CN115038128A

CN115038128A - Cell switching method, device, base station and storage medium

Info

Publication number: CN115038128A
Application number: CN202110244151.1A
Authority: CN
Inventors: 尹志宁
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2021-03-05
Filing date: 2021-03-05
Publication date: 2022-09-09
Anticipated expiration: 2041-03-05
Also published as: CN115038128B

Abstract

The embodiment of the invention provides a cell switching method, a cell switching device, a base station and a storage medium, which are applied to the technical field of communication, wherein the cell switching method comprises the following steps: and acquiring the network information of the adjacent cell according to the adjacent cell list in the measurement report reported by the terminal. And determining a candidate cell list for the terminal to perform cell switching according to the obtained network information. Instructing the terminal to perform conditional handover CHO based on the determined candidate cell list. The scheme provided by the embodiment of the invention can control the number of candidate cells in the process of conditional switch.

Description

Cell switching method, device, base station and storage medium

Technical Field

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

Background

In a mobile communication network, a terminal is positioned in a cell of a base station, and network communication is realized based on the positioned cell. In an actual communication environment, the signal strength of a cell in which the terminal is located may change, or the terminal may move to a range covered by another cell, and therefore, the terminal may desire to perform cell switching to continue high-quality network communication. That is, the terminal is handed out from the source cell where it is located, and is handed over to a new target cell, and network communication is performed based on the target cell.

In the prior art, a terminal may perform cell HandOver based on a CHO (Conditional HandOver) method. In this case, the source base station of the source cell selects a preset number of candidate cells for the terminal, the terminal performs condition monitoring on the candidate cells, and when it is monitored that a target cell satisfying a preset handover condition exists in the candidate cells, the candidate cells are switched out from the source cell and are handed over to the target cell.

Since condition monitoring is required to be performed on a plurality of candidate cells by a terminal in a cell handover process based on a CHO (Chinese hamster ovary) manner, a relatively large amount of data needs to be processed in the condition monitoring process on the plurality of candidate cells, and the data processing capability of the terminal is limited, a technology for optimizing and controlling the number of candidate cells in the condition handover process on a network side is required.

Disclosure of Invention

An object of embodiments of the present invention is to provide a cell handover method, an apparatus, a base station and a storage medium, which are used to control the number of candidate cells in a conditional handover process. The specific technical scheme is as follows:

in a first aspect, an embodiment of the present invention provides a cell handover method, where the method includes:

acquiring network information of a neighbor cell according to a neighbor cell list in a measurement report reported by a terminal;

determining a candidate cell list for the terminal to perform cell switching according to the obtained network information;

instructing the terminal to perform a conditional handover, CHO, based on the determined candidate cell list.

In a second aspect, an embodiment of the present invention provides a cell switching apparatus, where the apparatus includes:

an information obtaining module, configured to obtain network information of a neighboring cell according to a neighboring cell list in a measurement report reported by a terminal;

a cell determining module, configured to determine a candidate cell list for cell handover performed by the terminal according to the obtained network information;

and the switching indication module is used for indicating the terminal to perform conditional switching (CHO) based on the determined candidate cell list.

In a third aspect, an embodiment of the present invention provides a base station, including a memory, a transceiver, a processor:

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

acquiring network information of the neighbor cell according to a neighbor cell list in a measurement report reported by a terminal;

In a fourth aspect, the present invention provides a processor-readable storage medium, which stores a computer program for causing a processor to execute the method of any one of the first aspect.

In a fifth aspect, embodiments of the present invention also provide a computer program product containing instructions, which when run on a computer, cause the computer to perform the method of any one of the first aspect.

The embodiment of the invention has the following beneficial effects:

in the cell switching scheme provided by the embodiment of the invention, the network information of the neighbor cell can be acquired according to the neighbor cell list in the measurement report reported by the terminal. And determining a candidate cell list for the terminal to perform cell switching according to the obtained network information. And instructing the terminal to perform Conditional Handover (CHO) based on the determined candidate cell list.

As can be seen from the above, the source base station does not directly determine the candidate cell list including the predetermined number of candidate cells, but determines the candidate cell list according to the network information of the neighboring cells. That is, the network information of the neighboring cell is obtained based on the measurement report reported by the terminal, the candidate cells are dynamically selected, and the candidate cell list is determined, so that the selected candidate cells can be more suitable for the terminal, and the number of the selected candidate cells also changes with the change of the network information of the neighboring cell, rather than the unchangeable selection of a preset number of candidate cells. Therefore, not only can the finally selected candidate cell be helpful for realizing cell switching of the terminal, but also unnecessary cells can be excluded from the candidate cells, and therefore, the number of candidate cells in the conditional switching process can be controlled.

Drawings

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

Fig. 1 is a schematic flow chart of a first cell handover method according to an embodiment of the present invention;

fig. 2 is a flowchart illustrating a second cell handover method according to an embodiment of the present invention;

fig. 3A is a flowchart illustrating a third cell handover method according to an embodiment of the present invention;

fig. 3B is a schematic view of an application scenario for performing cell handover based on a CHO method according to an embodiment of the present invention;

fig. 3C is a schematic flow chart illustrating a cell handover based on a CHO method according to an embodiment of the present invention;

fig. 4 is a flowchart illustrating a fourth cell handover method according to an embodiment of the present invention;

fig. 5 is a flowchart illustrating a fifth cell handover method according to an embodiment of the present invention;

fig. 6 is a flowchart illustrating a sixth cell handover method according to an embodiment of the present invention;

fig. 7 is a schematic structural diagram of a cell switching apparatus according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of a base station according to an embodiment of the present invention.

Detailed Description

The term "and/or" in the embodiments of the present invention describes an association relationship of associated objects, and indicates that three relationships may exist, for example, a and/or B may indicate: a exists alone, A and B exist simultaneously, and B exists alone. The character "/" generally indicates that the former and latter associated objects are in an "or" relationship.

The term "plurality" in the embodiments of the present invention means two or more, and other terms are similar thereto.

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of the present invention.

