CN113873584B

CN113873584B - Cell switching method and communication device

Info

Publication number: CN113873584B
Application number: CN202010619952.7A
Authority: CN
Inventors: 王晓峰
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2020-06-30
Filing date: 2020-06-30
Publication date: 2023-04-07
Anticipated expiration: 2040-06-30
Also published as: CN113873584A

Abstract

The invention provides a cell switching method and a communication device, which are used for solving the problem of service interruption of the existing user. The method comprises the following steps: when executing cell switching judgment aiming at terminal equipment, a source base station determines a candidate switching cell list according to cell switching conditions, wherein the candidate switching cell list comprises N adjacent cells; selecting a target cell from N adjacent cells according to the load levels of the N adjacent cells, wherein the load level of each adjacent cell is used for representing the load state of the cell; and sending a switching request to a target base station for managing the target cell, wherein the switching request is used for indicating the terminal equipment to be switched from the source cell to the target cell. By the method, the source base station selects the target cell according to the load state of the adjacent cell, so that the problem that the target cell cannot access the terminal equipment due to heavy load, and the service of the terminal equipment is interrupted is avoided.

Description

Cell switching method and communication device

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a cell switching method and a communications apparatus.

Background

Due to the mobility of the terminal Equipment (UE), the terminal Equipment is handed over between different base stations. When the source base station performs the handover decision of the target cell, it will send a handover request to the target cell based on the cell signal strength and other information included in the measurement report reported by the terminal device.

However, the target cell may not access the terminal device, so that the target base station to which the target cell belongs sends a handover failure response to the source base station, thereby causing interruption of the user service of the terminal device.

Disclosure of Invention

The invention provides a cell switching method and a communication device, which are used for solving the problem of service interruption of the existing user.

In a first aspect, an embodiment of the present invention provides a cell handover method, including:

when executing cell switching judgment aiming at terminal equipment, a source base station determines a candidate switching cell list according to cell switching conditions, wherein the candidate switching cell list comprises N adjacent cells, and N is a positive integer; selecting a target cell from N adjacent cells according to the load levels of the N adjacent cells, wherein the load level of each adjacent cell is used for representing the load state of the cell; and then sending a switching request to a target base station managing the target cell, wherein the switching request is used for indicating the terminal equipment to be switched from the source cell to the target cell.

By the method, the source base station selects the target cell according to the load state of the adjacent cell, so that the problem that the target cell cannot access the terminal equipment due to heavy load, and the service of the terminal equipment is interrupted is avoided.

In one possible embodiment, the method may further include: and the source base station receives a first message sent by the target base station, wherein the first message carries first load information, and the first load information comprises the load grade of the target cell.

In the method, the target base station sends the load level of the target cell to the source base station, so that the source base station can make selection according to the load level of the target cell.

In a possible implementation, the first message may be a configuration update response message or a configuration update request message. And when the target base station determines that the load level of the target cell changes, the changed load level of the target cell is sent to the source base station through a configuration update request message or a configuration update response message. When the target base station determines that the target cell is added to the managed cells, the target base station sends the load level of the target cell to the source base station through a configuration update request message or a configuration update response message.

In a possible implementation manner, the first message is an XN establishment request message, the first load information includes a load level of a cell managed by the target base station, and the cell managed by the target base station includes the target cell; the method further comprises the following steps: and the source base station sends an XN establishment response message to the target base station, wherein the XN establishment response message carries second load information, and the second load information comprises the load grade of the cell managed by the source base station.

In the method, in the message interaction process of establishing the XN communication between the source base station and the target base station, the load levels of the cells managed by the two sides are interacted, and through the mode, the source base station can know the load level of each adjacent cell.

In a possible implementation manner, the first message is an XN setup response message, the first load information includes a load level of a cell managed by the target base station, and the cell managed by the target base station includes the target cell; the method further comprises the following steps: before the source base station receives the first message sent by the target base station, the source base station sends an XN establishment request message to the target base station, wherein the XN establishment request message carries second load information, and the second load information comprises the load level of a cell managed by the source base station. In the method, the load levels of the cells managed by the two parties are interacted in the message interaction process of establishing the XN communication between the source base station and the target base station, and through the mode, the source base station can know the load levels of all the adjacent cells.

In a possible implementation manner, the selecting, by the source base station, a target cell from N neighboring cells according to load levels of the N neighboring cells includes:

when the load grade is in direct proportion to the load occupancy rate, the source base station selects an adjacent cell with the lowest load grade from the N adjacent cells as the target cell; alternatively, the first and second liquid crystal display panels may be,

when the load grade is inversely proportional to the load occupancy rate, the source base station selects the neighbor cell with the highest load grade from the N neighbor cells as the target cell.

In the method, the adjacent cell with the minimum load occupancy rate is selected as the target cell, so that the switching success rate is improved.

In a possible embodiment, the method may further include: when the N adjacent cells are overload cells, determining that the switching process is ended according to a configuration strategy;

when the load grade is in direct proportion to the load occupancy rate, the load grade of the overload cell is the highest grade in the configured load grades; and when the load grade is in inverse proportion to the load occupancy rate, the load grade of the overload cell is the lowest grade in the configured load grades.

In the method, the N adjacent cells are overload cells, and the switching process can be ended according to the configuration strategy because the switching success rate is low, so that the resource waste caused by the switching failure can be reduced.

