the source Relay UE includes part or all of the following: the residual energy of the source Relay UE, the load of the source Relay UE, and the quality of a second channel between the source Relay UE and the base station;

step 1001, the base station determines whether to perform reselection of Relay UE for the Remote UE according to the reselection information.

In the method, the base station judges according to the reselection message to determine whether to reselect the Relay UE for the Remote UE. Compared with the prior art, the embodiment of the invention judges according to the performance information of the source Relay UE, or the performance information of the source Relay UE and the first channel quality between the Relay UE and the source Relay UE, and determines whether to reselect the Relay UE for the Relay UE, so that the embodiment of the invention provides a scheme for triggering the reselection of one UE as the Relay UE, thereby improving the communication capability of the Relay UE and perfecting the system performance.

When the base station determines whether to reselect Relay UE for the Relay UE and realizes data transmission between the Relay UE and the base station through the Relay UE, an RRCSidelink needs to be established between the Relay UE and the Relay UE, however, the specific flow of reselecting the Relay UE of the Relay UE is not influenced by the connection type of the RRC sidelink.

In the embodiment of the invention, a base station judges whether to reselect the Relay UE according to the performance information of the Source Relay UE, or the performance information of the Source Relay UE and the sidelink channel quality between the Relay UE and the Source Relay UE.

And in the triggering mode 1, the base station judges whether to reselect the Relay UE aiming at the Relay UE according to the residual energy of the source Relay UE.

In specific implementation, the base station determines whether to perform Relay UE reselection for the Remote UE by using two parameters, namely, the residual energy of the active Relay UE and the residual energy threshold of the source Relay UE, and the base station already configures the residual energy threshold of the active Relay UE, so that the base station needs to determine the residual energy of the source Relay UE before determining whether to perform Relay UE reselection for the Remote UE.

In specific implementation, the base station determines the residual energy of source Relay UE connected with the Relay UE by receiving the residual energy sent by the source Relay UE, and then determines whether to reselect the Relay UE for the Relay UE according to comparison between the residual energy and an existing residual energy threshold.

In implementation, the base station judges whether the residual energy is greater than a residual energy threshold value, and if so, connects to the source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, when the base station judges whether Relay UE is reselected for the Relay UE, if the base station judges that the residual energy is greater than the residual energy threshold, the base station determines that the residual energy of the source Relay UE is sufficient, and can stably provide service for the Relay UE, and the Relay UE is connected with the source Relay UE; otherwise, determining that the residual energy of the currently connected source Relay UE is too low to provide service for the Relay UE well, so that the Relay UE is reselected for the Relay UE. In the embodiment of the invention, when the residual energy of the source Relay UE is too low, the Relay UE is triggered to be reselected aiming at the Relay UE, so that the Relay UE can be connected with the reselected Relay UE in time, and the interruption of data transmission between the Relay UE and a base station caused by the energy exhaustion of the source Relay UE is avoided. The communication capability of Remote UE is improved, and the system performance is improved.

For example:

1. the residual energy threshold of source Relay UE of the Relay UE determined by the base station is 50% of electric quantity, and when the Relay UE determines that the residual energy of the source Relay UE is 35% of electric quantity, the Relay UE judges that the Relay UE reselects for the Relay UE because the residual energy of the source Relay UE is smaller than the residual energy threshold.

And 2, judging whether to reselect the Relay UE aiming at the Relay UE by the base station according to the load of the source Relay UE.

In specific implementation, the base station determines whether to perform Relay UE reselection for the Remote UE by using two parameters, namely, a load of the active Relay UE and a load threshold of the active Relay UE, and the base station has configured the load threshold of the active Relay UE, so that the base station needs to determine the load of the active Relay UE before determining whether to perform Relay UE reselection for the Remote UE.

In specific implementation, the base station determines the load of source Relay UE connected to the Relay UE by receiving the load sent by the source Relay UE, and then determines whether to reselect the Relay UE for the Relay UE by comparing the load of the source Relay UE with an existing load threshold.

In implementation, the base station judges whether the load of the source Relay UE is greater than a residual energy threshold value, and if so, maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, when the base station judges whether Relay UE is reselected for the Relay UE, if the base station judges that the load of the source Relay UE is smaller than a set load threshold, the base station determines that the residual energy of the source Relay UE is sufficient and can stably provide service for the Relay UE, and the Relay UE is connected with the source Relay UE; otherwise, determining that the residual energy of the currently connected source Relay UE is too low to provide service for the Relay UE well, and reselecting the Relay UE for the Relay UE. In the embodiment of the invention, when the residual energy of the source Relay UE is too low, the Relay UE is triggered to reselect the Relay UE, so that the Relay UE can be connected with the reselected Relay UE in time, and the interruption of data transmission between the Relay UE and the base station due to the energy exhaustion of the source Relay UE is avoided. The communication capability of Remote UE is improved, and the system performance is improved.

And 3, judging whether to reselect the Relay UE by the base station according to the quality of the Ullink channel between the source Relay UE and the base station.

In specific implementation, the base station determines whether to perform Relay UE reselection for the Remote UE by using two parameters, namely, the Uulink channel quality between the active Relay UE and the base station and the Uulink channel quality threshold between the active Relay UE and the base station, and the base station is configured with the Uulink channel quality threshold between the active Relay UE and the base station, so that before determining whether to perform Relay UE reselection for the Remote UE, the base station further needs to determine the Uulink channel quality between the active Relay UE and the base station.

In specific implementation, the base station determines the quality of the uuink channel between the source Relay UE and the base station by receiving the quality of the uuink channel between the source Relay UE and the base station, which is sent by the source Relay UE, and then determines whether to reselect the Relay UE for the Remote UE by comparing the quality of the uuink channel between the source Relay UE and the base station with an existing threshold value of the quality of the uuink channel between the source Relay UE and the base station.

The quality of the Uulink channel between the source Relay UE and the base station may also be directly obtained by the base station.

After determining the quality of the Ulink channel between the source Relay UE and the base station, the base station judges according to the quality of the Ulink channel between the source Relay UE and the base station and the existing threshold value of the Ulink channel quality, and determines whether to reselect Relay UE for RemoteUE.