In the prior art, a terminal needs to perform condition monitoring on a plurality of candidate cells during a cell switching process, and needs to perform a relatively large amount of data processing during the condition monitoring on the plurality of candidate cells, but the data processing capability of the terminal is limited.

In an embodiment of the present invention, a cell handover method is provided, where the method includes:

and acquiring the network information of the adjacent cell according to the adjacent cell list in the measurement report reported by the terminal.

And determining a candidate cell list for the terminal to perform cell switching according to the obtained network information.

Instructing the terminal to perform conditional handover CHO based on the determined candidate cell list.

As can be seen from the above, the source base station does not directly determine the candidate cell list including the predetermined number of candidate cells, but determines the candidate cell list according to the network information of the neighboring cells. That is, the network information of the neighboring cell is obtained based on the measurement report reported by the terminal, the candidate cells are dynamically selected, and the candidate cell list is determined, so that the selected candidate cells can be more suitable for the terminal, the number of the selected candidate cells also changes with the change of the network information of the neighboring cell, and a preset number of candidate cells are not selected unchanged. Therefore, it is possible to make the finally selected candidate cell contribute not only to the cell handover of the terminal but also to the exclusion of unnecessary cells from the candidate cells, and thus, the number of candidate cells in the conditional handover process can be controlled.

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

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

In addition, in the embodiment of the present invention, one or more antennas may be respectively used between the base station and the terminal for Multiple Input Multiple Output (MIMO) transmission, and the MIMO transmission may be Single User MIMO (SU-MIMO) or Multi-User MIMO (MU-MIMO). The MIMO transmission may be 2D-MIMO, 3D-MIMO, FD-MIMO, or massive-MIMO, or may be diversity transmission, precoding transmission, beamforming transmission, or the like, depending on the form and number of root antenna combinations.

Referring to fig. 1, a flowchart of a first cell handover method according to an embodiment of the present invention is shown, where the method includes the following steps S101 to S103.

The executing entity of the embodiment of the present invention may be a base station, and in order to distinguish from other base stations in the following description, the base station as the executing entity is referred to as a source base station.

S101: and acquiring the network information of the adjacent cell according to the adjacent cell list in the measurement report reported by the terminal.

Specifically, the terminal monitors the network information of the neighboring cell during the working process, and reports a measurement report including a neighboring cell list and the network information of the neighboring cell to the source base station, so that the source base station obtains the network information of the neighboring cell. The network information of the neighboring cell may include signal strength, communication quality RxQual, and the like of the neighboring cell. The neighbor cell list may include a cell number, a cell name, and the like of each neighbor cell.

In addition, the terminal is in the source cell of the source base station, the number of the cells of the source base station may be one or more, and the terminal in the cell of the source base station may communicate with the source base station.

In addition, the source base station may communicate with a neighboring base station of the neighboring cell to obtain network information of the neighboring cell.

S102: and determining a candidate cell list for the terminal to perform cell switching according to the obtained network information.

The network information of the neighboring cell may reflect a network condition of the neighboring cell, and the terminal switches to the neighboring cell with a better network condition, which is beneficial for the terminal to perform subsequent communication.

Specifically, the candidate cell list for the terminal to perform cell handover may be determined through at least one of the following steps a to C.

Step A: and selecting the cells with the signal intensity higher than the preset signal intensity in the adjacent cells to obtain a candidate cell list comprising the selected cells.

Specifically, the Signal strength may be expressed in terms of RSRP (Reference Signal Receiving Power), which is expressed in dB, and the predetermined Signal strength may be-105 dBm, for example.

The higher the signal intensity of the cell in which the terminal is located is, the better the communication effect of the terminal in the communication process is, so that the cell with the signal intensity higher than the preset signal intensity is selected as the candidate cell, the signal intensity of the target cell selected by the terminal from the candidate cells is higher, and the communication effect is better after the terminal is switched to the target cell.

In an embodiment of the present invention, cells with a total number less than or equal to a preset number of first cells may be selected as candidate cells from neighboring cells with a signal strength higher than a preset signal strength. Specifically, a cell may be randomly selected from neighboring cells having a signal strength higher than a preset signal strength, or a neighboring cell having a highest signal strength may be selected as the candidate cell. For example, the preset number of first cells may be 4, 6, or 8.

And B: and selecting the cells with the network load smaller than the preset network load in the adjacent cells to obtain a candidate cell list comprising the selected cells.

The lower the network load of the cell in which the terminal is located is, the better the communication effect of the terminal in the communication process is, so that the cell with the network load smaller than the preset network load is selected as the candidate cell, the network load of the target cell selected by the terminal from the candidate cells is lower, and the communication effect is better after the terminal is switched to the target cell.

The preset network load may be 50%, 60%, or the like.

In an embodiment of the present invention, cells with a total number less than or equal to a preset number of second cells may be selected as candidate cells from neighboring cells with a network load less than a preset network load. Specifically, a cell may be randomly selected from neighboring cells with a network load smaller than a preset network load or a neighboring cell with a lowest load may be selected as the candidate cell.

The preset number of second cells may be the same as or different from the preset number of first cells, for example, the preset number of second cells may be 4, 6, or 8.

And C: and obtaining historical cell switching information of the terminal, and obtaining a candidate cell list from candidate cells in the cells which are switched by the terminal in history according to the obtained network information and the historical cell switching information.

The candidate cell may be determined based on the history cell switching information of the terminal, because each cell to which the terminal has been switched may be determined based on the history cell switching information of the terminal, and the terminal may be more suitable for switching to the candidate cell if the terminal switches to a neighboring cell for multiple times.

In addition, in the process of the terminal communicating based on the source base station, a HANDOVER REQUEST and a RESPONSE message of terminal CONTEXT information may be sent to the source base station, the message may carry the historical cell HANDOVER information, and the source base station may store the carried historical cell HANDOVER information after receiving the message, so that the source base station obtains the historical cell HANDOVER information.

Specifically, the history cell switching information may be a set of identifiers of cells to which the terminal has historically switched, and the identifiers of the cells may be cell names, cell numbers, and the like. The set may be represented in the form of an array, a string set, a heap, a stack, a list, or the like.