In a possible implementation manner, when the load level is proportional to the load occupancy rate, and a task currently executed by the terminal device includes a new air interface voice VONR service, the source base station selects a target cell from N neighboring cells according to the load levels of the N neighboring cells, including:

when the N adjacent cells comprise M adjacent cells supporting VONR services, determining adjacent cells with the load level less than or equal to a first threshold value from the M adjacent cells supporting the VONR services, and selecting the adjacent cell with the lowest load level from the adjacent cells with the load level less than or equal to the first threshold value as a target cell; alternatively, the first and second electrodes may be,

when the load levels of M adjacent cells supporting VONR services included in the N adjacent cells are all larger than a first threshold value, selecting the adjacent cell with the lowest load level from the M adjacent cells supporting VONR services as the target cell; alternatively, the first and second electrodes may be,

when the load levels of M adjacent cells which support the VONR service and are included in the N adjacent cells are all larger than a first threshold value, selecting an adjacent cell with the lowest load level from the adjacent cells which do not support the VONR service and are included in the N adjacent cells as the target cell.

Wherein M is a positive integer less than N.

In the above embodiment, the selection is preferentially made from the neighboring cell supporting the VONR service with a lower load occupancy range, which can improve the success rate of handover and reduce the risk of service interruption.

In one possible embodiment, the method may further include: and when the N adjacent cells are all overloaded cells, the load grade of the overloaded cell is the highest grade in the configured load grades, and the switching process is determined to be finished according to the configuration strategy.

In a second aspect, an embodiment of the present invention provides a cell handover method, including: a first base station sends a first request message to a second base station, wherein the first request message carries the load level of a cell managed by the first base station; the first base station receives a first request response from a second base station, wherein the first request response carries the load level of a cell managed by the second base station; wherein the load level of each cell characterizes the load status of the cell and is used for cell handover.

In the method, the load grades of the cells managed by the two sides are interacted in the message interaction process of establishing the XN communication between the first base station and the second base station, and by the mode, the source base station can know the load grades of the adjacent cells when executing the switching and further execute the cell switching according to the load grades.

In a possible implementation manner, the first request message is an XN setup request message, and the first response message is an XN setup response message.

In one possible embodiment, the method further comprises: and when the first base station determines that the load level of a first cell in the cells managed by the first base station changes, sending a second request message to the second base station, wherein the second request message carries the updated load level of the first cell.

In the above embodiment, when the load level of a cell in the base station changes, the changed load level of the cell is timely sent to the base station that has established the XN connection, so that other base stations can update the load levels of neighboring cells in time, and the handover success rate is improved.

In one possible embodiment, the method further comprises: when the first base station determines that the cell managed by the first base station increases a second cell, the first base station sends a second request message to the second base station, wherein the second request message carries the increased load level of the second cell.

In the above embodiment, when a cell is added to a base station, the added load level of the cell is timely sent to the base station that has established the XN connection, so that other base stations can update the load level of the neighboring cell in time, and the handover success rate is improved.

In a possible implementation, the second request message is a node configuration update message.

In a third aspect, an embodiment of the present invention provides a communication apparatus, applied to a source base station, including:

the processing unit is used for determining a candidate switching cell list according to cell switching conditions when cell switching judgment aiming at the terminal equipment is executed, wherein the candidate switching cell list comprises N adjacent cells N which are positive integers;

the processing unit is further configured to select a target cell from the N neighboring cells according to load levels of the N neighboring cells, where the load level of each neighboring cell is used to characterize a load state of the cell;

a transceiver unit, configured to send a handover request to a target base station that manages the target cell, where the handover request is used to instruct the terminal device to handover from the source cell to the target cell.

In a fourth aspect, an embodiment of the present invention provides a communication apparatus, applied to a first base station, including:

a sending unit, configured to send a first request message to a second base station, where the first request message carries a load level of a cell managed by a first base station;

a receiving unit, configured to receive a first request response from a second base station, where the first request response carries a load level of a cell managed by the second base station;

wherein the load level of each cell characterizes the load status of the cell and is used for cell handover.

In a fifth aspect, an embodiment of the present invention provides a communication apparatus, which may be applied to a base station, such as a source base station, and includes a memory and a processor;

a memory for storing program instructions;

a processor, configured to invoke the program instructions stored in the memory, and execute the method performed by the source base station in any implementation manner of the first aspect according to the obtained program.

In a sixth aspect, an embodiment of the present invention provides a communication apparatus, where the apparatus may be applied to a terminal device, where the apparatus includes a memory and a processor;

a memory for storing program instructions;

and the processor is used for calling the program instructions stored in the memory and executing the method of any implementation mode of the second aspect according to the obtained program.

In a seventh aspect, an embodiment of the present invention provides a computer-readable storage medium, which stores computer instructions, and when the computer instructions are executed on a computer, the computer is caused to execute the above method.

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

Drawings

Fig. 1 is a schematic structural diagram of a communication system according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of another communication system according to an embodiment of the present invention;

fig. 3 is a handover flowchart according to an embodiment of the present invention;

fig. 4 is a schematic diagram of another handover procedure according to an embodiment of the present invention;

fig. 5 is a schematic flow chart of a cell switching method according to an embodiment of the present invention;

fig. 6 is a schematic flow chart of another cell handover method according to an embodiment of the present invention;

fig. 7 is a flowchart illustrating another cell handover method according to an embodiment of the present invention;

fig. 8 is a diagram of a communication device 800 according to an embodiment of the invention;

fig. 9 is a schematic diagram of a communication device 900 according to an embodiment of the present invention.

Detailed Description

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.