In specific implementation, the base station judges whether the quality of a Uulink channel between source Relay UE connected with the Remote UE and the base station is greater than a set Uulink channel quality threshold, if so, the current connected source Relay UE is maintained; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, when the base station judges whether to reselect the Relay UE for the Relay UE, if the base station judges that the quality of the Uulink channel between the source Relay UE and the base station is greater than the set Uulink channel quality threshold, the channel quality between the source Relay UE and the base station is determined to be good, data transmission can be stably carried out, and the Relay UE maintains the currently connected source Relay UE; otherwise, it is determined that the Uulink channel quality between the currently connected source Relay UE and the base station is poor and data transmission is not possible, that is, the source Relay UE cannot maintain Relay capability, so that the Relay UE is reselected for the Remote UE. Therefore, when the quality of the Ulink channel between the source Relay UE and the base station is poor and the Relay capability cannot be maintained, the base station can select the new Relay UE of the Remote UE and indicate the Remote UE to access, and the interruption of data transmission between the Remote UE and the base station due to the fact that the quality of the Ulink channel between the source Relay UE and the base station cannot realize data transmission is avoided.

And 4, judging whether to reselect the Relay UE according to the residual energy of the source Relay UE and the sidelink channel quality between the Relay UE and the source Relay UE by the base station in a triggering mode 4.

In specific implementation, the base station determines whether to perform reselection of Relay UE for the Relay UE by using parameters including residual energy of active Relay UE, sidelink channel quality between the Relay UE and the source Relay UE, a residual energy threshold of the source Relay UE, and a sidelink channel quality threshold between the Relay UE and the source Relay UE, and the base station has configured therein the residual energy threshold of the active Relay UE and the sidelink channel quality threshold between the Relay UE and the source Relay UE, so that the base station needs to determine the residual energy of the source Relay UE and the sidelink channel quality between the Relay UE and the source Relay UE before determining whether to perform reselection of the Relay UE for the Relay UE.

In specific implementation, the base station directly receives the residual energy of the source Relay UE and the sidelink channel quality between the Relay UE and the source Relay UE, which are sent by the source Relay UE, and then determines whether to reselect the Relay UE for the Relay UE by comparing the received residual energy of the source Relay UE, the sidelink channel quality between the Relay UE and the source Relay UE, the existing residual energy threshold of the source Relay UE, and the sidelink channel quality threshold between the Relay UE and the source Relay UE.

After determining the residual energy of source Relay UE and the sidelink channel quality between Remote UE and the source Relay UE, the base station judges according to the received residual energy of the source Relay UE, the sidelink channel quality between the Remote UE and the source Relay UE, the residual energy threshold of the existing source Relay UE and the sidelink channel quality threshold between the existing Remote UE and the source Relay UE, and determines whether to reselect the Relay UE for the Relay UE.

In implementation, the base station determines whether the residual energy of the source Relay UE is greater than a set residual energy threshold, and whether the sidelink channel quality between the Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold, and if so, maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, the currently connected source Relay UE is maintained only when the residual energy of the source Relay UE connected with the Remote UE and the sidelink channel quality between the Remote UE and the source Relay UE are both greater than the set threshold; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, when the residual energy of the source Relay UE is too low or the quality of a sidelink channel between the Relay UE and the source Relay UE is too low, the base station selects a new Relay UE and accesses the Relay UE, thereby avoiding the possibility of data transmission interruption between the Relay UE and the base station due to the fact that the source Relay UE cannot maintain the Relay capability, improving the communication capability of the Relay UE, and improving the system performance.

For example:

If the residual energy of the source Relay UE currently connected by the Relay UE is 35% of electric quantity, and the sidelink channel quality between the Relay UE and the source Relay UE currently connected by the Relay UE is 22, the Relay UE is reselected for the Relay UE because the residual energy of the source Relay UE is less than a residual energy threshold and the sidelink channel quality between the Relay UE and the source Relay UE is less than a sidelink channel quality threshold.

And a triggering mode 5, judging whether to reselect the Relay UE according to the load of the source Relay UE and the sidelink channel quality between the Relay UE and the source Relay UE by the base station.

In specific implementation, the base station determines whether to perform reselection of Relay UE for the Relay UE by using parameters including a load of an active Relay UE, a sidelink channel quality between the Relay UE and the source Relay UE, a load threshold of the source Relay UE, and a sidelink channel quality threshold between the Relay UE and the source Relay UE, and the base station has configured therein the load threshold of the active Relay UE and the sidelink channel quality threshold between the Relay UE and the source Relay UE, so that before determining whether to perform reselection of the Relay UE for the Relay UE, the base station needs to determine the load of the source Relay UE and the sidelink channel quality between the Relay UE and the source Relay UE.

The manner in which the base station determines the load of the source Relay UE and the sidelink channel quality between the Relay UE and the source Relay UE in the triggering manner 5 is similar to the manner in which the base station determines whether to perform reselection triggering of the Relay UE for the Relay UE by one to four times, and therefore, description is omitted.

After determining the load of source Relay UE and the sidelink channel quality between Remote UE and the source Relay UE, the base station judges according to the received load of the source Relay UE, the sidelink channel quality between the Remote UE and the source Relay UE, the load threshold of the existing source Relay UE and the sidelink channel quality threshold between the existing Remote UE and the source Relay UE, and determines whether to reselect the Relay UE for the Relay UE.

In specific implementation, the base station determines whether the load of the source Relay UE is smaller than a set load threshold, and whether the sidelink channel quality is greater than a set sidelink channel quality threshold, and if so, maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, only when the load of the source Relay UE is smaller than a set load threshold value and the sidelink channel quality is larger than a set sidelink channel quality threshold value, the source Relay UE can maintain the Relay capability, and the Remote UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. This may make the communication between the Remote UE and the currently connected Relay UE more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

If the load of the source Relay UE is determined to be 3 UEs and the sidelink channel quality between the Relay UE and the source Relay UE is determined to be 26, the load of the source Relay UE is smaller than the load threshold value and the sidelink channel quality between the Relay UE and the source Relay UE is larger than the sidelink channel quality threshold value, so that the source Relay UE currently connected is maintained.

And 6, judging whether to reselect the Relay UE by the base station according to the quality of the Ullink channel between the source Relay UE and the base station and the quality of the sidelink channel between the Relay UE and the source Relay UE.

In specific implementation, the base station determines whether to perform reselection of the Relay UE for the Relay UE by using parameters including a Uulink channel quality between the active Relay UE and the base station, a sidelink channel quality between the Relay UE and the source Relay UE, a Uulink channel quality threshold between the source Relay UE and the base station, and a sidelink channel quality threshold between the Relay UE and the source Relay UE, where the base station has been configured with the Uulink channel quality threshold between the active Relay UE and the base station and the sidelink channel quality threshold between the Relay UE and the source Relay UE, so that before determining whether to perform reselection of the Relay UE for the Relay UE, the base station further needs to determine the Uulink channel quality between the source Relay UE and the base station and the sidelink channel quality between the Relay UE and the source Relay UE.