After the terminal performs cell switching, the terminal may add the identifier of the cell to which the terminal is switched to historical cell switching information, where the historical cell switching information may include the identifiers of the cells with the preset identifier number at most, and when the number of the included identifiers of the cells reaches the preset identifier number, the terminal may delete the identifier of the cell with the earliest switching time and add the identifier of the cell to which the terminal is currently switched to the historical cell switching information. For example, the preset number of identifications may be 20, 30, etc.

In an embodiment of the present invention, the candidate cell for the terminal to perform cell handover may be directly determined from the cells that have been historically handed over by the terminal, so as to obtain the candidate cell list, or the candidate cell may be determined from the cells that have been handed over by the terminal for a number greater than a preset number, so as to obtain the candidate cell list. For example, the predetermined number of times may be 2 times, 5 times, or the like.

In addition, a neighbor cell satisfying at least one of the conditions, at least two of the conditions, or all three of the conditions in the above steps a to C may be determined as the above candidate cell.

S103: instructing the terminal to perform CHO based on the determined candidate cell list.

The terminal carries out condition monitoring on the candidate cells in the candidate cell list based on CHO, determines the candidate cells meeting the preset switching conditions as target cells, and switches to the target cells to complete CHO switching.

Specifically, the step S103 can be realized through the steps S103A-S103C, which will not be detailed herein.

As can be seen from the above, the source base station does not directly determine the candidate cell list including the predetermined number of candidate cells, but determines the candidate cell list according to the network information of the neighboring cell. That is, the network information of the neighboring cell is obtained based on the measurement report reported by the terminal, the candidate cells are dynamically selected, and the candidate cell list is determined, so that the selected candidate cells can be more suitable for the terminal, the number of the selected candidate cells also changes with the change of the network information of the neighboring cell, and a preset number of candidate cells are not selected unchanged. Therefore, it is possible to make the finally selected candidate cell contribute not only to the cell handover of the terminal but also to the exclusion of unnecessary cells from the candidate cells, and thus, the number of candidate cells in the conditional handover process can be controlled.

Referring to fig. 2, a schematic flowchart of a second cell handover method according to an embodiment of the present invention is shown, where, compared with the embodiment shown in fig. 1, the step S102 can be implemented through the following steps S102A-S102C.

S102A: and obtaining the network information of the source cell where the terminal is located.

In an embodiment of the present invention, since the source cell is a cell of a source base station, the source base station may obtain network information of the source cell from recorded information of its own cell.

The network information may include a signal strength of the source cell, historical handover information of a terminal located in the source cell handed over from the source cell, and the like.

Specifically, the historical handover information may include specific handover situations of each terminal in the source cell, for example, whether or not each terminal has successfully handed over, a cell handed over after handover, and the like. The history handover information may be a handover success rate, a handover failure rate, and the like of each terminal in the source cell.

S102B: and determining the maximum number of the candidate cells according to the network information of the source cell.

Wherein, the maximum number is less than or equal to a preset threshold value. Specifically, when the cell handover scheme provided in the embodiment of the present invention is applied to a 5G communication scenario, the preset threshold may correspond to a 5G standard, for example, when the 5G standard is a Release16 standard, the Release16 standard specifies that a source base station may select at most 8 candidate cells, and the preset threshold may be 8.

In an embodiment of the present invention, when the network information of the source cell includes the signal strength of the source cell, the maximum number of candidate cells may be determined through the following steps D to E, which will not be described in detail herein.

In another embodiment of the present invention, when the network information of the source cell includes history handover information for handover of the terminal in the source cell from the source cell, the maximum number of candidate cells may be determined in the following step F, which will not be described in detail herein.

In addition, in the case where the maximum number of candidate cells is determined through both steps D to E and step F, if the maximum numbers determined through the two ways are different, the maximum value, the minimum value, the average value, or the like of the determined maximum numbers may be selected as the finally determined maximum number of candidate cells.

S102C: and determining the candidate cells with the total number not greater than the maximum number and used for cell switching by the terminal according to the obtained network information of the adjacent cells to obtain a candidate cell list.

Specifically, the candidate cell may be determined through the embodiment shown in step S102, which is not described herein again. If the number of candidate cells determined in the embodiment of step S102 is less than or equal to the maximum number, the determined candidate cells may be directly used as the finally determined candidate cells.

If the number of candidate cells determined by the embodiment of the foregoing step S102 is greater than the above-mentioned maximum number, the finally determined candidate cells may be obtained by at least one of the following manners (one) to (three).

And (I) selecting the largest number of cells with the highest signal strength from the determined candidate cells as the finally determined candidate cells.

And (II) selecting the largest number of cells with the lowest network load from the determined candidate cells as the finally determined candidate cells.

And (c) selecting the maximum number of cells with the highest historical switching times from the determined candidate cells as the finally determined candidate cells.

As can be seen from the above, with the solution provided in the embodiment of the present invention, the number of candidate cells determined by the source base station is less than or equal to the maximum number, so that the number of candidate cells can be controlled within the maximum number. Therefore, in the process that the terminal performs cell switching on the determined candidate cells, the number of the candidate cells which are required to be subjected to condition monitoring by the terminal does not exceed the maximum number, and the control of the number of the candidate cells is realized. And the maximum number is dynamically determined by the source base station according to the network information of the source cell, so that the determined maximum number can be more suitable for the source base station, and cell switching of the terminal is facilitated.

In an embodiment of the present invention, when the network information of the source cell includes the signal strength of the source cell, the maximum number of candidate cells may be determined through the following steps D to E.

Step D: and obtaining a speed type representing the moving speed of the terminal according to the signal strength and the reference signal strength of the source cell.

Specifically, the speed type may be a preset speed type, for example, the speed type may include a high speed movement type, a medium speed movement type, a low speed movement type, and the like.

In an embodiment of the present invention, a difference between the reference signal strength and the signal strength of the source cell may be calculated, a preset difference interval to which the calculated difference belongs may be determined, and a speed type representing the moving speed of the terminal may be determined according to a correspondence between a preset speed type and the preset difference interval.