The application scenario described in the embodiment of the present invention is for more clearly illustrating the technical solution of the embodiment of the present invention, and does not form a limitation on the technical solution provided in the embodiment of the present invention, and it can be known by a person skilled in the art that with the occurrence of a new application scenario, the technical solution provided in the embodiment of the present invention is also applicable to similar technical problems. In the description of the present invention, the term "plurality" means two or more unless otherwise specified.

Fig. 1 illustrates a communication system architecture, it should be understood that the embodiments of the present invention are not limited to the system shown in fig. 1, and moreover, the apparatus in fig. 1 may be hardware, or may be a functionally divided software, or a combination of the two. As shown in fig. 1, a system architecture provided in the embodiment of the present invention includes a first base station and a second base station. The communication system may further comprise a terminal device and core network elements (not shown in fig. 1), etc. For example, the terminal device may perform handover between the first base station and the second base station during moving. When the terminal equipment is switched from the first base station to the second base station, the first base station is a source base station, and the second base station is a target base station. When the terminal equipment is switched from the second base station to the first base station, the first base station is a target base station, and the second base station is a source base station. It should be noted that, in the embodiment of the present invention, the number of base stations included in the communication system and the number of terminal devices are not limited.

A Terminal device (UE), also called a Terminal device, a Terminal, a Mobile Station (MS), a Mobile Terminal (MT), etc., is a device that provides voice and/or data connectivity to a User, for example, a handheld device, a vehicle-mounted device, etc. with a wireless connection function. Currently, some examples of terminals are: a Mobile phone (Mobile phone), a tablet computer, a notebook computer, a palm computer, a Mobile Internet Device (MID), a wearable Device, a Virtual Reality (VR) Device, an Augmented Reality (AR) Device, a wireless terminal in Industrial Control (Industrial Control), a wireless terminal in unmanned driving (self driving), a wireless terminal in remote surgery (remote medical supply), a wireless terminal in smart grid (smart grid), a wireless terminal in transportation safety, a wireless terminal in city (smart city), a wireless terminal in smart home (smart home), and the like.

The base station (including the first base station and the second base station) related in the embodiment of the present invention may also be referred to as AN Access Node (Access Node, or AN for short) to provide a wireless Access service for the terminal. The Base Station may be a Base Transceiver Station (BTS) in a Global System for Mobile communication (GSM) System or a Code Division Multiple Access (CDMA) System, a Base Station (NodeB) in a Wideband Code Division Multiple Access (WCDMA) System, a small Base Station device, a wireless Access Node (WiFi AP), a wireless interworking Microwave Access Base Station (WiMAX BS), and the like, and may also be an evolved Node B (eNB or eNodeB) in an LTE System, a Base Station device in a 5G network or a New Radio (NR) network, or a Base Station device in a future network, which is not limited by the present invention.

Illustratively, the core network device may include an Access and Mobility Management entity (AMF), a Session Management Function (SMF), and the like.

Referring to fig. 2, a schematic diagram of a handover process is shown. The XN source base station (source NG-RAN node) determines a target cell to be switched based on information such as cell signal strength, mobility limitation and the like in a measurement report reported by the terminal equipment, and then sends a switching request message (handover request) to the target base station (target NR-RAN node). And the target cell of the target base station performs resource allocation according to the handover request message, for example, allocates radio resources and transmission link resources, and returns a handover request acknowledgement (handover request acknowledgement) to the source base station.

If the target base station determines that the resource allocation result is: receiving a partial Protocol Data Unit (PDU) SESSION (SESSION), not receiving a partial PDU SESSION, or receiving a Quality of Service (QoS) stream of the PDU SESSION, not receiving a QoS stream of the PDU SESSION, for example, when a cell does not support NR voice Service (voice of NR, VONR), then a QoS stream of 5qi =1 cannot be received, and then the target base station carries a resource allocation result in a HANDOVER REQUEST acknowledgement message to the source base station. Wherein, 5qi =1 indicates that the voice service is VONR.

If the target cell of the target base station determines that all PDU SESSIONs are not accepted, or the cell is overloaded, or the terminal device cannot be accepted due to other reasons, the target base station returns a handover preparation failure (handover failure) to the source base station, as shown in fig. 3.

As can be seen from the above, the information about whether the base station is under a heavy load/overload condition cannot be timely notified to the neighboring base stations, and whether the target cell supports the VONR service cannot be known by the source base station. Therefore, when the source base station performs handover decision of the target cell, and sends a handover request for cell signal strength and mobility restriction of the measurement report, the source base station cannot know whether the target cell is overloaded and cannot access the UE, or the UE has VONR service but does not know whether the target cell supports information such as VONR service, and thus, the source base station blindly sends a handover message, which causes a failure of return due to overload when the target cell performs resource allocation. Because the VONR service is not supported, qoS for 5qi =1 cannot be accepted, so that the voice service of the user is lost, and the success rate and efficiency of handover are affected.

Based on this, embodiments of the present application provide a cell handover method and a communication apparatus, which are used to improve a handover success rate and efficiency. The scheme provided by the embodiment of the invention is described in detail in the following with reference to the accompanying drawings.

Referring to fig. 4, a cell handover method provided in an embodiment of the present invention is described with reference to interaction between a first base station and a second base station. The first base station is a neighbor base station of the second base station. The first base station establishes an XN connection with the second base station. It should be noted that, the following method can be adopted between adjacent base stations in the communication system to interact the load levels of the cells managed by both parties.

S401, a first base station sends a first request message to a second base station, wherein the first request message carries the load level of a cell managed by the first base station.

After receiving the first request message, the second base station may include the load level of each cell in the neighbor cell list. The second base station sends a first request response to the first base station.

