WO2015003613A1

WO2015003613A1 - Method and device for information transmission and cell search

Info

Publication number: WO2015003613A1
Application number: PCT/CN2014/081822
Authority: WO
Inventors: 傅婧; 刘佳敏
Original assignee: 电信科学技术研究院
Priority date: 2013-07-09
Filing date: 2014-07-08
Publication date: 2015-01-15
Also published as: CN104284392A; CN104284392B

Abstract

The present application is for use in ensuring that a UE that supports a D2D function is allowed to acquire a D2D service in a timely and continuous manner. Disclosed are a method and device for information transmission and cell search. Provided in the present application, the method for information transmission comprises: an evolved node base station (eNB) determines that a cell that is served by the eNB supports an inter-device D2D function; and, the eNB notifies a user equipment (UE) of whether or not the cell that is served by the eNB supports the inter-device D2D function.

Description

Method and device for information transmission and cell search This application claims to be submitted to the Chinese Patent Office on July 09, 2013, the application number is 201310286583.4, and the Chinese patent entitled "A Method and Device for Information Transmission and Cell Search" Priority of the application, the entire contents of which are incorporated herein by reference. Technical field

The present invention relates to the field of communications technologies, and in particular, to a method and an apparatus for information transmission and cell search. Background technique

In the future development of mobile communication systems, in order to better meet the needs of users, improve the efficiency of interactive information, and introduce mechanisms for mutual discovery and even direct communication between mobile devices. The device to device (D2D) service is a new feature introduced in version 12 (R12). The network side device (such as UTRAN (Evolved UMTS Terrestrial Radio Access Network) NB (NodeB) , base station), eNB (evolved NodeB, evolved base station) under re-R12 E-UTRAN, and even some eNBs after R12) do not support this feature. The user equipment (UE) that wants to obtain the D2D service has no mature solution in how to select the network side equipment supporting the D2D service in the mobile process.

Referring to FIG. 1 , in the LTE (Long Term Evolution) system, the centralized control mode of the network is adopted, that is, the uplink and downlink data of the UE are transmitted and received under the control of the network. The communication between the UE and the UE is forwarded and controlled by the network. There is no direct communication link between the UE and the UE, and the UE does not allow itself to send uplink data.

In 3GPP (3rd Generation Partnership Project), D2D proximity services include the following two categories:

ProSe Discovery: The UE uses Evolved Universal Terrestrial Radio Access (E-UTRA) to confirm that another UE is nearby. For example, the D2D UE can use the service to find nearby taxis, looking for them in the attached Near friends;

ProSe Communication: A UE that is close to each other, by directly establishing a link between two UEs, as shown in FIG. 2, thus converting a communication link originally transmitted through the network into a local direct communication link. It saves a lot of bandwidth and network efficiency; or, two UEs close to each other can use direct link communication to obtain stable high-speed and low-cost communication services. Proximity service communication is generally performed under network side control or assistance, and the eNB may even dynamically allocate resources for UEs that are close to service communication.

The D2D proximity service is not only suitable for commercial use UEs, but also for public safety UEs. In the field of public safety, such as public security, fire protection, and ambulance, special discovery and communication processes between terminals are required.

The D2D service is a new feature introduced by R12. Network-side devices (such as NB under UTRAN, eNB under pre-R12 E-UTRAN, and even some eNBs after R12) do not support this feature. The above D2D service is performed under network control or assistance. If the D2D UE for commercial use selects a network that does not support the D2D service, the D2D service cannot be obtained; and for the public safety UE, it is under the network coverage without the D2D service. Some special mechanisms may be used for proximity discovery and communication.

In summary, in the prior art, there is no corresponding mechanism to ensure that the UE supporting the D2D function can obtain the D2D service in a timely manner and continuously. Summary of the invention

The embodiments of the present invention provide a method and a device for information transmission and cell search, which are used to ensure that a UE supporting the D2D function can obtain a D2D service in a timely manner and continuously.

An information sending method provided by an embodiment of the present invention includes:

The evolved base station eNB determines whether the cell served by the eNB supports the inter-device D2D function; the eNB notifies the user equipment UE whether the cell served by the eNB supports the inter-device D2D function. According to the information sending method provided by the embodiment of the present invention, the UE with the D2D function can obtain the D2D service in a timely and continuous manner as much as possible, thereby improving the user experience. Preferably, the eNB broadcasts to the UE, by using a system message, whether the cell served by the eNB supports the D2D function. Therefore, the UE can know whether the cell in its location supports the D2D function.

Preferably, the eNB broadcasts to the UE through the system message whether the cell served by the eNB supports the proximity service discovery function and/or the proximity service communication function. Thereby, the UE can know whether the cell in its location specifically supports the proximity service discovery function and/or the proximity service communication function.

Preferably, the method further includes: the eNB transmitting the D2D parameter to the UE. Therefore, the UE with D2D function, the UE with D2D function enabled, or / and the UE with the highest priority D2D function reside in the D2D cell earlier or longer.

Preferably, the D2D parameter includes a cell reselection parameter. Therefore, the UE with D2D function, the UE with D2D function enabled, or / and the UE with the highest priority D2D function reside in the D2D cell earlier or longer.

Preferably, the D2D parameter further includes a hysteresis value for serving the cell. Therefore, the UE with D2D function, the UE with D2D function enabled, or / and the UE with the highest priority D2D function reside in the D2D cell earlier or longer.

Preferably, for the neighboring cell supporting the D2D function, the D2D parameter further includes an offset value when the neighboring cell is reselected. Therefore, the D2D-capable UE, the D2D-enabled UE, or / and the UE with the highest priority D2D function reside in the D2D cell earlier or longer.

Preferably, the method further includes:

The eNB informs the neighboring cell whether the cell served by the eNB supports the D2D function. Therefore, each cell learns whether its neighboring cell supports D2D function, facilitates cell handover, and selects a suitable D2D cell for the UE.

Preferably, the method further includes:

The eNB knows whether the UE supports the D2D function and/or the priority of the D2D function supported by the UE, and selects the UE that supports the D2D function or the UE that is performing D2D communication or the UE that sets the D2D function to the highest priority during the mobile process. A cell supporting the D2D function serves as a serving cell of the UE. Therefore, the D2D-capable UE, the D2D-enabled UE, or/and the UE with the highest priority D2D function are allowed to reside in the D2D cell as much as possible. Preferably, the method further includes:

When an eNB handover occurs, the source eNB notifies the target eNB of the D2D function priority of the UE it serves.