For example, if the calculated difference is equal to or less than a first difference, the velocity type is considered as a low-velocity movement type, if the calculated difference is greater than the first difference and equal to or less than a second difference, the velocity type is considered as a medium-velocity movement type, and if the calculated difference is greater than or equal to the second difference, the velocity type is considered as a high-velocity movement type. Wherein the first difference is smaller than the second difference.

In another embodiment of the present invention, a ratio between the reference signal strength and the signal strength of the source cell may also be calculated, a preset ratio interval to which the calculated ratio belongs is determined, and a speed type representing the moving speed of the terminal is determined according to a corresponding relationship between a preset speed type and the preset ratio interval.

For example, if the calculated ratio is equal to or less than a first ratio, the speed type is considered as a low-speed movement type, if the calculated difference is greater than the first ratio and equal to or less than a second ratio, the speed type is considered as a medium-speed movement type, and if the calculated difference is greater than or equal to the second ratio, the speed type is considered as a high-speed movement type. Wherein the first ratio is smaller than the second ratio.

In addition, the reference signal strength may be a preset fixed value, for example, -90 dBm. The signal strength may be determined based on a historical signal strength of the source cell when the terminal in the source cell is handed out from the source cell.

Specifically, the reference signal strength may be a historical signal strength of the source cell when a device that was last handed out from the source cell was handed out from the source cell. The reference signal strength may be calculated by selecting candidate devices among the devices to be handed out from the source cell, and calculating a maximum value, a minimum value, an average value, or the like of the historical signal strengths of the source cell when the candidate devices are handed out from the source cell.

All the devices switched out from the source cell may be selected as candidate devices, or some of the devices switched out from the source cell may be randomly selected as candidate devices, or devices having a time difference smaller than a preset time difference between the switching-out time and the current time may be selected as candidate devices, or a preset number of devices having the smallest time difference between the switching-out time and the current time may be selected as candidate devices.

For example, the preset time difference may be 1h, 5h, and the like, and the number of the preset devices may be 3, 4, and the like.

Further, since the terminal becomes a device to be handed out from the source cell after the terminal is handed out from the source cell, the reference signal strength may be updated based on the signal strength when the terminal is handed out from the source cell, and may be used by the device in the source cell in a process of performing cell handover thereafter.

Step E: based on a first principle for the above speed types, a maximum number of candidate cells is determined.

Wherein, the first principle is as follows: the higher the speed characterized by the speed type, the larger the maximum number of candidate cells.

Specifically, as the moving speed of the terminal is faster, the time required for the terminal to leave the coverage of the source cell is shorter, so that a larger number of candidate cells can be selected, the terminal can determine the target cell from the larger number of candidate cells, and the possibility that the terminal determines the target cell from the candidate cells in a short time is improved.

In an embodiment of the present invention, the maximum number of candidate cells may be determined according to a correspondence between a preset speed type and the maximum number of candidate cells.

For example, the maximum number for the low speed type is 2, the maximum number for the medium speed type is 4, the maximum number for the high speed type is 6, and so on.

Specifically, when it is determined that the maximum number of candidate cells is 1, the terminal has only 1 candidate cell for cell handover, that is, the terminal may only be handed over to the candidate cell, and there are no other candidate cells for the terminal to perform CHO handover selection, so that the source base station may instruct the terminal to perform cell handover based on a conventional handover method.

Wherein, the conventional switching method is as follows: and the source base station determines a target cell and indicates the mode that the terminal is directly switched to the target cell, and compared with the CHO switching mode, the terminal does not need to select the target cell from the candidate cells.

In another embodiment of the present invention, when the network information of the source cell includes history handover information that a terminal in the source cell handed out from the source cell, the determination of the maximum number of candidate cells may be performed in the following step F.

Step F: based on a second principle for historical hand-out information, a maximum number of candidate cells is determined.

Wherein, the second principle is as follows: the higher the handover failure rate represented by the historical handover information is, the larger the maximum number of candidate cells is.

The above-mentioned cut-out failure rate was: probability of failure of the device to hand out from the source cell.

Specifically, the device has a high handover failure rate from the source cell, which indicates that the terminal has a high probability of handover failure from the source cell, so that a larger number of candidate cells can be selected, and the terminal can determine a target cell from the larger number of candidate cells to improve the probability of successful handover of the terminal.

In an embodiment of the present invention, when the history handover information includes specific handover situations of the devices that have a history in the source cell, the handover failure rate may be calculated according to information on whether the devices have successfully handed over. When the history handover information includes the handover success rate, a difference between 1 and the handover success rate may be calculated as the handover failure rate. When the historical extraction information includes the extraction failure rate, the extraction failure rate may be directly specified.

In addition, the maximum number corresponding to the above-mentioned cut-out failure rate may be determined according to a preset correspondence between the cut-out failure rate and the maximum number. The correspondence may be a linear relationship or a piecewise relationship, and the piecewise relationship indicates that the maximum numbers corresponding to the handover failure rates included in the same handover failure rate interval are the same. Then, the handover failure rate interval to which the handover failure rate belongs may be determined, and the maximum number corresponding to the determined handover failure rate interval is used as the maximum number of candidate cells.

For example, the maximum number is 2 when the cut-out failure rate is equal to or less than the first cut-out failure rate, 5 when the cut-out failure rate is greater than the first cut-out failure rate and equal to or less than the second cut-out failure rate, and 8 when the cut-out failure rate is greater than the second cut-out failure rate. The second cut-out failure rate is greater than the first cut-out failure rate.

Referring to fig. 3A, a flowchart of a third cell handover method according to an embodiment of the present invention is shown, and compared with the foregoing embodiment shown in fig. 1, the foregoing step S103 may be implemented by the following steps S103A-S103C.

S103A: a CHO request is sent to the candidate base stations of the candidate cells in the determined candidate cell list.

Specifically, the CHO request indicates that the terminal may handover to the candidate cell. The candidate base station needs to reserve resources for a terminal which is possibly switched to a candidate cell after receiving the CHO request, and sends a CHO command which indicates that the candidate cell is available for the terminal to switch to the source base station.