S402, the first base station receives a first request response from a second base station, and the first request response carries the load level of the cell managed by the second base station.

Wherein, the load grade of a cell is used for representing the load state of the cell; the load level of the cell is used for cell handover.

Illustratively, the first request message may be an XN setup request message, and the first response message is an XN setup response message. That is, the load levels of the cells managed by the first base station and the second base station are interacted in the process of establishing connection between the first base station and the second base station. For example, referring to fig. 5, the first base station is an NG-RAN node (node) 1 as an example, and the second base station is an NG-RAN node2 as an example. The NG-RAN node 1 sends an XN setup request message to the NG-RAN node 2. The Xn setup request message may include NR serving Cell Information 1 (Served Cell Information NR 1). The Served Cell Information NR carries load Status (load Status) Information, i.e., a load class, of the Cell managed by the NG-RAN node 1. The NG-RAN node2 replies an XN setup response message to the NG-RAN node 1. The Xn set-up response message includes the Served Cell Information NR2. The Served Cell Information NR2 carries load Status Information, i.e., load level, of the Cell managed by the NG-RAN node 2.

The load level may include a plurality of, such as different load levels corresponding to different load occupancy ranges. As an example, the load level may include 3 levels, such as normal load, heavy load, and overload. The normal load occupancy rate of the load is less than A1, the heavy load occupancy rate is greater than or equal to A1 and less than A2, and the overload load occupancy rate is greater than A2. As another example, the load levels may also include 4 levels, such as light load, normal load, heavy load, and overload.

It should be noted that, in the embodiment of the present invention, different load levels from high to low correspond to different load occupancy ranges. For example, the load level is inversely proportional to the load occupancy rate, or the load level is directly proportional to the load occupancy rate. Taking 3 grades as an example, the load occupancy rate corresponding to the normal load is less than a first threshold value; the load occupancy rate corresponding to the heavy load is greater than or equal to a first threshold value and less than a second threshold value, and the load occupancy rate corresponding to the overload is greater than or equal to the second threshold value.

In a possible implementation manner, when determining that the load level of a first cell in the cells managed by the first base station changes, the first base station sends a second request message to the second base station, where the second request message carries the updated load level of the first cell.

In a possible implementation manner, when the first base station determines that the cell managed by the first base station increases a second cell, the first base station sends a second request message to the second base station, where the second request message carries the increased load level of the second cell. Illustratively, the second request message may be a node configuration update (configure update) message.

As an example, see fig. 6, which still takes NG-RAN node (node) 1 and NG-RAN node2 as an example. If there is a change in the Load Status information of NG-RAN NODE 1, an NG-RAN NODE CONFIGURATION UPDATE request message is sent to NG-RAN NODE 2. The service Cells To modification NR- > service Cell Information NR comprised by the NG-RAN node configuration update (i.e., in the service Cells To modification NR Information of the service Cell Information NR) carries the Load Status Information of the modified Cell of the NG-RAN node 1. If a new Cell is activated in the NG-RAN node 1, the Load Status Information of the new Cell is added in the Served Cells NR To Add- > Served Cell Information NR (i.e. the Served Cells NR To Add Information of the Served Cell Information NR).

The NG-RAN NODE2 replies an NG-RAN NODE CONFIGURATION UPDATE ACKNOWLEDGE message to the NG-RAN NODE 1. If the Load level of the Cell of the NG-RAN node2 changes, the Served Cell Information NR included in the NG-RAN node configuration update response carries the Load Status Information of the corresponding Cell of the NG-RAN node 2. If a new Cell is activated in the NG-RAN node2, the NG-RAN node configuration update response includes a Served Cell Information NR that adds Load Status Information of the new Cell of the NG-RAN node 2.

Part of Information contained in the Served Cell Information NR is exemplarily described as follows, see table 1.

TABLE 1

After the load grades of the cells of the two adjacent base stations in the communication system are interacted in the mode, if one base station is used as a source base station, when switching judgment is carried out, except for the judgment of a measurement report result and mobility limitation, the load grade obtained by the Xn interface is referred to for selecting a switching target cell. In addition, the user of the terminal device may have the VONR service, and when selecting the target cell, further refers to whether the neighboring cell has the capability of the VONR service.

In the embodiment of the present invention, whether a cell supports the VONR service or not, or whether the cell has the capability of the VONR service, may be used as a planning parameter, and there may be two values, such as support and non-support. When the operation maintenance management device issues the configuration data to the base station, the VONR service support capability of the neighboring cell may be configured in the neighboring cell parameter table. If the VONR service support capability of the cell is modified, the operation maintenance management equipment updates the modified VONR service support capability of the cell to the base station by configuring a data updating process, so that the base station can use the VONR service support capability of the cell as a selection reference of a handover target cell.

The above switching process is explained below with reference to fig. 7.

S701, when a source base station executes cell switching judgment aiming at terminal equipment, a candidate switching cell list is determined according to cell switching conditions, and the candidate switching cell list comprises N adjacent cells. N is a positive integer. The source base station and the target base station are two base stations, such as a first base station and a second base station, respectively, in the communication system, which have established an XN connection. For example, the source base station is a first base station and the target base station is a second base station, or the source base station is the second base station and the target base station is the first base station.

For example, the condition that the N neighboring cells satisfy the cell handover condition may be that the signal strength of the cell reaches a threshold, the mobility limit of the terminal device is satisfied, and the like.

S702, the source base station selects a target cell from N adjacent cells according to the load grades of the N adjacent cells, wherein the load grade of each adjacent cell is used for representing the load state of the cell.