A cell search method provided by an embodiment of the present invention includes:

The user equipment UE supporting the D2D function between the devices, when determining that the currently camped cell does not support the D2D function, enables the D2D cell selection function and/or the D2D cell reselection function;

The UE selects to camp on the D2D cell according to whether the cell served by the eNB by the evolved base station eNB supports the D2D function.

According to the cell search method provided by the embodiment of the present invention, the UE can obtain the D2D service in a timely and continuous manner, thereby improving the user experience.

Preferably, the UE, when it is determined that the currently camped cell does not support the D2D function, enables the D2D cell selection function and/or the D2D cell reselection function, including:

If the cell currently camped by the UE does not support the D2D function, and the UE has enabled the D2D function and/or sets the D2D function to the highest priority, the UE enables the D2D cell selection function and/or the D2D cell reselection function. . After the UE selects to camp on the cell supporting the related D2D function through the D2D cell, the frequency of the cell is set to the highest priority, and the D2D cell reselection is performed.

Preferably, when the UE starts the D2D cell selection function, the UE selects to camp on the D2D cell according to whether the cell served by the eNB supports the D2D function, and the UE includes: The universal terrestrial radio accesses the E-UTRA frequency point, and reads system information of the best signal quality cell at each E-UTRA frequency point, and determines whether the cell supports the D2D function by using the system information;

The UE selects a cell that camps on a D2D-capable function and satisfies a suitable normal cell condition, and sets the frequency of the zone to the highest priority.

Preferably, when the UE enables the D2D cell reselection function, the UE selects to camp on the D2D cell according to whether the cell served by the eNB supports the D2D function, including:

The UE performs cell reselection only on the searched D2D cell according to whether the cell served by the eNB supports the D2D function notification. Alternatively, if the serving cell or the neighboring cell is a D2D cell, the UE selects to camp on the D2D cell according to whether the cell served by the eNB supports the D2D function and the D2D parameter sent by the eNB.

Preferably, the supporting D2D function, specifically having proximity service discovery capability and/or proximity service communication capability, is:

A UE having only the proximity service discovery capability, when the current camping cell does not support the proximity service discovery function, enables the D2D cell selection function or the D2D cell reselection function; whether the UE supports the D2D according to the cell served by the eNB according to the eNB. Notification of the function, choose to camp on the D2D cell supporting the proximity service discovery function;

A UE having only the service communication capability can enable the D2D cell selection function or the D2D cell reselection function when the current camping cell does not support the proximity service communication function; whether the UE supports the D2D according to the cell served by the eNB according to the eNB. Notification of the function, selecting to camp on the D2D cell supporting the proximity service communication function;

A UE having both a proximity service discovery capability and a proximity service communication capability, when the current camped cell does not support the proximity service discovery function or the proximity service communication function, the D2D cell selection function or the D2D cell reselection function is enabled; the UE according to the eNB Whether the transmitted cell served by the eNB supports the notification of the D2D function, and selects the D2D cell that camps on the proximity service discovery function or the D2D cell that supports the proximity service communication function. Preferably, the method further includes: when the UE reports the UE capability, reporting whether the UE supports the D2D function. The eNB on the network side is made aware of whether the UE supports the D2D function.

Preferably, the method further comprises at least one of the following steps:

If the UE sets the D2D function to the highest priority, the UE informs the eNB through the RRC message that the UE sets the D2D function to the highest priority; thus, the UE can select the D2D cell as the serving cell as much as possible.

When the UE cancels the D2D function to the highest priority, the UE informs the eNB through the RRC message that the UE cancels the D2D function to the highest priority; thus, the UE can select the D2D cell that is interested in the UE as the serving cell.

After the cell handover, if the UE does not report that the D2D function is set to the highest priority before the cell handover, the UE informs the eNB to which the currently camped cell belongs to the UE to set the D2D function to the highest priority through the RRC message. Thereby, the UE can be selected as much as possible to select the D2D cell as the serving cell.

An evolved base station eNB according to an embodiment of the present invention includes:

And a determining unit, configured to determine whether the cell served by the eNB supports the inter-device D2D function, and the notification unit is configured to notify the user equipment, whether the cell served by the eNB supports the inter-device D2D function.

The eNB provided by the embodiment of the present invention ensures that the D2D-capable UE can obtain the D2D service in a timely manner and continuously, thereby improving the user experience.

Preferably, the determining unit may be a processor such as a CPU. The notification unit may be an information transmitting device such as an antenna.

Preferably, the notification unit broadcasts to the UE, through the system message, whether the cell served by the eNB supports the D2D function.

Preferably, the notification unit broadcasts to the UE, by the system message, whether the cell served by the eNB supports the proximity service discovery function and/or the proximity service communication function.

Preferably, the notification unit is further configured to:

The D2D parameters are sent to the UEs in the cell supporting the D2D function.

Preferably, the D2D parameter includes a cell reselection parameter. Preferably, the D2D parameter further includes a hysteresis value for serving the cell.

Preferably, for the neighboring cell supporting the D2D function, the D2D parameter further includes an offset value when the neighboring cell is reselected.

Preferably, the notification unit is further configured to:

The neighboring cell is notified whether the cell served by the eNB supports the D2D function.

Preferably, the determining unit is further configured to:

Knowing whether the UE supports the D2D function and/or the priority of the D2D function supported by the UE, and selects support for the UE supporting the D2D function or the UE performing D2D communication or the UE setting the D2D function to the highest priority during the mobile process. The D2D function cell serves as the serving cell of the UE.

Preferably, the notification unit is further configured to:

When an eNB handover occurs, the D2D function priority of the UE served by the source eNB is notified to the target eNB.

An embodiment of the present invention provides an evolved base station eNB, including a processor and a data transceiver, where:

The processor is configured to: determine whether the cell served by the eNB supports inter-device D2D function; notify the user equipment UE whether the cell served by the eNB supports inter-device D2D function;

The data transceiver is configured to implement data transmission between the processor and the UE.

A user equipment UE provided by the embodiment of the present invention includes:

The D2D function unit is enabled to enable the D2D cell selection function and/or the D2D cell reselection function when the UE supports the D2D function between the devices and determines that the cell currently camped by the UE does not support the D2D function;

The cell selection unit is configured to select to camp on the D2D cell according to whether the cell served by the eNB transmitted by the evolved base station eNB supports the D2D function.