S103B: and receiving a CHO command sent by the candidate base station.

The CHO command may carry cell configuration information of the candidate cell.

S103C: and sending a CHO execution condition for performing CHO switching and the received CHO command to the terminal so that the terminal performs CHO switching when the CHO execution condition is met based on the CHO command aiming at the candidate cell.

Specifically, the source base station may send a Radio Resource Control (RRC) configuration message carrying a CHO execution condition and a CHO command to the terminal, so as to send the CHO execution condition and the CHO command to the terminal.

After receiving the RRC configuration message, the terminal may transmit a Radio Resource Control configuration complete message to the source base station, indicating that the terminal has received the CHO execution condition and the CHO command, and start CHO handover when the CHO execution condition is satisfied based on the CHO command for the candidate cell.

Specifically, the above steps S103A-S103C are similar to the CHO handover process described in fig. 3B and 3C, and will not be described in detail here.

As can be seen from the above, after the source base station determines the candidate cell, a CHO request may be sent to the candidate base station of the candidate cell, and only the candidate base station that receives the CHO request may send a CHO command to the source base station. Therefore, after the source base station transmits the CHO execution condition and the received CHO command to the terminal, the terminal can also receive the CHO execution condition for performing the CHO handover and the CHO command of the candidate cell. Therefore, in the process of performing the CHO handover by the terminal based on the CHO command for the candidate cell, only the candidate cell is subjected to condition monitoring, and other cells are not subjected to condition monitoring. And after the terminal determines that the target cell meeting the CHO execution condition exists in the candidate cells, the target cell is switched to the target cell, so that the cell switching is realized.

Moreover, because the number of candidate cells is small, only a small number of candidate base stations of the candidate cells reserve resources for the terminal after receiving the CHO request, and other base stations do not reserve resources for the terminal, so that the total resource amount of resources reserved for the terminal by each base station in the process of CHO handover by the terminal is small, and the influence on the normal work of other base stations is small.

Referring to fig. 3B, a schematic view of an application scenario for performing cell handover based on a CHO method according to an embodiment of the present invention is shown.

The solid oval area represents a source cell, the dotted oval area represents a candidate cell, the terminal is located in the source cell, the terminal realizes network communication based on a source base station of the source cell, and an arrow between the terminal and the source base station represents that data transmission can be performed between the terminal and the source base station. In addition, candidate cells of a plurality of candidate base stations exist, and an arrow between the source base station and the candidate base station indicates that data transmission can be performed between the source base station and the candidate base station.

Referring to fig. 3C, a schematic flow chart of performing cell handover based on a CHO method according to an embodiment of the present invention is shown.

Specifically, before the terminal is handed over to the target cell of the target base station, the target base station is one of the candidate base stations, and the operation performed by the candidate base station is the same, so fig. 3C does not show the steps performed by the target base station before the terminal is handed over to the target cell, and the steps performed by the target base station before the terminal is handed over to the target cell can be referred to the steps performed by the candidate base station.

S301: and the terminal monitors each adjacent cell to obtain the network information of each adjacent cell.

S302: the terminal transmits a measurement report including network information of each neighbor cell to the source base station.

S303: and the source base station determines to adopt a CHO mode to control the terminal to carry out cell switching according to the network information of each adjacent cell contained in the received measurement report.

S304: the source base station selects a candidate cell from the neighboring cells.

S305: and the source base station sends a CHO request to the candidate base station.

S306: and the candidate base station reserves resources required by the terminal to be switched to the candidate cell.

S307: and the candidate base station sends a CHO command of the candidate cell to the source base station.

S308: the source base station sends a CHO command of the candidate cell and a CHO execution condition generated by the source base station to the terminal.

S309: and the terminal sends an information receiving confirmation to the source base station.

S310: and the terminal carries out condition monitoring on each candidate cell.

S311: the source base station performs Early Status Transfer (Early Status Transfer) to the candidate base station.

S312: and the terminal disconnects the connection with the source base station and switches to the target cell under the condition that the terminal monitors that the target cell meeting the CHO execution condition exists in the candidate cells.

S313: and the target base station sends information representing the successful switching of the terminal cell to the source base station.

S314: the source base station transmits SN (Sequence Number) status information to the target base station.

S315: and the source base station sends information representing cell switching cancellation to the candidate base station.

S316: and the candidate base station releases the reserved resources required by the terminal to be switched to the candidate cell.

Specifically, the above steps S301 to S316 are substantially the same as the procedure of performing cell handover based on the CHO manner in the prior art, and are not described again in this embodiment of the present invention.

Referring to fig. 4, a flowchart of a fourth cell handover method according to an embodiment of the present invention is shown, and compared with the embodiment shown in fig. 3A, the step S103B can be implemented by the following step S103B 1.

S103B 1: and receiving a CHO command sent by the candidate base station within a preset time length from the source base station sending the CHO request.

Specifically, there is a time difference between the time when the source base station receives the CHO command and the time when the source base station transmits the CHO request, which is affected by the network condition, the data processing speed of the candidate base station, and other factors. The smaller the time difference is, the better the network condition of the communication between the source base station and the candidate base station is, the higher the data processing speed of the candidate base station is, the terminal is switched to the candidate cell of the candidate base station with the higher data processing speed, so that the communication effect of the terminal after cell switching can be better.

In an embodiment of the present invention, the source base station may set a timer, the timer is started when the source base station sends a CHO request, a timing duration of the timer may be set to the preset duration, and after the timing duration of the timer reaches the preset duration, the source base station does not receive the CHO command sent by the candidate base station. If the source base station has received the CHO commands sent by all candidate base stations before the timing duration of the timer reaches the preset duration, the timing may be terminated. For example, the preset time period may be 100ms, 300ms, or the like.

In another embodiment of the present invention, after obtaining each CHO command sent by the candidate base station, a time difference between a time when the CHO command is received and a time when the source base station sends the CHO request may be determined, and the CHO command with the time difference less than or equal to a preset time length may be retained.