S703, the source base station sends a handover request to a target base station managing the target cell, where the handover request is used to instruct the terminal device to handover from the source cell to the target cell.

In one possible embodiment, the source base station may obtain the load level of the neighboring cell in the manner of fig. 4, fig. 5 or fig. 6.

For the load level of the target cell of the target base station, the source base station may acquire the load level by the following method:

and the source base station receives a first message sent by the target base station, wherein the first message carries first load information, and the first load information comprises the load grade of the target cell.

For example, the target base station may send the load level of the target cell to the source base station when establishing the XN connection with the source base station. Taking the target base station as the initiator of the XN connection as an example, the first message is an XN establishment request message, the first load information includes a load level of a cell managed by the target base station, and the cell managed by the target base station includes the target cell; and the source base station sends an XN establishment response message to the target base station, wherein the XN establishment response message carries second load information, and the second load information comprises the load grade of the cell managed by the source base station.

For another example, taking the source base station as the initiator of the XN connection: the first message is an XN establishment response message, the first load information comprises the load level of a cell managed by the target base station, and the cell managed by the target base station comprises the target cell; before the source base station receives the first message sent by the target base station, the source base station sends an XN establishment request message to the target base station, wherein the XN establishment request message carries second load information, and the second load information comprises the load level of a cell managed by the source base station.

For another example, the first message is a configuration update response message or a configuration update request message. For example, the load level of the target cell is updated, and the target base station sends the updated load level of the target cell to the source base station through a configuration update response message or a configuration update request message. For example, the target cell is a newly added cell in the target base station, and the target base station sends the load level of the newly added target cell to the source base station through a configuration update response message or a configuration update request message.

In a possible implementation manner, the source base station selects a target cell from N neighboring cells according to load levels of the N neighboring cells, where different load levels correspond to different load occupancy ranges, and the method may be implemented by any one of the following manners:

in a first mode, when the load level is proportional to the load occupancy rate, the source base station selects an adjacent cell with the lowest load level from the N adjacent cells as the target cell.

For example, taking the load grade as three grades, grade 1, the load is normal; grade 2, heavy load; class 3, overload. Level 3 is higher than level 2 and level 2 is higher than level 1.

And the source cell preferentially selects the neighbor cell with normal load as the target cell. When the N adjacent cells do not include the adjacent cell with normal load, the cell with heavy load is selected as the target cell.

If the N adjacent cells are overload cells, selecting the overload cell as a target cell in one mode, and triggering the switching process to end in the other mode. A local configuration policy for the overloaded cell may be configured in the source base station, where the local configuration policy is an attempt to perform handover or a handover failure. If the local configuration strategy is to try to switch, the source base station initiates a switch request aiming at the overloaded cells. If the local configuration strategy is the switching failure, the switching judgment is finished.

It should be noted that, the priorities of the N neighboring cells may be different, and when the target cell is selected to determine the load level, the target cell may be selected according to the priority order of the priorities.

And in a second mode, when the load grade is in inverse proportion to the load occupancy rate, the source base station selects the adjacent cell with the highest load grade from the N adjacent cells as the target cell.

It should be noted that, when the load level is directly proportional to the load occupancy rate, the load level of the overloaded cell is the highest level in the configured load levels; when the load level is inversely proportional to the load occupancy rate, the load level of the overloaded cell is the lowest level of the configured load levels.

The above method for selecting the target cell may be applied to a terminal device that does not support the VONR service or a terminal device that does not include the VONR service in the currently executed service.

In a possible implementation manner, when the task currently executed by the terminal device includes a new voice over air interface VONR service, the source base station selects a target cell from N neighboring cells according to load levels of the N neighboring cells, which may be implemented as follows:

different load grades correspond to different load occupancy ranges, and in the case that the load grades are proportional to the load occupancy:

when the N neighboring cells include M neighboring cells supporting the VONR service, determining a neighboring cell with a load level less than or equal to a first threshold from the M neighboring cells supporting the VONR service, and then selecting a neighboring cell with a lowest load level from the cells with the load level or the neighboring cells equal to the first threshold as the target cell.

For example, taking four load levels as an example, level 1, the load is light; grade 2, normal load; grade 3, heavy load; class 4, overload. Level 4 is higher than level 3, level 3 is higher than level 2, and level 2 is higher than level 1. For example, the first threshold is level 2. That is, the N neighboring cells include M neighboring cells supporting the VONR service, and a neighboring cell with a light load is preferentially selected from the M neighboring cells supporting the VONR service as a target cell. When the M adjacent cells supporting the VONR service do not comprise adjacent cells with light load, selecting the adjacent cells with normal load from the M adjacent cells supporting the VONR service as target cells.

When the load levels of M neighboring cells supporting the VONR service included in the N neighboring cells are all greater than a first threshold, one way is:

and selecting the neighbor cell with the lowest load level from the M neighbor cells supporting the VONR service as the target cell. Following the above example, the load levels of the M neighboring cells supporting the VONR service are all greater than level 2, that is, the M neighboring cells supporting the VONR service include heavily loaded and/or overloaded cells. The neighbor cell with light load can be preferentially selected from the neighbor cells which do not support the VONR service as the target cell, and if the neighbor cells which do not support the VONR service do not include the neighbor cells with light load, the neighbor cells with normal load can be selected from the neighbor cells which do not support the VONR service as the target cell.