The manner in which the base station determines the uuink channel quality between the source Relay UE and the base station and the sidelink channel quality between the Remote UE and the source Relay UE in the triggering manner 6 is similar to the first to fourth manners in which the base station determines whether to perform reselection triggering of the Relay UE for the Remote UE, and therefore, description is omitted.

After determining the quality of a Uulink channel between source Relay UE and a base station and the quality of a sidelink channel between Remote UE and the source Relay UE, the base station judges according to the received quality of the Uulink channel between the source Relay UE and the base station, the quality of the sidelink channel between the Remote UE and the source Relay UE, the quality threshold of the Uulink channel between the existing source Relay UE and the base station and the quality threshold of the sidelink channel between the existing Remote UE and the source Relay UE, and determines whether to reselect the Relay UE for the Relay UE.

In specific implementation, the base station determines whether the quality of a Uulink channel between source Relay UE and the base station and the Remote UE are greater than a set Uulink channel quality threshold, and whether the quality of a sidelink channel between the Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold between the source Relay UEs, if so, the currently connected source Relay UE is maintained; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, only when the quality of a Uulink channel between source Relay UE and a base station is greater than a set Uulink channel quality threshold and the quality of a sidelink channel between Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold, the source Relay UE is determined to be capable of maintaining the Relay capability, and the Remote UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. This may make the communication between the Remote UE and the currently connected Relay UE more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

And a triggering mode 7, judging whether to reselect the Relay UE aiming at the Relay UE by the base station according to the residual energy of the Source Relay UE and the load of the Source Relay UE.

In specific implementation, the base station determines whether to perform reselection of the Relay UE for the Remote UE by using parameters of the residual energy of the active Relay UE, the load of the source Relay UE, the residual energy threshold of the source Relay UE, and the load threshold of the source Relay UE, and the base station has configured the residual energy threshold of the active Relay UE and the load threshold of the source Relay UE, so that before determining whether to perform reselection of the Relay UE for the Remote UE, the base station further needs to determine the residual energy of the source Relay UE and the load of the source Relay UE.

The manner in which the base station determines the residual energy of the source Relay UE and the load of the source Relay UE in the trigger manner 7 is similar to the first to fourth manners in which the base station determines whether to perform reselection trigger of the Relay UE for the Remote UE, and therefore details are not repeated.

After determining the residual energy of the source Relay UE and the load of the source Relay UE, the base station determines whether to reselect the Relay UE for the Remote UE according to the received residual energy of the source Relay UE, the received load of the source Relay UE, the existing residual energy threshold of the source Relay UE and the existing load threshold of the source Relay UE.

In specific implementation, the base station determines whether the residual energy of the source Relay UE is greater than a set source residual energy threshold and whether the load of the source Relay UE is less than a set load threshold, and if so, maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, only when the residual energy of the source Relay UE is greater than the set source residual energy threshold and the load of the source Relay UE is less than the set load threshold, the source Relay UE is determined to be capable of maintaining the Relay capability, and the Remote UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, the RemoteUE can trigger and reselect the Relay UE in time under the condition that the residual energy of the source Relay UE is too low or the source Relay UE is overloaded, and the communication between the Remote UE and the Relay UE can be more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

And the triggering mode 8 is that the base station judges whether to reselect the Relay UE according to the residual energy of the Source Relay UE and the Uulink channel quality between the Source Relay UE and the base station.

In specific implementation, the base station determines whether to reselect the Relay UE for the Relay UE needs parameters such as a residual energy of the active Relay UE, a uuink channel quality between the active Relay UE and the base station, a residual energy threshold of the active Relay UE, and a uuink channel quality threshold between the active Relay UE and the base station, and the base station has been configured with the residual energy threshold of the active Relay UE and the uuink channel quality threshold between the active Relay UE and the base station.

The manner in which the base station determines the residual energy of the source Relay UE and the uuink channel quality between the source Relay UE and the base station in the trigger manner 8 is similar to the first to fourth manners in which the base station determines whether to perform reselection trigger of the Relay UE for the Remote UE, and therefore, description is omitted.

After determining the residual energy of the source Relay UE and the Ulink channel quality between the source Relay UE and the base station, the base station judges according to the received residual energy of the source Relay UE, the Ulink channel quality between the source Relay UE and the base station, the existing residual energy threshold of the source Relay UE and the existing Ulink channel quality threshold between the source Relay UE and the base station, and determines whether to reselect the Relay UE for the Remote UE.

In specific implementation, the base station judges whether the residual energy of the source Relay UE is greater than a set source residual energy threshold value or not, and whether the quality of a Uulink channel between the source Relay UE and the base station is greater than a set Uulink channel quality threshold value or not, and if so, the currently connected source Relay UE is maintained; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, only when the residual energy of the source Relay UE is greater than the set source residual energy threshold and the Uulink channel quality between the source Relay UE and the base station is greater than the set Uulink channel quality threshold, the source Relay UE is determined to be capable of maintaining the Relay capability, and the Remote UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, the Relay UE can be triggered and reselected in time under the condition that the residual energy of the source Relay UE is too low or mutual data transmission cannot be carried out between the source Relay UE and the base station, and the communication between the Relay UE and the Relay UE can be more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

And 9, the base station judges whether to reselect the Relay UE aiming at the Remote UE according to the load of the source Relay UE and the quality of the Ullink channel between the source Relay UE and the base station.

In specific implementation, the base station determines whether to perform reselection of the Relay UE for the Relay UE by using parameters such as a load of the active Relay UE, a quality of an Uulink channel between the active Relay UE and the base station, a load threshold of the active Relay UE, and a quality threshold of the Uulink channel between the active Relay UE and the base station, and the base station is configured with the load threshold of the active Relay UE and the quality threshold of the Uulink channel between the active Relay UE and the base station.

The manner in which the base station determines the load of the source Relay UE and the uuink channel quality between the source Relay UE and the base station in the trigger manner 9 is similar to the first to fourth manners in which the base station determines whether to perform reselection trigger of the Relay UE for the Remote UE, and therefore, description is omitted.

After determining the load of the source Relay UE and the quality of the Ulink channel between the source Relay UE and the base station, the base station judges according to the received load of the source Relay UE, the quality of the Ulink channel between the source Relay UE and the base station, the load threshold of the existing source Relay UE and the quality threshold of the Ulink channel between the existing source Relay UE and the base station, and determines whether to reselect the Relay UE for the Remote UE.