In addition, after each time a CHO command sent by a candidate base station is received, a time difference between the time when the CHO command is received and the time when the source base station sends the CHO request is determined, and until the time difference corresponding to the received CHO command is greater than the preset time length, the last time the CHO command is received is cleared, and the CHO command reception is stopped.

As can be seen from the above, the CHO command received by the source base station is a CHO command sent by the candidate base station within a preset time period from the sending of the CHO request by the source base station. The received CHO command can therefore be considered to be a CHO command sent by a candidate base station with a higher data processing speed. Therefore, the terminal performs cell switching based on the CHO command received by the source base station, so that the data processing capacity of the candidate base station corresponding to the target cell to which the terminal is switched is stronger, and the communication effect of the terminal after cell switching is better. In addition, since a part of the CHO commands is sent to the source base station after a preset time period since the source base station sends the CHO request, the source base station does not receive the part of the CHO commands any more, so that the terminal does not obtain the part of the CHO commands, and the terminal does not perform condition monitoring on the candidate cells corresponding to the part of the CHO commands, thereby further controlling the number of the candidate cells which need to be monitored in the cell switching process of the terminal.

Referring to fig. 5, a schematic flowchart of a fifth cell handover method according to an embodiment of the present invention is shown, where, compared with the embodiment shown in fig. 3A, the step S103C can be implemented by the following steps S103C1-S103C 2.

S103C 1: and if the total data volume of the received CHO commands is larger than the preset maximum data volume, selecting the CHO commands with the sum of the data volumes less than or equal to the maximum data volume according to the data volume of each CHO command and the maximum data volume.

Specifically, the maximum data size may be a preset fixed data size, for example, the limit of the R15 protocol involved in 5G communication on the maximum data size of a CHO command that can be stored by a terminal is often 34 kbytes, and the fixed data size may be 34 kbytes. The maximum data amount of the CHO command that can be accommodated by the RRC buffer may be set when the data amount that can be accommodated by the RRC buffer (Radio Resource Control buffer) for storing the CHO command in the terminal is limited.

The data size of the RRC buffer may be related to a protocol used by the terminal when performing communication, for example, in a scenario where the terminal is in a DC/CA (Dual-Connectivity/Carrier Aggregation) environment, for the R15 protocol, the data size of the RRC buffer may be 45 kbytes, and the RRC buffer stores configuration information of the source cell, measurement configuration information, and a CHO execution condition in addition to the CHO command. In most cases, the data size of the configuration information and the measurement configuration information of the source cell is often less than or equal to 9 kbytes, the data size of the CHO execution condition is often less than or equal to 2 kbytes, and the remaining storage space in the RRC buffer may be used for storing the CHO command. In most cases, the RRC buffer may store CHO commands for up to 8 candidate cells.

In an embodiment of the present invention, a total data amount of the CHO commands may be determined, and when the total data amount is greater than a preset maximum data amount, the CHO commands may be sequentially removed in an order from a large data amount to a small data amount or from a small data amount to a large data amount of each CHO command until a sum of data amounts of the remaining CHO commands is less than or equal to the maximum data amount. The remaining CHO commands are the selected CHO commands.

In addition, the difference between the total data amount of each CHO command and the maximum data amount may be calculated, and the CHO command whose sum of data amounts is equal to or greater than the difference and closest to the difference may be removed.

Specifically, the CHO command may be deleted to remove the CHO command, or the CHO command may be retained but not transmitted to the terminal, which corresponds to the removal of the CHO command.

In another embodiment of the invention, the CHO command may also be selected by the following steps G-H.

Step G: the signal strength of each candidate cell is determined.

The signal strength of the candidate cell may be a signal strength included in a measurement report that is reported by the terminal to the source base station.

Step H: and selecting the CHO commands with the sum of the data quantity less than or equal to the maximum data quantity according to the signal strength of the candidate cell corresponding to each CHO command, the data quantity of each CHO command and the maximum data quantity.

In an embodiment of the present invention, the CHO commands corresponding to each candidate cell may be sequentially removed in an order from small to large of the signal strength of the candidate cell until the sum of the data amounts of the remaining CHO commands is less than or equal to the maximum data amount. The remaining CHO commands are the selected CHO commands.

In another embodiment of the present invention, a difference between the signal strength of each candidate cell and the data amount of the CHO command corresponding to each candidate cell may be calculated, and the larger the calculated difference is, the higher the priority of the CHO command is. And sequentially removing the CHO commands corresponding to the candidate cells according to the sequence from low priority to high priority until the sum of the data quantity of the remaining CHO commands is less than or equal to the maximum data quantity. The remaining CHO commands are the selected CHO commands.

Specifically, since there is a difference between the magnitude of the signal strength and the magnitude of the data amount, if the signal strength and the data amount are directly subtracted, the difference between the calculated differences may be small, and it is difficult to prioritize the CHO commands. Therefore, the data amount can be divided by the preset dividend to obtain a calculation result. Calculating a difference between the signal strength and the calculation result as the priority. For example, the predetermined dividend may be 19.

S103C 2: and sending the CHO execution condition and the selected CHO command to the terminal so that the terminal performs CHO switching based on the selected CHO command when the CHO execution condition is met.

Specifically, since the sum of the data amounts of the CHO commands sent by the source base station to the terminal is less than or equal to a preset maximum data amount, that is, under the condition that the size of the storage space of the RRC buffer is limited, the RRC buffer can store the CHO command sent by the source base station to the terminal, so that the terminal can perform cell handover normally.

As can be seen from the above, since the sum of the data amounts of the selected CHO commands is equal to or less than the total data amount, the terminal can store the selected CHO commands, and the terminal can perform cell handover normally according to the CHO commands. In addition, since the terminal only receives the selected CHO command and only performs condition monitoring on the candidate cells corresponding to the received CHO command, the number of candidate cells that the terminal needs to perform condition monitoring can be further controlled.

Referring to fig. 6, a flowchart of a sixth cell handover method according to an embodiment of the present invention is shown, and compared with the embodiment shown in fig. 1, the method further includes the following steps S104 to S105 after the step S103.

Specifically, the source base station may perform the following steps S104 to S105 in the process of performing step S103 to instruct the terminal to perform cell handover with respect to the determined candidate cell based on CHO, but the terminal has not completed cell handover.