According to the UE provided by the embodiment of the present invention, the UE can obtain the D2D service in a timely manner and continuously, thereby improving the user experience.

Preferably, the enabled D2D functional unit and the cell selection unit are all implemented by a processor such as a CPU. If the cell currently camped by the UE does not support the D2D function, and the UE turns on the D2D function and/or sets the D2D function to the highest priority, the D2D function unit turns on the D2D cell selection function and/or the D2D cell. Reselect function.

Preferably, when the D2D function unit is enabled to enable the D2D cell selection function, the cell selection unit is specifically configured to:

Searching for the evolved universal terrestrial radio access E-UTRA frequency points, and reading the system information of the signal quality optimal cell on each E-UTRA frequency point, and determining whether the cell supports the D2D function by using the system information;

The cell that is camped on to support the D2D function and satisfies the appropriate normal cell condition is selected, and the frequency of the cell is set to the highest priority.

Preferably, when the D2D function unit is enabled to enable the D2D cell reselection function, the cell selection unit is specifically configured to:

Performing cell reselection only on the searched D2D cell according to whether the cell served by the eNB supports the D2D function notification;

Or, if the serving cell or the neighboring cell is a D2D cell, the camping is performed according to whether the cell served by the eNB supports the D2D function, and the D2D parameter sent by the eNB is selected to camp on the D2D cell.

Preferably, the D2D parameter includes a cell reselection parameter.

Preferably, the D2D parameter further includes a hysteresis value for serving the cell.

The UE having only the proximity of the service discovery capability, when the current camping cell does not support the proximity service discovery function, enables the D2D function unit to enable the D2D cell selection function or the D2D cell reselection function; the cell selection unit is served by the eNB according to the eNB. Whether the cell supports the notification of the D2D function, and chooses to camp the UE to the D2D cell supporting the proximity service discovery function; A UE having only the proximity service communication capability, when the current camping cell does not support the proximity service communication function, turning on the D2D function unit to enable the D2D cell selection function or the D2D cell reselection function; the cell selection unit is served by the eNB according to the eNB. Whether the cell supports the notification of the D2D function, selecting to camp the UE to the D2D cell supporting the proximity service communication function, and then turning off the D2D cell selection function;

A UE having both a proximity service discovery capability and a proximity service communication capability, when the current camping cell does not support the proximity service discovery function or the proximity service communication function, the D2D function unit is enabled to enable the D2D cell selection function or the D2D cell reselection function; The selecting unit selects to camp on the D2D cell supporting the proximity service discovery function or the D2D cell supporting the proximity service communication function according to the notification sent by the eNB whether the cell served by the eNB supports the D2D function, and then close the D2D cell selection function. .

Preferably, the UE further includes:

The reporting unit is configured to report whether the UE supports the D2D function when the UE capability reports. Preferably, the reporting unit is further configured to perform at least one of the following steps:

If the UE sets the D2D function to the highest priority, the eNB is notified by the RRC message that the UE sets the D2D function to the highest priority;

When the UE cancels the D2D function as the highest priority, the eNB is notified by the RRC message that the UE cancels the D2D function as the highest priority;

After the cell handover, if the UE does not report that the D2D function is set to the highest priority before the cell handover, the eNB informs the eNB to which the currently camped cell belongs to the UE to set the D2D function to the highest priority.

A user equipment (UE) includes a processor and a data transceiver, where: the processor is configured to: when the UE supports inter-device D2D function and determines that the cell currently camped by the UE does not support When the D2D function is enabled, the D2D cell selection function and/or the D2D cell reselection function is enabled; and the camping to the D2D cell is selected according to whether the cell served by the eNB by the evolved base station eNB supports the D2D function.

The data transceiver transmits and receives data under the control of the processor. In summary, the technical solution provided by the embodiment of the present invention ensures that the UE with the D2D function can obtain the D2D service in a timely and continuous manner as much as possible, thereby improving the user experience. DRAWINGS

1 is a schematic diagram of the principle of an existing mobile communication system;

2 is a schematic diagram of the principle of existing D2D communication;

FIG. 3 is a schematic flowchart of a method for sending information according to an embodiment of the present disclosure;

4 is a schematic flowchart of a cell search method according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of an eNB according to an embodiment of the present disclosure;

FIG. 5B is a schematic structural diagram of a corresponding implementation of an eNB according to an embodiment of the present invention;

FIG. 6 is a schematic structural diagram of a UE according to an embodiment of the present disclosure;

FIG. 6B is a schematic structural diagram of a corresponding implementation of a UE according to an embodiment of the present invention. detailed description

The technical solution proposed by the embodiment of the present invention is a mechanism for supporting D2D service continuity, thereby ensuring that the D2D UE obtains the D2D service in a timely manner and continuously.

In the embodiment of the present invention, the eNB broadcasts a corresponding indication to inform the UE whether the current base station supports the related D2D function. The eNB broadcasts a special cell reselection parameter for the D2D-enabled cell (referred to as a D2D cell for short), so that the UE can be quickly stabilized. The UE is in the D2D cell, and the eNB is informed of the priority of the D2D function, so that the eNB selects the D2D cell as the serving cell as much as possible according to the capability, state, or UE reporting of the UE; The broadcast indication and its own state, the operation of the associated preferred D2D cell is performed at the time of cell reselection.

Referring to FIG. 3, on the eNB side, an information sending method provided by an embodiment of the present invention includes:

S101. The evolved base station eNB determines whether a cell served by the eNB supports an inter-device D2D function. S102. The eNB notifies the user equipment, whether the cell served by the eNB supports the inter-device D2D function.

Preferably, the eNB broadcasts to the UE through the system message whether the cell served by the eNB supports the D2D function.

Preferably, the eNB broadcasts to the UE, by using a system message, whether the cell served by the eNB supports the D2D function, including:

The eNB broadcasts to the UE through the system message whether the cell served by the eNB supports the proximity service discovery function and/or the proximity service communication function.

Preferably, the method further includes:

The eNB transmits the D2D parameters to the UEs in the cell supporting the D2D function.

Preferably, the D2D parameter includes a cell reselection parameter.

Preferably, the D2D parameter further includes a hysteresis value for the serving cell served by the eNB. Preferably, for the neighboring cell of the serving cell served by the D2D-enabled eNB, the D2D parameter further includes an offset value when the neighboring cell is reselected.