In specific implementation, the base station determines whether the load of the source Relay UE is smaller than a set load threshold, and whether the quality of a Uulink channel between the source Relay UE and the base station is greater than the set Uulink channel quality threshold, if so, the currently connected source Relay UE is maintained; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, only when the load of the source Relay UE is smaller than a set load threshold value and the Uulink channel quality between the source Relay UE and the base station is larger than a set Uulink channel quality threshold value, the source Relay UE is determined to be capable of maintaining the Relay capability, and the Remote UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, the Relay UE can be triggered and reselected in time under the condition that the source Relay UE is overloaded or data transmission cannot be carried out between the source Relay UE and the base station, and the communication between the Relay UE and the Relay UE can be more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

And the triggering mode 10 is that the base station judges whether to reselect the Relay UE according to the residual energy of the Source Relay UE, the load of the Source Relay UE and the sidelink channel quality between the Relay UE and the Source Relay UE.

In a specific implementation, the base station determines whether to perform reselection of the Relay UE for the Relay UE by using parameters of a residual energy of the active Relay UE, a load of the active Relay UE, a sidelink channel quality between the Relay UE and the source Relay UE, a residual energy threshold of the source Relay UE, a load threshold of the source Relay UE, and a sidelink channel quality threshold between the Relay UE and the source Relay UE, and the base station has configured therein the residual energy threshold of the active Relay UE, the load threshold of the source Relay UE, and the sidelink channel quality threshold between the Relay UE and the source Relay UE, so that before determining whether to perform reselection of the Relay UE for the Relay UE, the base station needs to determine the residual energy of the source Relay UE, the load of the source Relay UE, and the sidelink channel quality between the Relay UE and the source Relay UE.

The manner in which the base station determines the residual energy of the source Relay UE, the load of the source Relay UE, and the sidelink channel quality between the Relay UE and the source Relay UE in the triggering manner 10 is similar to the first to fourth manners in which the base station determines whether to perform reselection triggering of the Relay UE for the Relay UE, and thus, description is omitted.

After determining the residual energy of the source Relay UE, the load of the source Relay UE and the Uulink channel quality between the source Relay UE and the base station, the base station judges according to the received residual energy of the source Relay UE, the load of the source Relay UE, the sidelink channel quality between the Remote UE and the source Relay UE, the existing residual energy of the source Relay UE, the existing load threshold of the source Relay UE and the Uulink channel quality threshold between the existing source Relay UE and the base station, and determines whether to reselect the Relay UE for the Remote UE.

In specific implementation, the base station determines whether the residual energy of the source Relay UE is greater than a set source residual energy threshold, whether the load of the source Relay UE is less than a set load threshold, and whether the quality of a sidelink channel between the Relay UE and the source Relay UE is greater than a set sidelink channel quality threshold, and if so, maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, only when the residual energy of the source Relay UE is greater than a set source residual energy threshold, the load of the source Relay UE is less than a set load threshold, and the quality of a sidelink channel between the Relay UE and the source Relay UE is greater than a set sidelink channel quality threshold, it is determined that the source Relay UE can maintain the Relay capability, and the Relay UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, when the residual energy of the source Relay UE is too low, or the source Relay UE is overloaded, or the sidelink channel quality between the Relay UE and the source Relay UE is poor, the Relay UE is triggered to reselect in time, so that the communication between the Relay UE and the Relay UE is more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

In specific implementation, the base station determines whether to perform reselection of Relay UE for the Relay UE by using parameters such as residual energy of active Relay UE, Uulink channel quality between the source Relay UE and the base station, sidelink channel quality between the Relay UE and the source Relay UE, residual energy threshold of the source Relay UE, Uulink channel quality threshold between the source Relay UE and the base station, and sidelink channel quality threshold between the Relay UE and the source Relay UE, the base station is configured with a residual energy threshold of the source Relay UE, a Uulink channel quality threshold between the source Relay UE and the base station and a sidelink channel quality threshold between the Remote UE and the source Relay UE, thus, before determining whether to perform reselection of Relay UE for the Relay UE, the base station further needs to determine the residual energy of the source Relay UE, the Uulink channel quality between the source Relay UE and the base station, and the sidelink channel quality between the Relay UE and the source Relay UE.

The manner in which the base station determines the residual energy of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, and the sidelink channel quality between the Remote UE and the source Relay UE in the triggering manner 11 is similar to the manner in which the base station determines whether to perform reselection triggering of the Relay UE for the Remote UE by one to four, and therefore, description is omitted.

In specific implementation, the base station determines whether the residual energy of the source Relay UE is greater than a set source residual energy threshold, whether the Uulink channel quality between the source Relay UE and the base station is greater than a set Uulink channel quality threshold, and whether the sidelink channel quality between the Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold between the source Relay UEs, and if so, maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, only when the residual energy of the source Relay UE is greater than a set source residual energy threshold, the quality of a Uulink channel between the source Relay UE and the base station is greater than a set Uulink channel quality threshold, and whether the quality of a sidelink channel between the Relay UE and the source Relay UE is greater than a set sidelink channel quality threshold between the Source Relay UE or not, it is determined that the source Relay UE can maintain the Relay capability, and the Relay UE maintains the currently connected Source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, the Relay UE is triggered to reselect under the condition that the residual energy of the Relay UE is too low, or the mutual data transmission between the source Relay UE and the base station cannot be carried out, or the data transmission between the Relay UE and the source Relay UE cannot be carried out, so that the communication between the Relay UE and the Relay UE is more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

In a specific implementation, the base station determines whether to perform reselection of the Relay UE for the Relay UE by using parameters including a load of the active Relay UE, a uuink channel quality between the active Relay UE and the base station, a sidelink channel quality between the Relay UE and the active Relay UE, a load threshold of the active Relay UE, a uuink channel quality threshold between the active Relay UE and the base station, and a sidelink channel quality threshold between the Relay UE and the active Relay UE, where the base station has been configured with the load threshold of the active Relay UE, the uuink channel quality threshold between the active Relay UE and the base station, and the sidelink channel quality threshold between the Relay UE and the active Relay UE, so that before determining whether to perform reselection of the Relay UE for the Relay UE, the base station needs to determine the load of the active Relay UE, the uuink channel quality between the active Relay UE and the base station, and the sidelink channel quality between the Relay UE and the active Relay UE.

The manner in which the base station determines the load of the source Relay UE, the uuink channel quality between the source Relay UE and the base station, and the sidelink channel quality between the Remote UE and the source Relay UE in the triggering manner 11 is similar to the first to fourth manners in which the base station determines whether to perform reselection triggering of the Relay UE for the Remote UE, and therefore, description is omitted.

After determining the load of the source Relay UE, the load of the source Relay UE and the quality of the Ulink channel between the source Relay UE and the base station, the base station determines whether to reselect the Relay UE for the Relay UE according to the received load of the source Relay UE, the quality of the silink channel between the RemoteUE and the source Relay UE, the load of the existing source Relay UE, the load threshold of the existing source Relay UE and the quality threshold of the Ulink channel between the existing source Relay UE and the base station.