S104: and determining whether the switching environment of the terminal for CHO switching is changed.

Specifically, the change of the handover environment of the CHO handover performed by the terminal may be caused by a change of an environment of the candidate cell monitored by the terminal in the process of monitoring the condition of the candidate cell, or caused by a change of the environment of the candidate cell monitored by the source base station, or caused by a change of the environment of the source base station determining the source cell.

The change of the handover environment may be that the network load of the candidate base station of the candidate cell has reached the maximum network load, and the communication service cannot be provided for the terminal subsequently handed over to the candidate cell.

In an embodiment of the present invention, whether the handover environment of the terminal performing the CHO handover is changed may be determined through the following step I and/or step J.

Step I: and if receiving the cell leaving instruction sent by the terminal, determining that the switching environment of the terminal for CHO switching is changed.

Wherein the cell departure indication is used for characterizing: one or more of the candidate cells do not satisfy the handover requirements of the terminal.

Specifically, the terminal may be configured to start cell leaving monitoring, that is, the terminal may monitor whether the candidate cell meets a handover requirement of the terminal in a process of performing condition monitoring on the candidate cell. The reportOnLeave attribute value of the terminal may be set to true, which indicates that the terminal starts cell departure monitoring, and otherwise, if the reportOnLeave attribute value of the terminal is set to false, the terminal does not perform cell departure monitoring.

Because the probability of switching the terminal to the candidate cell which does not meet the switching requirement is low, the terminal can stop performing condition monitoring on the candidate cell which does not meet the switching requirement, and data processing resources are saved. Therefore, when one or more of the candidate cells do not satisfy the handover request, the handover environment in which the terminal performs the cell handover may be changed.

In an embodiment of the present invention, a terminal may start leaving event reporting, and in a process of performing condition monitoring on candidate cells by the terminal, the terminal may send information characterizing that one or more cells in the candidate cells do not meet a handover requirement to the source base station when monitoring that one or more of the candidate cells do not meet the handover requirement, that is, when one or more candidate cells trigger a leaving event. The source base station may execute the step S105 to update the CHO command of the candidate cell for the terminal, and notify the candidate base station corresponding to the candidate cell that does not satisfy the handover requirement, so that the candidate base station releases the resource reserved for the terminal handover.

Specifically, the terminal may determine that one or more cells of the candidate cells do not satisfy the handover requirement under the condition that Mn + Ofn + Ocn + Hys < Thresh.

Wherein, Mn is a candidate cell measurement result, Ofn is a specific frequency offset of a candidate cell frequency, Ocn is a specific cell offset of a candidate cell, hy is a leaving event hysteresis, and Thresh is a leaving event threshold.

The value of Ofn may be determined by a parameter QoffsetFreq, which is issued in a measurement object of a measurement control message transmitted from the source base station to the terminal. The value of Ocn may be determined by a parameter CellIndividualOffset, and is not issued when the value of parameter CellIndividualOffset is zero, and is issued in the measurement control message when the value of parameter CellIndividualOffset is not zero. The value of Hys may be issued by a parameter hysteris in the measurement configuration information included in the CHO command. The value of Threshold may be issued by a parameter a4-Threshold in the measurement configuration information.

Step J: and if other switching modes are triggered, determining that the switching environment of the CHO switching performed by the terminal is changed.

The switching method other than the CHO method may be a conventional switching method.

Specifically, if the source base station determines that the terminal performs cell handover in a handover mode other than the CHO mode, which is more beneficial to improving system performance, the source base station may trigger other handover modes to indicate that the terminal can perform cell handover based on the other handover modes. The source base station may send a handover command of another handover method to the terminal, and thus may perform step S105 to update the handover command.

After receiving the handover command of the other handover method, the terminal may perform cell handover based on the other handover method and terminate the cell handover in the CHO method.

S105: and if the switching environment is changed, updating the CHO command of the candidate cell for the terminal to perform the CHO switching, and transmitting the updated CHO command to the terminal.

In one embodiment of the invention, the CHO command of the candidate cell may be updated by the following step K and/or step L.

Step K: and according to the network information of the adjacent cell, re-determining the candidate cell for the terminal to perform the CHO switching, and obtaining the re-determined CHO command.

Specifically, the steps S101 to S103 may be executed again, the candidate cell may be determined again, and the CHO command of the candidate cell may be determined again, where the CHO command of the candidate cell may be determined again in a manner similar to the manner of obtaining the CHO command, which is not described again here.

Step L: according to the changed switching environment, part of the CHO command is deleted from the CHO commands transmitted to the terminal.

In an embodiment of the present invention, when receiving the cell leaving indication sent by the terminal and determining that the handover environment for the terminal to perform cell handover changes, the CHO command of the candidate cell that does not satisfy the handover requirement may be deleted.

In another embodiment of the present invention, when another handover method is triggered and it is determined that the cell handover condition of the terminal is changed, the source base station needs to transmit a handover command to the terminal, the handover command instructing the terminal to perform cell handover based on the another handover method. Therefore, it is necessary to delete part of the CHO command that has been sent to the terminal, so that the remaining storage space of the terminal can store the handover command of another handover method.

Specifically, the original CHO commands may be determined sequentially according to the sequence of the data amount from small to large or from large to small until the sum of the data amounts of the determined original CHO commands is greater than or equal to the data amount of the handover command of the other handover mode. Deleting the determined original CHO command.

Further, the original CHO command whose sum of data amounts is equal to or larger than the data amount of the handover command of the other handover method and which is closest to the data amount of the handover command of the other handover method may be specified in the original CHO command, and the specified original CHO command may be deleted.

As can be seen from the above, when the handover environment for the terminal to perform cell handover changes, the candidate cell to which the terminal can handover changes, so that the handover command of the candidate cell can be updated, and the updated handover command is sent to the terminal, so that the terminal can complete cell handover based on the new handover command. Moreover, the process of cell switching by the terminal can adapt to the change of the switching environment, and the terminal can continue to smoothly complete cell switching after the switching environment changes.