Preferably, the method further includes:

The eNB informs the neighboring cell whether the cell served by the eNB supports the D2D function, and the eNB to which the neighboring cell belongs can receive the notification.

Preferably, the method further includes:

The eNB learns whether the UE supports the D2D function and/or the priority of the D2D function supported by the UE, and is a D2D-capable UE or a D2D-capable UE and supports D2D function and D2D function during the mobile process. The UE set to the highest priority selects a cell supporting the D2D function as the serving cell of the UE.

Preferably, the method further includes:

Correspondingly, on the UE side, referring to FIG. 4, a cell selection method according to an embodiment of the present invention includes: 5201. The user equipment UE supporting the D2D function between the devices, when determining that the currently camped cell does not support the D2D function, enabling the D2D cell selection function and/or the D2D cell reselection function to perform the cell selection process and/or the cell reselection. process;

5202. In the cell selection process and/or the cell reselection process, the UE selects to camp on the D2D cell according to whether the cell served by the eNB by the evolved base station eNB supports the D2D function.

Preferably, the UE is an idle UE.

If the cell currently camped by the UE does not support the D2D function, and the UE has enabled the D2D function and/or sets the D2D function to the highest priority, the UE enables the D2D cell selection function and/or the D2D cell reselection function. .

Preferably, when the UE starts the D2D cell selection function, the UE selects to camp on the D2D cell according to whether the cell served by the eNB supports the D2D function, and includes:

The UE searches for the evolved universal terrestrial radio access E-UTRA frequency point available around, and reads system information of the signal quality optimal cell on each E-UTRA frequency point, and determines whether the cell supports D2D through the system information. Features;

Preferably, when the UE performs the D2D cell reselection function, the UE selects to camp on the D2D cell according to the notification that the cell served by the eNB supports the D2D function, including the eNB, in performing the cell reselection process. :

The UE performs cell reselection only on the searched D2D cell according to whether the cell served by the eNB supports the D2D function notification.

Or, if the serving cell or the neighboring cell is a D2D cell, the UE sends a notification according to whether the cell served by the eNB supports the D2D function, and the D2D parameter sent by the eNB, according to the eNB, Choose to camp on the D2D cell.

Preferably, the D2D parameter includes a cell reselection parameter.

A UE having both a proximity service discovery capability and a proximity service communication capability, when the current camped cell does not support the proximity service discovery function or the proximity service communication function, the D2D cell selection function or the D2D cell reselection function is enabled; the UE according to the eNB Whether the transmitted cell served by the eNB supports the notification of the D2D function, and selects the D2D cell that camps on the proximity service discovery function or the D2D cell that supports the proximity service communication function.

Preferably, when the UE is a connected UE, the method further includes:

When the UE reports the UE capability, it reports whether it supports the D2D function.

Preferably, when the UE is a connected UE, the method further includes at least one of the following steps: If the UE sets the D2D function to the highest priority, the UE informs the eNB by using an RRC message that the UE sets the D2D function to the highest priority. Level

When the UE cancels the D2D function to the highest priority, the UE informs the eNB by the RRC message that the UE cancels the D2D function as the highest priority; After the cell handover, if the UE does not report that the D2D function is set to the highest priority before the cell handover, the UE informs the eNB to which the currently camped cell belongs to the UE to set the D2D function to the highest priority through the RRC message.

An introduction to a specific embodiment of the present invention is given below.

Example 1

The RRC idle (idle) state, the D2D-capable UE performs D2D cell selection.

The eNB broadcasts a corresponding indication, and informs the UE whether the current base station supports the related D2D function. If the current camped cell does not support the related D2D function, the UE starts the D2D cell selection function, and the UE selects the D2D cell through the D2D cell. After leaving the cell supporting the relevant D2D function, the frequency point where the cell is located is set to the highest priority, and D2D cell reselection is performed.

Network side:

Through the system message (such as SIB1 or new SIB), the eNB broadcasts the cell to support the D2D function; since the D2D service is further divided into the proximity service discovery and the proximity service communication, the support service discovery function and/or may be further indicated in the system message. Support for proximity service communication.

UE side:

The RRC idle state UE supporting the D2D function, if the current camping cell does not support the D2D function, the UE starts the D2D cell selection process or the D2D cell reselection process.

The D2D cell selection process is specifically: not considering the cell reselection priority, but searching all available E-UTRA frequency points according to its capability, and at least the signal quality optimal cell reading system for each E-UTRA frequency point. The information confirms whether it supports the D2D function. If the cell with the best signal quality (or the highest order) at a certain frequency point supports the D2D function and satisfies the condition of the suitable cell, the UE selects the cell, and the cell is located. The frequency is set to the highest priority, and the D2D cell selection function is stopped, and the D2D cell reselection process is performed. If a suitable D2D cell is not found, the UE may perform the D2D cell selection function regularly, and the period may be implemented by the UE.

If the network side further supports the D2D function to support the proximity service discovery function and/or the proximity service communication function, the UE side initiates D2D cell selection and/or D2D according to its own functions and the D2D function of the network side. The conditions and processes of the cell reselection function have changed somewhat. Chemical. For example, a UE with proximity service discovery capability initiates D2D cell selection and/or D2D cell reselection when the camped cell does not support the proximity service discovery function. In the D2D cell selection process, the selective proximity service discovery function also needs to be selected. The D2D cell will stop the D2D cell selection function. For UEs with proximity to service communication capabilities, the conditions and procedures for initiating D2D selection and/or D2D cell reselection are similarly changed. If the UE has both proximity service discovery capability and proximity service communication capability, the UE only needs to select to support proximity service. Discover the function or the cell that supports the service communication function.

The D2D cell reselection process can be implemented in two ways:

The first type: In the D2D cell reselection process, the UE only performs cell reselection judgment on the searched D2D cell, and the cell reselection determination rule is the same as the existing cell reselection rule; only there is no suitable D2D cell at present. At the same time, the ordinary cell selection or reselection process is performed, and the above D2D cell selection process is simultaneously performed;

The second type: In the D2D cell reselection process, if the serving cell or the neighboring cell is a D2D cell, the special D2D parameter is added when the cell is reselected, so that the UE can select the D2D cell for a longer time and more easily. See Embodiment 3 (Note: In this process, a D2D cell and a normal cell are included).