In specific implementation, the base station determines whether the load of the source Relay UE is less than a set load threshold, whether the Uulink channel quality between the source Relay UE and the base station is greater than a set Uulink channel quality threshold, and whether the sidelink channel quality between the Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold between the source Relay UEs, if so, the currently connected source Relay UE is maintained; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, only when the load of the source Relay UE is smaller than a set load threshold, the quality of a Uulink channel between the source Relay UE and the base station is greater than a set Uulink channel quality threshold, and the quality of a sidelink channel between the RemoteUE and the source Relay UE is greater than a set sidelink channel quality threshold, it is determined that the source Relay UE can maintain the Relay capability, and the Remote UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, the Relay UE can be triggered and reselected in time under the condition that the source Relay UE is overloaded, or data transmission cannot be carried out between the source Relay UE and the base station, or data transmission cannot be carried out between the Relay UE and the source Relay UE, so that the communication between the Relay UE and the Relay UE is more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

In specific implementation, the base station determines whether to perform reselection of the Relay UE on the Relay UE by using parameters such as a residual energy of the active Relay UE, a load of the active Relay UE, a uuink channel quality between the active Relay UE and the base station, a residual energy threshold of the active Relay UE, a load threshold of the active Relay UE, and a uuink channel quality threshold between the active Relay UE and the base station, where the residual energy threshold of the active Relay UE, the load threshold of the active Relay UE, and the uuink channel quality threshold between the active Relay UE and the base station have been configured in the base station, so that before determining whether to perform reselection of the Relay UE on the Relay UE, the base station further needs to determine the residual energy of the active Relay UE, the load of the active Relay UE, and the uuink channel quality between the active Relay UE and the base station.

The manner in which the base station determines the residual energy of the source Relay UE, the load of the source Relay UE, and the uuink channel quality between the source Relay UE and the base station in the trigger manner 13 is similar to the first to fourth manners in which the base station determines whether to perform reselection trigger of the Relay UE for the Remote UE, and therefore details are not repeated.

After determining the residual energy of the source Relay UE, the load of the source Relay UE and the quality of the Ulink channel between the source Relay UE and the base station, the base station determines whether to reselect the Relay UE for the Relay UE according to the received residual energy of the source Relay UE, the load of the source Relay UE, the quality of the Ulink channel between the source Relay UE and the base station, the load of the existing source Relay UE, the load threshold of the existing source Relay UE and the quality threshold of the Ulink channel between the existing source Relay UE and the base station.

In specific implementation, the base station determines whether the residual energy of the source Relay UE is greater than a set source residual energy threshold, whether the load of the source Relay UE is less than a set load threshold, and whether the quality of the uuink channel between the source Relay UE and the base station is greater than a set uuink channel quality threshold, if so, the currently connected source Relay UE is maintained; otherwise, the Relay UE is reselected aiming at the Remote UE.

In a specific implementation, the base station determines whether to perform reselection of the Relay UE for the Relay UE needs to determine the residual energy of the active Relay UE, the load of the active Relay UE, the Uulink channel quality between the active Relay UE and the base station, the sidelink channel quality between the Relay UE and the active Relay UE, the residual energy threshold of the active Relay UE, the load threshold of the active Relay UE, the Uulink channel quality threshold between the active Relay UE and the base station, and the sidelink channel quality threshold between the Relay UE and the active Relay UE, where the residual energy threshold of the active Relay UE, the load threshold of the active Relay UE, the Uulink channel quality threshold between the active Relay UE and the base station, and the sidelink channel quality threshold between the Relay UE and the active Relay UE have been configured in the base station, and thus before determining whether to perform reselection of the Relay UE for the Relay UE, the residual energy of the base station needs to determine the residual energy, the load threshold of the active Relay UE, the residual energy of the Relay UE, the load threshold of the Relay UE, Uuink channel quality between source Relay UE and base station, and sidelink channel quality between Remote UE and source Relay UE.

The manner in which the base station determines the residual energy of the source Relay UE, the load of the source Relay UE, the Uulink channel quality between the source Relay UE and the base station, and the sidelilink channel quality between the Relay UE and the source Relay UE in the triggering manner 13 is similar to the manner in which the base station determines whether to perform reselection triggering of the Relay UE for the Relay UE, i.e., one to four, and therefore, description is omitted.

After determining the residual energy of the source Relay UE, the load of the source Relay UE, the Uulink channel quality between the source Relay UE and the base station, and the sidelink channel quality between the Remote UE and the source Relay UE, the base station judges according to the received residual energy of the source Relay UE, the load of the source Relay UE, the Uulink channel quality between the source Relay UE and the base station, the sidelink channel quality between the Remote UE and the source Relay UE, the load of the existing source Relay UE, the load threshold of the existing source Relay UE, the Uulink channel quality threshold between the existing source Relay UE and the base station, the residual energy of the existing source Relay UE, the load of the source Relay UE, the Uulink channel quality between the source Relay UE and the base station, and the sidelink channel quality between the Remote UE and the source Relay UE, and determines whether to reselect the Relay UE for the Remote UE.

In specific implementation, the base station determines whether the residual energy of the source Relay UE is greater than a set source residual energy threshold, and whether the load of the source Relay UE is less than a set load threshold, and whether the quality of the Uulink channel between the source Relay UE and the base station is greater than a set Uulink channel quality threshold, and the quality of the sidelink channel between the Remote UE and the source Relay UE is greater than a set sidelink channel quality threshold, and if so, maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE.

In the method, only when the residual energy of the source Relay UE is greater than a set source residual energy threshold, the load of the source Relay UE is less than a set load threshold, the quality of a Uulink channel between the source Relay UE and the base station is greater than a set Uulink channel quality threshold, and the quality of a sidelink channel between the Relay UE and the source Relay UE is greater than a set sidelink channel quality threshold, it is determined that the source Relay UE can maintain the Relay capability, and the Relay UE maintains the currently connected source Relay UE; otherwise, the Relay UE is reselected aiming at the Remote UE. Therefore, the Relay UE is triggered to reselect under the condition that the residual energy of the Relay UE is too low, or the source Relay UE is overloaded, or data transmission cannot be performed between the source Relay UE and the base station, or data transmission cannot be performed between the Relay UE and the source Relay UE, so that the communication between the Relay UE and the Relay UE is more stable. Therefore, the communication capability of the Remote UE is improved, and the system performance is improved.

And the Remote UE judges whether to reselect Relay UE aiming at the Remote UE according to the reselection information, and if the Relay UE is determined to need to be reselected aiming at the Remote UE, the Remote UE further reselects a UE as a target Relay UE of the Remote UE.