Further, if the neighbor cells which do not support the VONR service do not include neighbor cells with light and normal loads, the neighbor cell with heavy load may be preferentially selected from the neighbor cells which support the VONR service as the target cell. If all the N adjacent cells are overloaded cells, the overloaded cells can be selected as target cells, or the switching process is directly triggered to end. A local configuration policy for the overloaded cell may be configured in the source base station, where the local configuration policy is an attempt to perform handover or a handover failure. If the local configuration strategy is to try to switch, the source base station initiates a switch request aiming at the overloaded cells. If the local configuration strategy is the switching failure, the switching judgment is finished.

The other mode is as follows:

when the load levels of M adjacent cells which support the VONR service and are included in the N adjacent cells are all larger than a first threshold value, selecting an adjacent cell with the lowest load level from the adjacent cells which do not support the VONR service and are included in the N adjacent cells as the target cell. Following the above example, the load levels of the M neighboring cells supporting the VONR service are all greater than level 2, that is, the M neighboring cells supporting the VONR service include heavily loaded and/or overloaded cells. A heavily loaded neighbor cell may be preferentially selected as a target cell from among neighbor cells supporting the VONR service. Further, if the neighboring cells supporting the VONR service do not include neighboring cells with light load, normal load, and heavy load, the neighboring cell with the lowest load level may be preferentially selected from the neighboring cells not supporting the VONR service as the target cell. If all the N adjacent cells are overloaded cells, the overloaded cells can be selected as target cells, or the switching process is directly triggered to end. A local configuration policy for the overloaded cell may be configured in the source base station, where the local configuration policy is an attempt to perform handover or a handover failure. If the local configuration strategy is to try to switch, the source base station initiates a switch request aiming at the overloaded cells. If the local configuration strategy is the switching failure, the switching judgment is finished.

As an example, taking the load level as 3 levels, level 1, the load is normal; grade 2, heavy load; class 3, overload. Level 3 is higher than level 2 and level 2 is higher than level 1. For example, the first threshold is level 2. The source base station may determine a candidate handover cell list (including N neighbor cells) from high to low based on the priority according to the measurement report and the mobility restriction decision condition. M adjacent cells supporting VONR are screened out first, and the load grade of the corresponding cell is the adjacent cell with normal load. And if the neighbor cells with normal load exist, initiating a switching request aiming at the cells with normal load as target cells.

If the M neighboring cells supporting the VONR do not include the neighboring cell with normal load, a neighboring cell with heavy load may be preferentially selected from the M neighboring cells supporting the VONR or a neighboring cell with normal load in the neighboring cells not supporting the VONR may be preferentially selected as the target cell for handover according to a locally configured preference policy.

For example, the preferred strategy is to preferentially select a heavy-load neighbor cell from M neighbor cells supporting VONR as a target cell, and if all the M neighbor cells supporting VONR are overloaded cells, a handover may be further performed from a neighbor cell which does not support VONR and has a normal load as a target cell. If the neighbor cells with normal load are not included in the non-supported VONR neighbor cells, the neighbor cell with heavy load can be selected as the target cell from the non-supported VONR neighbor cells.

For another example, the preferred strategy is to preferentially select a neighboring cell not supporting the VONR with normal load as the target cell for handover, and if the neighboring cell not supporting the VONR with normal load does not include a neighboring cell supporting the VONR with normal load, the neighboring cell with heavy load may be further selected from the M neighboring cells supporting the VONR as the target cell for handover. If M adjacent cells supporting the VONR are overloaded cells, a heavily loaded adjacent cell can be selected as a target cell from the adjacent cells not supporting the VONR. If all the N adjacent cells are overloaded cells, the overloaded cells can be selected as target cells, or the switching process is directly triggered to end. The source base station may be configured with a local configuration policy for the overloaded cell, where the local configuration policy is an attempt to perform handover or a handover failure. If the local configuration policy is to attempt handover, the source base station is directed to these overloaded cells.

And under the condition that the load grade is inversely proportional to the load occupancy rate:

when the N adjacent cells comprise M adjacent cells supporting VONR services, determining an adjacent cell with the load level larger than or equal to a second threshold value from the M adjacent cells supporting the VONR services, and selecting an adjacent cell with the highest load level as the target cell from the adjacent cells with the load level larger than or equal to the second threshold value; alternatively, the first and second liquid crystal display panels may be,

when the load levels of M adjacent cells supporting VONR service, which are included in the N adjacent cells, are all smaller than a second threshold value, selecting the adjacent cell with the highest load level from the M adjacent cells supporting VONR service as the target cell; alternatively, the first and second liquid crystal display panels may be,

and when the load levels of M adjacent cells which support the VONR service and are included in the N adjacent cells are all smaller than a second threshold value, selecting the adjacent cell with the highest load level from the adjacent cells which do not support the VONR service and are included in the N adjacent cells as the target cell.

And when the N adjacent cells are all overloaded cells, the load grade of the overloaded cell is the lowest grade in the configured load grades, and the switching process is determined to be finished according to the configuration strategy.

For example, the load level is four levels, level 4, the load is light; grade 3, normal load; grade 2, heavy load; class 1, overload. Level 4 is higher than level 3, level 3 is higher than level 2, and level 2 is higher than level 1. For example, the second threshold is level 3. For another example, if the load grade is 3 grades, the load is normal, grade 3; grade 2, heavy load; class 1, overload. Level 3 is higher than level 2 and level 2 is higher than level 1. For example, the second threshold is level 3.