Example 2

In the RRC idle state, the UE that enables the D2D function performs D2D cell selection.

Different from Embodiment 1, when the D2D-enabled UE enables the D2D function, or/and the UE sets the D2D function to the highest priority, the UE starts the D2D if the current camping cell does not support the related D2D function. Cell selection function or D2D cell reselection process.

Network side:

The eNB broadcasts the cell to support the D2D function through a system message (such as SIB1 or a new SIB); or broadcasts the cell to support the proximity service discovery function and/or the proximity service communication function.

UE side:

The RRC idle state UE supporting the D2D function, if the D2D function is not enabled, or/and the UE does not set the D2D function to the highest priority, the UE performs only normal cell reselection; when the UE starts D2D When the function, or/and the UE sets the D2D function to the highest priority, if the current camping cell does not support the related D2D function, the UE starts the D2D cell selection function or the D2D cell reselection process, and the D2D cell selection process and the embodiment 1 is the same, the possible difference is that the D2D cell selection period may be implemented by the UE or by the D2D service application layer; after the UE selects the D2D cell, the D2D cell reselection is performed subsequently, as in Embodiment 1.

When the UE turns off the D2D function, or when the UE no longer sets the D2D function to the highest priority, the UE correspondingly closes the D2D cell selection process or the D2D cell reselection process (if it is currently in progress), and the related D2D is no longer used. The frequency at which the cell is located is set to the highest priority.

If the network side will further support the D2D function to support the proximity service discovery function and/or support the proximity service communication function, there are some changes in the conditions and procedures for initiating the D2D cell selection function or D2D cell reselection, such as UEs with proximity service discovery capability. When the UE turns on the proximity service discovery function, or/and the UE sets the proximity service discovery function to the highest priority, the D2D cell selection function or the D2D cell reselection is enabled; the D2D cell selection process is also for finding the support proximity service discovery function. D2D cell.

Example 3

The eNB broadcasts special cell reselection parameters for supporting D2D functions.

The eNB broadcasts some special cell reselection parameters for D2D cell reselection, so that the D2D-capable UE, the D2D-enabled UE, or/and the D2D function as the highest priority (or interested) UE, earlier The longer or longer camping on the D2D cell; after the UE camps on the D2D cell, if the frequency point of the cell is not the highest priority, the frequency point is set to the highest priority.

For example, if the offset of the D2D cell is increased, the UE can more easily select the D2D cell when performing cell reselection of the same frequency or the same frequency.

Network side:

In addition to broadcasting the existing cell reselection parameters, if the eNB has the D2D function, it broadcasts an additional hysteresis value of the serving cell priority parameter Qhyst_D2D; if there is a neighboring area with D2D function, an additional broadcast is broadcast for the neighboring area. The offset value (offset) of the neighboring cell priority parameter, that is, Qoffsets, n - D2D.

UE side:

Currently, the Idle state UE performs cell reselection through the R criterion when performing cell reselection of the same frequency or the same priority inter-frequency. In the R criterion, Rs represents the priority parameter of the serving cell, and Rn represents the priority parameter of the neighboring cell, which is defined as follows:

Rs— Qmeas,s + QHyst

Rn = Qmeas,n - Qoffset where: Qmeas represents the cell reselection reference signal received power (RSRP) measurement. QHyst indicates the hysteresis value, which is set for the serving cell. It can be understood that when a cell is used as a serving cell, there is a hysteresis to prevent the ping-pong effect.

The Qoffset represents an offset for calculating the R value of the neighboring cell. For the same-frequency cell, if the offset value of the neighboring cell priority parameter is Qoffsets, n is valid, then Qoffset is Qoffsets, n, otherwise Qoffset is 0; Inter-frequency cell, if Qoffsets, n is valid, then Qoffset = Qoffsets, n + Qoffsetfrequency; otherwise Qoffset: Qoffsetfrequency. Where Qoffsetfrequency is the preset frequency offset.

The R criterion is a criterion specified in the existing protocol, and the R value formula obtained by the serving cell and the neighboring cell is as shown in the box. When the UE performs cell reselection, the R value is sorted, and the selected value is the largest. That serves as a service community.

Each of the above parameters can be notified to the UE after being pre-configured by the network side base station.

When performing cell reselection, the UE needs to compare the priority parameters of each cell and select the cell corresponding to the largest priority parameter.

The UE sorts all cells that satisfy the S criterion. If a cell is sorted as the best cell, the UE reselects the cell to the cell.

In the case of a UE with D2D, a UE with D2D enabled, or / and a UE with the D2D function set to the highest priority (or interested), the R sorting formula becomes (red is the increasing part):

Rs = Qmeas,s + QHyst + QHyst— D2D Rn = Qmeas, n - Qoffset, where Qoffsets when Qoffset is calculated, n is the original Qoffsets, n plus Qoffsets, n - D2D, or directly Qoffsets, n - D2D.

Thus, since the offset value is added to the cell having the D2D function, and the corresponding R value (Rs or Rn) is increased, the UE can camp on the D2D cell earlier or longer.

After the UE camps on the D2D cell, if the frequency point at which the cell is located is not the highest priority, the frequency point is set to the highest priority; when the UE leaves the D2D cell camping on other frequency points, or the D2D function is turned off; or When D2D is no longer of interest, the highest priority setting of the frequency point is canceled, and the original priority is restored.

Broadcasting a special cell reselection parameter for the D2D cell, including not only the offset in the R criterion, but also other cell reselection parameters, such as a D2D cell broadcast special Snonintrasearch, if the UE resides in the current D2D cell, if the service When the S value of the cell is larger than Snonintrasearch, the measurement of the same priority or the lower priority frequency is not performed. When the cell of the high priority frequency is reselected, special parameters are set for the D2D cell.

Example 4

In the RRC connected state, the eNB guarantees continuity according to the capabilities of the UE.

During the mobile process, the eNB selects the D2D cell as the serving cell for the UE supporting the D2D function or the D2D-capable UE.

UE side:

Network side:

The eNB mutually informs whether the cell serving as a neighboring cell supports the D2D function;

The eNB obtains whether the UE supports the D2D function by using the UE capability; since the D2D is controlled by the eNB, the eNB can determine whether the UE is performing D2D;

During the mobile process, the eNB supports the D2D cell as the serving cell as much as possible for the UE supporting the D2D function or the UE performing the D2D communication.