And if the base station selects and determines the target Relay UE according to the information for selecting the target Relay UE.

Optionally, if it is determined that Relay UE needs to be reselected for the Relay UE, the Relay UE determines information for selecting target Relay UE according to measurement parameters configured by the base station, reports the information for selecting target Relay UE to the base station, and the base station selects the target Relay UE.

When the sidelink between the Remote UE and the Relay UE is of a bidirectional type, all the parameters can be directly measured and acquired by the Remote UE and then uploaded to the base station; the Remote UE can also measure and acquire the id of the adjacent cell base station and the quality of the Ullink between the Remote UE and the adjacent cell base station, and then the acquired parameter information is uploaded to the base station, the relevant parameters of the candidate Relay UE are acquired by each candidate Relay UE and the id of the candidate Relay UE, the quality of the Sidelink link between the candidate Relay UE and the user plane of the Remote UE, the id of the cell to which the candidate Relay UE belongs, the quality of the Ullink between the candidate Relay UE and the base station, the residual electric quantity of the Relay UE, the load of the Relay UE and other parameter information are reported to the base station;

when the sidelink between the Remote UE and the Relay UE is of a unidirectional type, the Remote UE cannot directly receive the message sent by the Relay UE at this time and cannot directly measure and acquire the relevant measurement parameters of the candidate Relay UE, so all the parameters can only be measured and acquired by the Remote UE to acquire the id of the base station of the adjacent cell and the link quality of the Ullink between the Remote UE and the base station of the adjacent cell and report the link quality to the base station; and then the candidate Relay UE acquires and reports the id of the Relay UE, the quality of the Sidelink link between the Relay UE and the user plane of the Relay UE, the id of the cell to which the Relay UE belongs, the quality of the Ulink link between the Relay UE and the base station, the residual electric quantity of the Relay UE and the load of the Relay UE to the base station, and the Relay UE forwards the residual electric quantity of the Relay UE and the load of the Relay UE to the Relay UE.

After the Relay UE is selected for the Relay UE, the Relay UE determines that no available Relay UE exists, and selects an available base station according to the id of the adjacent cell base station measured by the Relay UE and the link quality of the adjacent cell base station Uulink, and accesses the base station to perform data transmission.

When the base station determines the target Relay UE, the Remote UE needs to determine information for selecting the target Relay UE according to the measurement parameters configured by the base station, and the base station selects and determines the target Relay UE according to the information for selecting the target Relay UE, which is similar to the method for selecting and determining the target Relay UE by the Remote UE according to the information for selecting the target Relay UE, and reference may be made to the description of the Remote UE selecting and determining the target Relay UE according to the information for selecting the target Relay UE, so that details are not repeated herein.

Embodiments of the present invention will be described below with respect to timing diagrams.

A flowchart of a method for reselecting a Relay UE according to an embodiment of the present invention is shown in fig. 11.

Step 1100, data is sent and received between the Remote UE and the eNB through Relay UE 1;

1101, measuring performance information of Relay UE1 by Relay UE 1;

step 1102, the Relay UE1 sending the measured performance information of the Relay UE1 to the eNB;

step 1103, the eNB determines whether to perform Relay UE reselection for the Remote UE according to the reselection information;

step 1104, the eNB sends a Relay reselection notification to the Remote UE;

step 1105, the Remote UE measures to obtain information for selecting target Relay UE;

step 1106, the Remote UE uploads the measured information for selecting the target Relay UE to the eNB;

step 1107, the eNB selects a target Relay UE according to the information uploaded by the Remote UE for selecting the target Relay UE;

step 1108, the eNB sends a Relay reselection request to Relay UE2, where the request message carries information of the Remote UE;

step 1109, Relay UE2 sends a Relay reselection acknowledgement message to eNB;

step 1110, the eNB sends a Relay reselection acknowledgement message to the Remote UE;

step 1111, establishing a PC5 connection between the Remote UE and the Relay UE 2;

step 1112, establishing RRC connection between the Relay UE2 and the eNB;

step 1113, disconnecting the PC5 between the Remote UE and the Relay UE 1;

step 1114, the eNB performs RRC sidelink reconfiguration for the Remote UE via Relay UE 2;

and step 1115, transmitting and receiving data between the Remote UE and the eNB through the Relay UE 2.

In a second scenario, as shown in fig. 4, the source Relay UE and the target Relay UE belong to different enbs, and the Remote UE only has the capability of sending a sidelink, that is, the RRC sidelink between the Remote UE and the Relay UE is of a unidirectional transmission type. The Relay UE1 is used as a source Relay UE connected with the Remote UE, and the eNB1 is a serving base station of the source Relay UE; the Relay UE2 is a target Relay UE reselected by the Remote UE, and the eNB2 is a serving base station of the target Relay UE.

A flowchart of a method for reselecting a Relay UE according to an embodiment of the present invention is shown in fig. 12.

Step 1200, data is transmitted and received between the Remote UE and the eNB1 through the Relay UE 1;

step 1201, the Relay UE1 measures the performance information of the Relay UE 1;

step 1202, the Relay UE1 sends the measured performance information of the Relay UE1 to the eNB 1;

step 1203, the eNB1 determines whether to perform Relay UE reselection for the Remote UE according to the reselection information;

step 1204, eNB1 sends a Relay reselection notification to the Remote UE;

step 1205, Remote UE measures to obtain information for selecting target Relay UE;

step 1206, the Remote UE sends information for selecting a target Relay UE to the eNB 1;

step 1207, the eNB1 selects a target Relay UE2 according to the information uploaded by the Remote UE and used for selecting the target Relay UE;

step 1208, the Remote UE sends a Relay reselection request to the eNB1, and the Relay reselection request is forwarded to the eNB2 by the eNB1, where the request message carries information of the Remote UE;

step 1209, the eNB2 sends a Relay reselection request to the Relay UE2, where the request message carries Remote UE information;

step 1210, the Relay UE2 sends a Relay reselection confirm message to the eNB 2;

step 1211, the eNB2 sends a Relay reselection confirm message to the Remote UE;

step 1212, establishing a PC5 connection between the Remote UE and the Relay UE 2;

step 1213, establishing RRC connection between Relay UE2 and eNB 2;

step 1214, disconnecting the PC5 connection between the Remote UE and the Relay UE 1;

step 1215, the eNB2 station performs RRC sidelink reconfiguration for the Remote UE via Relay UE 2;

in step 1216, the Remote UE and the eNB2 transmit and receive data via the Relay UE 2.