Based on the same inventive concept as the method described above, the embodiment of the present invention further provides a communication apparatus 800, which is applied to a base station, such as a source base station, for example, the communication apparatus 800 may be a chip or a chip system in the base station, or one or more processors. Referring to fig. 8, the communication device 800 includes a processing unit 801 and a transceiver unit 802. The transceiver 802 may include a transmitter 802A and a receiver 802B, where the transmitter 802A is responsible for transmitting signals and the receiver 802B is responsible for receiving signals, and the transceiver 802 may be implemented by a module and is responsible for both transmitting and receiving signals.

In one possible application scenario:

a processing unit 801, configured to determine a candidate handover cell list according to a cell handover condition when performing a cell handover decision for a terminal device, where the candidate handover cell list includes N neighboring cells, and N is a positive integer;

the processing unit 801 is further configured to select a target cell from N neighboring cells according to load levels of the N neighboring cells, where a load level of one cell is used to characterize a load state of the cell;

a transceiving unit 802, configured to send a handover request to a target base station that manages the target cell, where the handover request is used to instruct the terminal device to handover from the source cell to the target cell.

In a possible implementation manner, the transceiver unit 802 is further configured to receive a first message sent by the target base station, where the first message carries first load information, and the first load information includes a load level of the target cell.

In a possible implementation manner, the first message is an XN establishment request message, the first load information includes a load level of a cell managed by the target base station, and the cell managed by the target base station includes the target cell;

the transceiver unit 802 is further configured to send an XN setup response message to the target base station, where the XN setup response message carries second load information, and the second load information includes a load level of a cell managed by the source base station.

In a possible implementation manner, the first message is an XN setup response message, the first load information includes a load level of a cell managed by the target base station, and the cell managed by the target base station includes the target cell;

the transceiver unit 802 is further configured to send, by the source base station, an XN establishment request message to the target base station before receiving the first message sent by the target base station, where the XN establishment request message carries second load information, and the second load information includes a load level of a cell managed by the source base station.

In a possible implementation manner, the first message is a configuration update response message or a configuration update request message.

In a possible implementation manner, different load levels correspond to different load occupancy ranges, and the processing unit 801 is specifically configured to:

when the load grade is in direct proportion to the load occupancy rate, selecting a neighbor cell with the lowest load grade from the N neighbor cells as the target cell; alternatively, the first and second electrodes may be,

and when the load grade is inversely proportional to the load occupancy rate, selecting the neighbor cell with the highest load grade from the N neighbor cells as the target cell.

In a possible implementation, the processing unit 801 is further configured to:

and when the adjacent cell with the lowest load grade is the overload cell, determining that the switching process is ended according to a configuration strategy.

In a possible implementation manner, different load levels correspond to different load occupancy ranges, the load levels are proportional to the load occupancy, and when a task currently executed by the terminal device includes a new air interface voice VONR service, the processing unit 801 is specifically configured to:

when the N adjacent cells comprise M adjacent cells supporting VONR services, determining adjacent cells with the load level less than or equal to a first threshold value from the M adjacent cells supporting the VONR services, and selecting the adjacent cell with the lowest load level from the adjacent cells with the load level less than or equal to the first threshold value as the target cell; alternatively, the first and second electrodes may be,

when the load levels of M adjacent cells supporting VONR services included in the N adjacent cells are all larger than a first threshold value, selecting the adjacent cell with the lowest load level from the M adjacent cells supporting VONR services as the target cell; alternatively, the first and second liquid crystal display panels may be,

In one possible embodiment of the method according to the invention, the processing unit 801 is further configured to:

and when the N adjacent cells are all overloaded cells, the load grade of the overloaded cell is the highest grade in the configured load grades, and the switching process is determined to be finished according to the configuration strategy.

In another possible scenario:

a sending unit 802A, configured to send a first request message to a second base station, where the first request message carries a load level of a cell managed by the first base station; the load level of the cell of the first base station is used for the second base station to perform cell handover.

A receiving unit 802B, configured to receive a first request response from a second base station, where the first request response carries a load level of a cell managed by the second base station;

the load level of one cell is used for representing the load state of the cell, and the load level of the cell of the second base station is used for the first base station to execute cell switching.

In one possible embodiment, the method further comprises:

a processing unit 801, configured to determine that a load level of a first cell of cells managed by the first base station changes;

the sending unit 802A is further configured to send a second request message to the second base station, where the second request message carries the updated load level of the first cell.

In one possible embodiment, the method further comprises:

a processing unit, configured to determine that a cell managed by the first base station increases by a second cell;

the sending unit 802A is configured to send a second request message to the second base station, where the second request message carries the increased load level of the second cell.

The division of the unit in the embodiments of the present invention is schematic, and is only a logical function division, and there may be another division manner in actual implementation, and in addition, each functional unit in each embodiment of the present invention may be integrated in one processor, may also exist alone physically, or may also be integrated in one unit by two or more units. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

Another communication apparatus 900 is provided in the embodiment of the present invention, as shown in fig. 9, including:

a communication interface 901, a memory 902, and a processor 903;

wherein, the communication apparatus 900 communicates with other devices, such as receiving and sending messages, through the communication interface 901; a memory 902 for storing program instructions; and a processor 903 for calling the program instructions stored in the memory 902 and executing the method according to the obtained program.

In the embodiment of the present invention, the specific connection medium among the communication interface 901, the memory 902, and the processor 903 is not limited, for example, a bus, and the bus may be divided into an address bus, a data bus, a control bus, and the like.