Example 5

In the RRC connected state, the eNB guarantees continuity according to the priority reported by the UE. The connected UE informs the eNB of its preference, and the UE selects the D2D cell as the serving cell as much as possible for the UE that sets the D2D function to the highest priority (or is interested) during the mobile process.

UE side:

If the UE sets the D2D function to the highest priority, the UE informs the eNB through the RRC message; when the UE cancels the D2D function as the highest priority, the eNB needs to be notified by a message. After the handover occurs, the UE also needs an RRC message to inform the eNB whether the current D2D function is the highest priority (or interested) if it has not been previously selected.

Network side:

The eNB mutually informs whether the cell as a neighboring area supports the D2D function;

When a handover occurs, the source eNB informs the target eNB of the D2D function priority (or interest) of the UE through the inter-node message;

The eNB sets the D2D function to the highest priority (or interest) during the move.

The UE tries to select the D2D cell as the serving cell.

Referring to FIG. 5A, an evolved base station eNB according to an embodiment of the present invention includes: a determining unit 11 configured to determine whether a cell served by the eNB supports an inter-device D2D function; and a notification unit 12, configured to notify a user equipment Whether the UE supports the inter-device D2D function by the cell served by the eNB.

Preferably, the notification unit 12 broadcasts to the UE, through the system message, whether the cell served by the eNB supports the D2D function.

Preferably, the notification unit 12 broadcasts to the UE, through the system message, whether the cell served by the eNB supports the proximity service discovery function and/or the proximity service communication function.

Preferably, the notification unit 12 is further configured to:

The D2D parameters are sent to the UEs in the cell supporting the D2D function.

Preferably, the D2D parameter includes a cell reselection parameter.

Preferably, for the neighboring cell supporting the D2D function, the D2D parameter further includes an offset value when the neighboring cell is reselected. Preferably, the notification unit 12 is further configured to:

Preferably, the determining unit 11 is further configured to:

Preferably, the notification unit 12 is further configured to:

An embodiment of the present invention provides an evolved base station eNB, as shown in FIG. 5B, including a processor 500 and a data transceiver 510, where:

The processor 500 is configured to: determine whether the cell served by the eNB supports the inter-device D2D function; notify the user equipment UE whether the cell served by the eNB supports the inter-device D2D function; the data transceiver 510 is configured to implement the processing Data transfer between the device and the UE.

In Figure 5B, the bus architecture can include any number of interconnected buses and bridges, specifically linked by one or more processors represented by processor 500 and various circuits of memory represented by memory 520. The bus architecture can also link various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and, therefore, will not be further described herein. The bus interface provides an interface. Data transceiver 710 can be a plurality of components, including a transmitter and a receiver, providing means for communicating with various other devices on a transmission medium. The processor 500 is responsible for managing the bus architecture and general processing, and the memory 520 can store data used by the processor 500 when performing operations.

Referring to FIG. 6A, a user equipment UE is provided in the embodiment of the present invention. The UE includes: an D2D function unit 21, configured to: when the UE supports D2D function between devices, and determines that a cell currently camped by the UE does not support D2D function. When the D2D cell selection function and/or the D2D cell reselection function is enabled;

a cell selection unit 22, configured to send, according to the evolved base station eNB, a small service served by the eNB Whether the zone supports the notification of the D2D function, and chooses to camp on the D2D cell.

Preferably, the UE is an idle UE.

Preferably, if the cell currently camped by the UE does not support the D2D function, and the UE has enabled the D2D function and/or sets the D2D function to the highest priority, the D2D function unit turns on the D2D cell selection function and / or D2D cell reselection function.

Preferably, when the D2D function unit is enabled to enable the D2D cell selection function, the cell selection unit 22 is specifically configured to:

Preferably, the D2D parameter includes a cell reselection parameter.

Only the UE with the proximity service discovery capability enables the D2D function unit to enable the D2D cell selection function or the D2D cell reselection function when the current camping cell does not support the proximity service discovery function; The cell selection unit selects to camp the UE to the D2D cell supporting the proximity service discovery function according to whether the cell served by the eNB supports the D2D function.

A UE having only the proximity service communication capability, when the current camping cell does not support the proximity service communication function, turning on the D2D function unit to enable the D2D cell selection function or the D2D cell reselection function; the cell selection unit is served by the eNB according to the eNB. Whether the cell supports the notification of the D2D function, and selects to camp the UE to the D2D cell supporting the proximity service communication function;

A UE having both a proximity service discovery capability and a proximity service communication capability, when the current camping cell does not support the proximity service discovery function or the proximity service communication function, the D2D function unit is enabled to enable the D2D cell selection function or the D2D cell reselection function; The selection unit selects to camp on the D2D cell supporting the proximity service discovery function or the D2D cell supporting the proximity service communication function according to the notification sent by the eNB whether the cell served by the eNB supports the D2D function.

Preferably, when the UE is a connected UE, the UE further includes:

The reporting unit 23 is configured to report whether the UE supports the D2D function when the UE capability reports. Preferably, when the UE is a connected UE, the reporting unit 23 is further configured to perform at least one of the following steps:

A user equipment UE, as shown in FIG. 6B, includes a processor 600 and a data transceiver 610, where:

The processor 600 is configured to: when the UE supports the inter-device D2D function and determines that the cell currently camped by the UE does not support the D2D function, enable the D2D cell selection function and/or the D2D cell reselection function; according to the evolved type Whether the cell served by the eNB transmitted by the base station eNB supports D2D Notification of the function, choose to camp on the D2D cell;

The data transceiver 610 transmits and receives data under the control of the processor 600.

In Figure 6B, the bus architecture can include any number of interconnected buses and bridges, specifically linked by one or more processors represented by processor 600 and various circuits of memory represented by memory 620. The bus architecture can also link various other circuits such as peripherals, voltage regulators, and power management circuits, which are well known in the art and, therefore, will not be further described herein. The bus interface provides an interface. Data transceiver 610 can be a plurality of components, including a transmitter and a receiver, providing means for communicating with various other devices on a transmission medium. The processor 600 is responsible for managing the bus architecture and general processing, and the memory 620 can store data used by the processor 600 in performing operations.

In summary, the present invention provides a mechanism for supporting D2D service continuity, allowing D2D UEs to stay or connect to D2D cells as much as possible during the mobile process, thereby ensuring that D2D UEs can obtain D2D in a timely and continuous manner. Service, enhance the user experience.