In a third scenario, as shown in fig. 6, the source Relay UE and the target Relay UE belong to different enbs, and the Remote UE has the capability of receiving and transmitting in sidelink at the same time, that is, the RRC sidelink between the Remote UE and the Relay UE is a bidirectional transmission type. The Relay UE1 serves as a source Relay UE to which the Relay UE is connected, and the eNB1 serves as a serving base station of the source Relay UE 1; the Relay UE2 is the target Relay UE reselected by the Remote UE, and the eNB2 is the serving base station of the target Relay UE 2.

A flowchart of a method for reselecting a Relay UE according to an embodiment of the present invention is shown in fig. 13.

Step 1300, data is sent between the Remote UE and the eNB through Relay UE 1;

step 1301, Relay UE1 measures performance information of Relay UE 1;

step 1302, the Relay UE1 sending the measured performance information of the Relay UE1 to the eNB;

step 1303, the eNB judges and determines whether to perform Relay UE reselection for the Remote UE according to the reselection information;

step 1304, the eNB sends a Relay reselection notification to the Remote UE;

step 1305, Remote UE measures to obtain information for selecting target Relay UE;

step 1306, the Remote UE uploads the measured information for selecting the target Relay UE to the eNB;

step 1307, the eNB selects a target Relay UE2 according to the information uploaded by the Remote UE for selecting the target Relay UE;

step 1308, the eNB sends a Relay reselection request to a Relay UE2, where the request message carries information of a Remote UE;

step 1309, Relay UE2 sends a Relay reselection confirm message to eNB;

step 1310, the eNB sends a Relay reselection confirmation message to the Remote UE;

step 1311, establishing a PC5 connection between the Remote UE and the Relay UE 2;

step 1312, establishing RRC connection between Relay UE2 and eNB;

step 1313, disconnecting the PC5 between the Remote UE and the Relay UE 1;

step 1314, the eNB performs RRC sidelink reconfiguration for the Remote UE via Relay UE 2;

step 1315, data is sent between the Remote UE and the eNB through the Relay UE 2.

A flowchart of a method for reselecting a Relay UE according to an embodiment of the present invention is shown in fig. 14.

Step 1400, data is transmitted between the Remote UE and the eNB1 through a Relay UE 1;

1401, the Relay UE1 measures the performance information of the Relay UE 1;

step 1402, the Relay UE1 sends the measured performance information of the Relay UE1 to the eNB 1;

step 1403, the eNB1 determines whether to perform Relay UE reselection for the Remote UE according to the reselection information;

step 1404, the eNB1 sends a Relay reselection notification to the Remote UE;

step 1405, the Remote UE measures to obtain information for selecting the target Relay UE;

step 1406, the Remote UE sends information for selecting a target Relay UE to the eNB 1;

step 1407, the eNB1 selects a target Relay UE2 according to the information uploaded by the Remote UE and used for selecting the target Relay UE;

step 1408, the Remote UE sends a Relay reselection request to the eNB1, and the request message is transferred to the eNB2 by the eNB1, where the request message carries information of the Remote UE;

step 1409, the eNB2 sends a Relay reselection request to the Relay UE2, where the request message carries the Remote UE information;

step 1410, the Relay UE2 sends a Relay reselection confirm message to the eNB 2;

step 1411, eNB2 sends a Relay reselection confirm message to the Remote UE;

step 1412, establishing a PC5 connection between the Remote UE and the Relay UE 2;

step 1413, establishing RRC connection between the Relay UE2 and the eNB 2;

step 1414, disconnecting the PC5 connection between the Remote UE and the Relay UE 1;

step 1415, the eNB2 station performs RRC sidelink reconfiguration for the Remote UE via Relay UE 2;

in step 1416, data is transmitted between the Remote UE and the eNB2 via the Relay UE 2.

In addition, when the Remote UE realizes data transmission between the Remote UE and the base station through the Remote UE, RRC Sidelink needs to be established between the Remote UE and the base station and between the Remote UE and the Remote UE, and the RRC Sidelink has two types, one is a bidirectional type and the other is a unidirectional type. When the base station judges whether to reselect the Relay UE aiming at the Remote UE, the type of the RRC sidelink has no influence on the operation steps of reselecting the Relay UE.

When a Remote UE currently performs data transmission through a base station, when the quality of a Uulink channel between the Remote UE and the base station is lower than a set threshold, communication cannot be maintained, and the Remote UE finds a Sidelink link meeting the link quality threshold, it will also trigger selection of a Relay UE for the Remote UE, so as to perform data transmission between the Relay UE and the base station.

Based on the same inventive concept, the embodiment of the present invention further provides a device for reselecting Relay UE, and as the Remote UE, the base station, and the UE in the device are the Remote UE and the base station in the embodiment of the present invention, and the principle of the device for solving the problem is similar to that of the method, the implementation of the device may refer to the implementation of the method, and repeated details are not repeated.

As shown in fig. 15, an embodiment of the present invention provides a Remote UE for reselecting a Relay UE, where the triggering device includes:

at least one processor 1500 and at least one memory 1501, wherein said memory stores program code that, when executed by said processor, causes said processor to perform the following:

when source Relay UE is connected with a base station, determining reselection information, and judging whether to reselect Relay UE for the Relay UE according to the reselection information, wherein the reselection information is the performance information of the source Relay UE, and the reselection information comprises the performance information of the source Relay UE and the first channel quality between the Relay UE and the source Relay UE; wherein the capability information of the source Relay UE includes part or all of the following: the remaining energy of the source Relay UE, the load of the source Relay UE, and a second channel quality between the source Relay UE and the base station.

Optionally, the processor 1500 is specifically configured to: determining performance information of the source Relay UE in the reselection information by:

and receiving the performance information sent by the source Relay UE or the base station.

Optionally, the processor 1500 is further configured to:

after judging whether Relay UE is reselected aiming at the Remote UE according to the reselection information, if the Relay UE is determined to be reselected aiming at the Remote UE, determining information for selecting target Relay UE according to measurement parameters configured by a base station, selecting the target Relay UE according to the information for selecting the target Relay UE, and informing the base station of the selected target Relay UE; or

If the Relay UE needs to be reselected aiming at the Remote UE, determining information for selecting the target Relay UE according to the measurement parameters configured by the base station, reporting the information for selecting the target Relay UE to the base station, and selecting the target Relay UE by the base station;

As shown in fig. 16, an embodiment of the present invention provides a base station for reselecting a Relay UE, where the base station includes:

at least one processor 1600 and at least one memory 1601, wherein the memory stores program code that, when executed by the processor, causes the processor to:

when source Relay UE is connected with Remote UE, determining reselection information, wherein the reselection information is performance information of the source Relay UE or comprises the performance information of the source Relay UE and first channel quality between the Remote UE and the source Relay UE; judging whether to reselect Relay UE aiming at the Remote UE according to the reselection information; wherein the capability information of the source Relay UE includes part or all of the following: the remaining energy of the source Relay UE, the load of the source Relay UE, and a second channel quality between the source Relay UE and the base station.