In the embodiments of the present invention, the processor may be a general purpose processor, a digital signal processor, an application specific integrated circuit, a field programmable gate array or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component, and may implement or execute the methods, steps, and logic blocks disclosed in the embodiments of the present invention. A general purpose processor may be a microprocessor or any conventional processor or the like. The steps of a method disclosed in connection with the embodiments of the present invention may be directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in the processor.

In the embodiment of the present invention, the memory may be a nonvolatile memory, such as a Hard Disk Drive (HDD) or a solid-state drive (SSD), and may also be a volatile memory, for example, a random-access memory (RAM). The memory can also be, but is not limited to, any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. The memory in embodiments of the present invention may also be circuitry or any other device capable of performing a storage function for storing program instructions and/or data.

The communication apparatus 900 may be applied to a base station, and the functions of the transceiver unit 802 and the processing unit 801 may be implemented by the processor 903. Alternatively, the functions of the transceiver unit 802 are implemented by the communication interface 901, the functions of the processing unit 801 are implemented by the processor 903, and specifically, the processor 903 is configured to call the program code in the memory 902, and implement the functions executed by the source base station or the first base station in the above-mentioned method through the communication interface 901.

Embodiments of the present invention also provide a computer-readable storage medium, which includes program code for causing a computer to perform the steps of the method provided above in the embodiments of the present invention when the program code runs on the computer.

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

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

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

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

While preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the 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 of cell handover, comprising:

when executing cell switching judgment aiming at terminal equipment, a source base station determines a candidate switching cell list according to cell switching conditions, wherein the candidate switching cell list comprises N adjacent cells, and N is a positive integer;

selecting a target cell from N adjacent cells according to the load levels of the N adjacent cells, wherein the load level of each adjacent cell is used for representing the load state of the cell;

the selecting a target cell from the N neighbor cells according to the load levels of the N neighbor cells includes:

when the load grade is in direct proportion to the load occupancy rate, the source base station selects an adjacent cell with the lowest load grade from the N adjacent cells as the target cell; alternatively, the first and second electrodes may be,

when the load grade is in inverse proportion to the load occupancy rate, the source base station selects a neighbor cell with the highest load grade from the N neighbor cells as the target cell;

and sending a switching request to a target base station managing the target cell, wherein the switching request is used for indicating the terminal equipment to be switched from a source cell to the target cell.

2. The method of claim 1, further comprising:

and receiving a first message sent by the target base station, wherein the first message carries first load information, and the first load information comprises the load grade of the target cell.

3. The method of claim 2, wherein the first message is an XN setup request message, the first load information includes a load level of a cell managed by the target base station, the cell managed by the target base station includes the target cell;

the method further comprises the following steps:

and sending an XN establishment response message to the target base station, wherein the XN establishment response message carries second load information, and the second load information comprises the load level of the cell managed by the source base station.

4. The method of claim 2, wherein the first message is an XN setup response message, the first load information includes a load level of a cell managed by the target base station, the cell managed by the target base station includes the target cell;

the method further comprises the following steps:

before receiving a first message sent by the target base station, the source base station sends an XN establishment request message to the target base station, wherein the XN establishment request message carries second load information, and the second load information comprises a load level of a cell managed by the source base station.

5. The method of any one of claims 1-4, further comprising:

when the N adjacent cells are overload cells, determining that the switching process is ended according to a configuration strategy;

when the load grade is in direct proportion to the load occupancy rate, the load grade of the overload cell is the highest grade in the configured load grades; when the load level is inversely proportional to the load occupancy rate, the load level of the overloaded cell is the lowest level of the configured load levels.

6. The method according to any one of claims 1 to 4, wherein when the load level is proportional to the load occupancy rate and the task currently performed by the terminal device includes a new voice over air (VONR) service, the source base station selects a target cell from N neighboring cells according to the load levels of the N neighboring cells, including:

7. The method of claim 6, further comprising:

8. A method of cell handover, comprising:

a first base station sends a first request message to a second base station, wherein the first request message carries the load level of a cell managed by the first base station;

receiving a first request response from a second base station, wherein the first request response carries the load level of a cell managed by the second base station;

9. The method of claim 8, wherein the first request message is an XN setup request message and the first request response message is an XN setup response message.

10. The method of claim 8, further comprising:

and when determining that the load level of a first cell in the cells managed by the first base station changes, sending a second request message to the second base station, wherein the second request message carries the updated load level of the first cell.

11. The method of claim 8, further comprising:

when determining that the cell managed by the first base station increases a second cell, sending a second request message to the second base station, where the second request message carries the increased load level of the second cell.

12. A communication apparatus, applied to a source base station, comprising:

a processing unit, configured to determine a candidate handover cell list according to a cell handover condition when performing a cell handover decision for a terminal device, where the candidate handover cell list includes N neighboring cells, and N is a positive integer;

the processing unit, when selecting a target cell from the N neighboring cells according to the load levels of the N neighboring cells, is specifically configured to:

a transceiver unit, configured to send a handover request to a target base station that manages the target cell, where the handover request is used to instruct the terminal device to handover from a source cell to the target cell.

13. A communication apparatus, applied to a first base station, comprising:

a sending unit, configured to send a first request message to a second base station, where the first request message carries a load level of a cell managed by the first base station;

wherein the load level of each neighboring cell characterizes the load status of the cell and is used for cell handover.

14. A communications apparatus, comprising:

a memory and a processor;

a memory for storing program instructions;

a processor for calling program instructions stored in said memory and executing the method of any one of claims 1 to 11 in accordance with the obtained program.

15. A computer-readable storage medium having stored thereon computer instructions which, when run on a computer, cause the computer to perform the method of any one of claims 1-11.