Those skilled in the art will appreciate that embodiments of the present invention can be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or a combination of software and hardware. Moreover, the invention can be embodied in the form of one or more computer program products embodied on a computer-usable storage medium (including but not limited to disk storage and optical storage, etc.) in which computer usable program code is embodied.

The present invention has been described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (system), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flowcharts and/or block diagrams, and combinations of flow and/or blocks in the flowcharts and/or block diagrams can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing device to produce a machine for the execution of instructions for execution by a processor of a computer or other programmable data processing device. Means for implementing the functions specified in one or more of the flow or in a block or blocks of the flow chart.

These computer program instructions can also be stored in a bootable computer or other programmable data processing device. In a computer readable memory that operates in a particular manner, causing instructions stored in the computer readable memory to produce an article of manufacture comprising instruction means implemented in one or more flows and/or block diagrams of the flowchart The function specified in the box or in multiple boxes.

These computer program instructions can also be loaded onto a computer or other programmable data processing device such that a series of operational steps are performed on a computer or other programmable device to produce computer-implemented processing for execution on a computer or other programmable device. The instructions provide steps for implementing the functions specified in one or more of the flow or in a block or blocks of a flow diagram. The spirit and scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of the inventions

Claims

Rights request

1. An information sending method, characterized in that the method includes:

The evolved base station eNB determines whether the cell served by the eNB supports the inter-device D2D function; the eNB notifies the user equipment UE whether the cell served by the eNB supports the inter-device D2D function.

2. The method according to claim 1, characterized in that the eNB broadcasts to the UE whether the cell served by the eNB supports the D2D function through a system message.

3. The method according to claim 2, characterized in that the eNB broadcasts to the UE whether the cell served by the eNB supports the D2D function through a system message, including:

The eNB broadcasts to the UE through system messages whether the cell served by the eNB supports the proximity service discovery function and/or the proximity service communication function.

4. The method according to claim 1, characterized in that, the method further includes:

The eNB sends the D2D parameters to the UE.

5. The method according to claim 4, characterized in that the D2D parameters include cell reselection parameters.

6. The method according to claim 5, characterized in that the D2D parameters further include a hysteresis value for the serving cell.

7. The method according to claim 5 or 6, characterized in that, for a neighboring cell that supports the D2D function, the D2D parameters also include an offset value during cell reselection of the neighboring cell.

8. The method according to claim 1, characterized in that, the method further includes:

The eNB notifies neighboring cells whether the cell served by the eNB supports the D2D function.

9. The method according to claim 1, characterized in that, the method further includes:

The eNB learns whether the UE supports the D2D function and/or the priority of the D2D function supported by the UE, and during the movement process, it selects the UE that supports the D2D function or the UE that is conducting D2D communication or the UE that sets the D2D function to the highest priority. The cell that supports the D2D function serves as the serving cell for the UE.

10. The method according to claim 1, characterized in that, the method further includes: When an eNB handover occurs, the source eNB notifies the target eNB of the D2D function priority of the UE it serves.

11. A cell search method, characterized in that the method includes:

The user equipment UE that supports the inter-device D2D function, when it is determined that the cell currently camped on does not support the D2D function, turns on the D2D cell selection function and/or the D2D cell reselection function;

The UE selects to camp on the D2D cell based on the notification sent by the evolved base station eNB whether the cell served by the eNB supports the D2D function.

12. The method according to claim 11, characterized in that, when the UE determines that the cell currently camped on does not support the D2D function, the D2D cell selection function and/or the D2D cell reselection function is enabled, including:

If the cell where the UE is currently camping does not support the D2D function, and the UE has enabled the D2D function and/or set the D2D function to the highest priority, then the UE enables the D2D cell selection function and/or the D2D cell reselection function. .

13. The method according to claim 11, characterized in that when the UE turns on the D2D cell selection function, the UE selects to camp on the D2D cell according to the notification sent by the eNB whether the cell served by the eNB supports the D2D function. , include:

The UE searches for available E-UTRA frequency points around it, reads the system information of the cell with the best signal quality on each E-UTRA frequency point, and uses the system information to determine whether the cell supports D2D. Function;

The UE selects to camp on a cell that supports the D2D function and meets suitable cell conditions, and sets the frequency point of the cell to the highest priority.

14. The method according to claim 11, characterized in that when the UE turns on the D2D cell reselection function, the UE selects to camp on the D2D based on the notification sent by the eNB whether the cell served by the eNB supports the D2D function. Community, including:

The UE only performs cell reselection on the searched D2D cells based on the notification sent by the eNB whether the cell served by the eNB supports the D2D function;

Or, if the serving cell or neighboring cell is a D2D cell, the UE sends Based on the notification of whether the cell served by the eNB supports the D2D function and the D2D parameters sent by the eNB, the D2D cell is selected to camp on.

15. The method according to claim 14, characterized in that the D2D parameters include cell reselection parameters.

16. The method according to claim 15, wherein the D2D parameters further include a hysteresis value for the serving cell.

17. The method according to claim 15 or 16, characterized in that, for a neighboring cell that supports the D2D function, the D2D parameters also include an offset value during cell reselection of the neighboring cell.

18. The method according to claim 11, wherein the supporting D2D function specifically includes proximity service discovery capabilities and/or proximity service communication capabilities, then:

A UE that only has Proximity Service Discovery capability enables the D2D cell selection function or the D2D cell reselection function when the current resident cell does not support the Proximity Service Discovery function; the UE determines whether the cell served by the eNB supports D2D based on the information sent by the eNB. Function notification, choose to camp on a D2D cell that supports proximity service discovery function;

A UE that only has ProSe communication capability turns on the D2D cell selection function or the D2D cell reselection function when the current resident cell does not support the ProSe communication function; the UE determines whether the cell served by the eNB supports D2D based on the information sent by the eNB. Function notification, choose to camp on a D2D cell that supports proximity service communication function;

A UE that has both ProSe discovery capability and ProSe communication capability turns on the D2D cell selection function or the D2D cell reselection function when the current resident cell does not support the ProSe discovery function or the ProSe communication function; the UE activates the D2D cell selection function or D2D cell reselection function according to the eNB The sent notification of whether the cell served by the eNB supports the D2D function is selected to camp on a D2D cell that supports the ProSe discovery function or a D2D cell that supports the ProSe communication function.