Optionally, the processor 1700 is further configured to:

judging whether Relay UE reselection is carried out on the Remote UE or not according to the reselection information, and configuring measurement parameters to the Remote UE after the Relay UE reselection is determined to be required to be carried out on the Remote UE; selecting target Relay UE according to the information for selecting the target Relay UE reported by the Remote UE;

the residual energy of the candidate Relay UE, the load of the candidate Relay UE, the first channel quality between the candidate Relay UE and the Remote UE, the second channel quality between the candidate Relay UE and the base station, and the ID of the cell to which the candidate Relay UE belongs.

As shown in fig. 17, an embodiment of the present invention provides a Remote UE for reselecting a Relay UE, where the Remote UE includes:

a determining module 1700, configured to determine reselection information when a source Relay UE is connected to a base station through the source Relay UE, where the reselection information is performance information of the source Relay UE or includes the performance information of the source Relay UE and a first channel quality between the Remote UE and the source Relay UE; wherein the capability information of the source Relay UE includes part or all of the following: the residual energy of the source Relay UE, the load of the source Relay UE, and the quality of a second channel between the source Relay UE and the base station;

a determining module 1700, configured to determine whether to perform reselection of Relay UE for the Remote UE according to the reselection information.

Optionally, the determining module 1700 is further configured to: determining performance information of the source Relay UE in the reselection information by:

Optionally, the determining module 1700 is specifically configured to:

As shown in fig. 18, an embodiment of the present invention provides a base station for reselecting a Relay UE, where the base station includes:

a determining module 1800, configured to determine reselection information when a source Relay UE is connected to a Remote UE through the source Relay UE, where the reselection information is performance information of the source Relay UE or the reselection information includes the performance information of the source Relay UE and a first channel quality between the Remote UE and the source Relay UE; wherein the capability information of the source Relay UE includes part or all of the following: the residual energy of the source Relay UE, the load of the source Relay UE, and the quality of a second channel between the source Relay UE and the base station;

a determining module 1801, configured to determine, according to the reselection information, whether to perform reselection of Relay UE for the Remote UE.

Optionally, the determining module 1801 is specifically configured to:

according to the reselection information, judging whether to reselect Relay UE for the Relay UE, and configuring measurement parameters to the Relay UE after determining that the Relay UE needs to be reselected for the Relay UE; selecting target Relay UE according to the information for selecting the target Relay UE reported by the Remote UE;

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

Accordingly, the subject application may also be embodied in hardware and/or in software (including firmware, resident software, micro-code, etc.). Furthermore, the present application may take the form of a computer program product on a computer-usable or computer-readable storage medium having computer-usable or computer-readable program code embodied in the medium for use by or in connection with an instruction execution system. In the context of this application, a computer-usable or computer-readable medium may be any medium that can contain, store, communicate, propagate, or transport the program for use by or in connection with the instruction execution system, apparatus, or device.

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

Claims

1. A method for reselecting a Relay terminal (Relay UE), the method comprising:

the Remote terminal Remote UE is connected with the base station through the source Relay UE;

the Remote UE determines reselection information, wherein the reselection information is performance information of the source Relay UE or comprises the performance information of the source Relay UE and first channel quality between the Remote UE and the source Relay UE; wherein the capability information of the source Relay UE includes part or all of the following: the residual energy of the source Relay UE, the load of the source Relay UE, and the quality of a second channel between the source Relay UE and the base station;

and the Remote UE judges whether to carry out the reselection of the Relay UE aiming at the Remote UE according to the reselection information.

2. The method of claim 1, wherein the Remote UE determines the performance information of the source Relay UE in the reselection information by:

and the Remote UE receives the performance information sent by the source Relay UE or the base station.

3. The method of claim 1, wherein the Remote UE, after determining whether to perform reselection of Relay UE for the Remote UE according to the reselection information, further comprises:

if the fact that the Relay UE needs to be reselected is determined, the Relay UE determines information for selecting the target Relay UE according to the measurement parameters configured by the base station, selects the target Relay UE according to the information for selecting the target Relay UE, and informs the base station of the selected target Relay UE; or

If the fact that the Relay UE needs to be reselected is determined, the Relay UE determines information for selecting the target Relay UE according to measurement parameters configured by a base station, reports the information for selecting the target Relay UE to the base station, and the base station selects the target Relay UE;

4. A method for reselecting a Relay UE, the method comprising:

the base station is connected with the Remote UE through the source Relay UE;

the base station determines reselection information, wherein the reselection information is performance information of the source Relay UE or comprises the performance information of the source Relay UE and first channel quality between the Remote UE and the source Relay UE; wherein the capability information of the source Relay UE includes part or all of the following: the residual energy of the source Relay UE, the load of the source Relay UE, and the quality of a second channel between the source Relay UE and the base station;

and the base station judges whether to reselect Relay UE aiming at the Remote UE according to the reselection information.

5. The method of claim 4, wherein after the base station determines whether to perform the reselection of the Relay UE for the Remote UE according to the reselection information, the method further comprises:

the base station configures measurement parameters to the Remote UE after determining that the Relay UE needs to be reselected aiming at the Remote UE;

the base station selects target Relay UE according to the information which is reported by the Remote UE and used for selecting the target Relay UE;

6. A Remote UE for reselecting a Relay UE, the Remote UE comprising:

at least one processor and at least one memory, wherein the memory stores program code that, when executed by the processor, causes the processor to perform the following:

7. The Remote UE of claim 6, wherein the processor is specifically configured to:

determining performance information of the source Relay UE in the reselection information by:

8. The Remote UE of claim 6, wherein the processor is further configured to:

9. A base station for reselecting a Relay UE, the base station comprising:

10. The base station of claim 9, wherein the processor is further configured to:

11. A Remote UE for reselecting a Relay UE, the Remote UE comprising:

a determining module, configured to determine reselection information when a source Relay UE is connected to a base station through the source Relay UE, where the reselection information is performance information of the source Relay UE or the reselection information includes the performance information of the source Relay UE and a first channel quality between the Remote UE and the source Relay UE;

a judging module, configured to judge whether to perform reselection of Relay UE for the Remote UE according to the reselection information;

12. A base station for reselecting a Relay UE, the base station comprising:

the device comprises a determining module, a reselection module and a reselection module, wherein the determining module is used for determining reselection information when a source Relay UE is connected with a Remote UE, and the reselection information is performance information of the source Relay UE or comprises the performance information of the source Relay UE and first channel quality between the Remote UE and the source Relay UE;