19. The method according to claim 11, characterized in that, the method further includes:

When reporting the UE capabilities, the UE reports whether it supports the D2D function.

20. The method according to claim 11, characterized in that, the method further includes at least one of the following steps: If the UE sets the D2D function to the highest priority, the UE notifies the eNB that the UE sets the D2D function to the highest priority through the RRC message;

When the UE cancels setting the D2D function as the highest priority, the UE informs the eNB through the RRC message that the UE cancels setting the D2D function as the highest priority;

After cell handover, if the UE does not report that it has set the D2D function to the highest priority before the cell handover, the UE will notify the eNB of the cell where it is currently camping through an RRC message that the UE has set the D2D function to the highest priority.

21. An evolved base station eNB, characterized in that the eNB includes:

The determination unit is used to determine whether the cell served by the eNB supports the inter-device D2D function; the notification unit is used to notify the user equipment UE whether the cell served by the eNB supports the inter-device D2D function.

22. The eNB according to claim 21, characterized in that the notification unit broadcasts to the UE whether the cell served by the eNB supports the D2D function through a system message.

23. The eNB according to claim 22, characterized in that the notification unit broadcasts to the UE through a system message whether the cell served by the eNB supports the ProSe discovery function and/or the ProSe communication function.

24. The eNB according to claim 21, wherein the notification unit is further configured to: send D2D parameters to the UE in the cell that supports the D2D function.

25. The eNB according to claim 24, wherein the D2D parameters include cell reselection parameters.

26. The eNB according to claim 25, wherein the D2D parameters further include a hysteresis value for the serving cell.

27. The eNB according to claim 25 or 26, characterized in that, for a neighboring cell that supports the D2D function, the D2D parameters also include an offset value during cell reselection of the neighboring cell.

28. The eNB according to claim 21, wherein the notification unit is further configured to: notify neighboring cells whether the cell served by the eNB supports the D2D function.

29. The eNB according to claim 21, wherein the determining unit is further configured to: Learn whether the UE supports the D2D function and/or the priority of the D2D function supported by the UE, and select support for the UE that supports the D2D function or the UE that is conducting D2D communication or the UE that sets the D2D function to the highest priority during movement. The cell with D2D function serves as the serving cell for the UE.

30. The eNB according to claim 21, wherein the notification unit is further configured to: when an eNB handover occurs, notify the target eNB of the D2D function priority of the UE served by the source eNB.

31. A user equipment UE, characterized in that the UE includes:

Turn on the D2D functional unit, used to turn on the D2D cell selection function and/or the D2D cell reselection function when the UE supports the inter-device D2D function and determines that the cell where the UE currently resides does not support the D2D function;

The cell selection unit is used to select a D2D cell to camp on based on the notification sent by the evolved base station eNB of whether the cell served by the eNB supports the D2D function.

32. The UE according to claim 31, characterized in that, if the cell where the UE currently camps does not support the D2D function, and the UE has enabled the D2D function and/or set the D2D function to the highest priority, then The enable D2D functional unit enables the D2D cell selection function and/or the D2D cell reselection function.

33. The UE according to claim 31, characterized in that when the D2D functional unit is turned on to enable the D2D cell selection function, the cell selection unit is specifically used to:

Search for available Evolved Universal Terrestrial Radio Access E-UTRA frequency points around, and read the system information of the cell with the best signal quality on each E-UTRA frequency point, and use the system information to determine whether the cell supports the D2D function;

Select a cell that supports the D2D function and meets the appropriate cell conditions to camp on, and set the frequency point of the cell to the highest priority.

34. The UE according to claim 31, characterized in that when the D2D functional unit is turned on to enable the D2D cell reselection function, the cell selection unit is specifically used to:

According to the notification sent by the eNB whether the cell served by the eNB supports the D2D function, only the searched D2D cells are reselected; Or, if the serving cell or neighboring cell is a D2D cell, the cell is selected to camp on the D2D cell based on the notification sent by the eNB of whether the cell served by the eNB supports the D2D function and the D2D parameters sent by the eNB.

35. The UE according to claim 34, wherein the D2D parameters include cell reselection parameters.

36. The UE according to claim 35, wherein the D2D parameters further include a hysteresis value for the serving cell.

37. The UE according to claim 35 or 36, characterized in that, for a neighboring cell that supports the D2D function, the D2D parameters further include an offset value during cell reselection of the neighboring cell.

38. The UE according to claim 31, characterized in that the support for D2D function specifically includes proximity service discovery capability and/or proximity service communication capability, then:

For a UE that only has the Proximity Service Discovery capability, when the current resident cell does not support the Proximity Service Discovery function, the D2D functional unit turns on the D2D cell selection function or the D2D cell reselection function; Notification of whether the cell supports D2D function, select the D2D cell that supports the proximity service discovery function to camp the UE;

For a UE that only has ProSe communication capability, when the current resident cell does not support ProSe communication function, the D2D functional unit turns on the D2D cell selection function or the D2D cell reselection function; Notification of whether the cell supports D2D function, choose to camp the UE in a D2D cell that supports proximity service communication function, and then turn off the D2D cell selection function;

A UE that has both proximity service discovery capabilities and proximity service communication capabilities, when the current resident cell does not support the proximity service discovery function or the proximity service communication function, turns on the D2D functional unit to turn on the D2D cell selection function or the D2D cell reselection function; Cell The selection unit selects to camp the UE in a D2D cell that supports the ProSe discovery function or a D2D cell that supports the ProSe communication function based on the notification sent by the eNB as to whether the cell served by the eNB supports the D2D function, and then turns off the D2D cell selection function. .

39. The UE according to claim 31, characterized in that, the UE further includes: The reporting unit is used to report whether the UE supports the D2D function when reporting the UE capability.

40. The UE according to claim 39, wherein the reporting unit is further configured to perform at least one of the following steps:

If the UE sets the D2D function to the highest priority, the eNB is notified through the RRC message that the UE sets the D2D function to the highest priority;

When the UE cancels setting the D2D function as the highest priority, it notifies the eNB through the RRC message that the UE cancels setting the D2D function as the highest priority;

After cell handover, if the UE does not report that it has set the D2D function to the highest priority before the cell handover, the eNB of the cell where it is currently camping will be notified through the RRC message that the UE has set the D2D function to the highest priority.