The cell handover scheme provided by the embodiment of the present invention is described below by specific examples.

Assuming that there are 8 neighbor cells, the source base station may select a candidate cell from the 8 neighbor cells. The signal intensity of the source cell is-103 dBm, the reference signal intensity is-95 dBm, and under the condition that the difference value between the reference signal intensity and the signal intensity of the source cell is greater than 6dB, the speed type of the terminal is considered to be a high-speed mobile type, otherwise, the speed type of the terminal is a low-speed mobile type. The terminal starts leaving event reporting, and under a carrier aggregation scene, the terminal is configured with 4 serving cells. See table 1 for information on each neighbor cell.

Table 1 neighbor cell information

Specifically, the source base station may first calculate that a difference between the reference signal strength and the signal strength of the source cell is 8dBm and greater than 6dB, and therefore, considering that the velocity type of the terminal is a high-speed mobile type, the maximum number of the selected candidate cells may be 8.

In addition, the source base station may screen a neighboring cell with a signal strength, that is, RSRP greater than-105 dBm, the neighboring cell obtained by the screening is a neighboring cell 1-8, then screen a neighboring cell with a network load less than 50%, the neighboring cell obtained by the screening is a neighboring cell 1-7, then screen a neighboring cell switched by the terminal, and the neighboring cell obtained by the screening is a neighboring cell 1-6, then determine the neighboring cell 1-6 as a candidate cell.

Further, the source base station sends a CHO request to the candidate base stations corresponding to the screened candidate cells, i.e., the neighboring cells 1 to 6, and receives a CHO command sent by the candidate base stations within 100ms from the source base station sending the CHO request. Since the receiving delay of the neighboring cell 1-5 is less than 100ms, that is, the time difference between the time when the source base station receives the CHO command sent by the candidate base station of the neighboring cell 1-5 and the time when the source base station sends the CHO request is less than 100ms, the source base station may receive the CHO command sent by the candidate base station of the neighboring cell 1-5.

In addition, the information of the CHO command corresponding to each neighbor cell is referred to table 2.

Table 2 information of CHO command corresponding to neighbor cell

Specifically, referring to table 2, the terminal sends a measurement report to the source base station, indicating that it is determined that the neighboring cell 5 leaves, so that the source base station may remove the neighboring cell 5 from the candidate cells, and the remaining candidate cells are neighboring cells 1 to 4.

Furthermore, the size of the configuration information of the 4 serving cells configured by the terminal is 9 kbytes, the size of the measurement configuration information of the terminal is 8 kbytes, and the size of the storage space of the RRC buffer is 45 kbytes, so that the source base station may consider that the size of the storage space of the remaining RRC buffer of the terminal is 45k-9k 4-8 k-1 kbyte-8 kbytes, and considering that the size of the storage space required to be reserved in the RRC buffer is 1500bits, the terminal can only store the CHO command of 6500bits again. However, the total data volume of the CHO commands corresponding to the neighboring cells 1 to 4 is 6840bit, so that the terminal cannot store all the CHO commands corresponding to the neighboring cells 1 to 4. Selection needs to be made in the CHO commands corresponding to the neighbor cells 1-4. The source cell may sequentially select, according to the calculated priority, CHO commands with the sum of sub-data amounts less than or equal to 6500bits as much as possible in the order from high priority to low priority, and may sequentially select the CHO commands of the neighboring cell 1, the neighboring cell 4, and the neighboring cell 2, where the sum of sub-data amounts of the CHO commands of the neighboring cells 1, 2, and 4 is 4900 bits and less than 6500bits, and clear the CHO command of the neighboring cell 3. And the source base station transmits a CHO command of the selected neighbor cells 1, 2 and 4 to the terminal. And the terminal takes the adjacent cell 1, the adjacent cell 2 and the adjacent cell 4 as candidate cells in the process of cell switching, and carries out condition monitoring on the 3 cells until a target cell contained in the 3 cells is determined, and the terminal is switched to the target cell.

Therefore, in the prior art, the source base station directly determines the neighboring cells 1 to 8 as candidate cells, and the terminal monitors the conditions of 8 cells in total of the neighboring cells 1 to 8. However, in the scheme provided by the embodiment of the present invention, the terminal only performs condition monitoring on the neighboring cells 1, 2, and 4. It can be seen that compared with the prior art, the number of candidate cells is controlled in the process of cell handover.

Corresponding to the foregoing cell switching method, referring to fig. 7, a schematic structural diagram of a cell switching apparatus according to an embodiment of the present invention is shown, where the apparatus includes:

an information obtaining module 701, configured to obtain network information of a neighboring cell according to a neighboring cell list in a measurement report reported by a terminal;

a cell determining module 702, configured to determine, according to the obtained network information, a candidate cell list for the terminal to perform cell handover;

a handover instructing module 703, configured to instruct the terminal to perform conditional handover CHO based on the determined candidate cell list.

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

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

In an embodiment of the present invention, the cell determining module 702 is specifically configured to:

determining a candidate cell list for cell switching of the terminal by at least one of the following modes:

selecting a cell with signal strength higher than preset signal strength in the adjacent cells to obtain a candidate cell list comprising the selected cell;

selecting a cell with a network load smaller than a preset network load in the adjacent cell to obtain a candidate cell list comprising the selected cell;

and acquiring historical cell switching information of the terminal, and determining candidate cells from cells which are switched by the terminal in history according to the acquired network information and the historical cell switching information to obtain a candidate cell list.

In an embodiment of the present invention, the cell determining module 702 includes:

the information obtaining submodule is used for obtaining the network information of the source cell where the terminal is located;

the quantity determining submodule is used for determining the maximum quantity of the candidate cells according to the network information of the source cell;

and the cell determining submodule is used for determining the candidate cells which are not more than the maximum number and are used for cell switching of the terminal according to the obtained network information of the adjacent cells, so as to obtain a candidate cell list.

As can be seen from the above, with the solution provided in the embodiment of the present invention, the number of candidate cells determined by the source base station is less than or equal to the maximum number, so that the number of candidate cells can be controlled within the maximum number. Therefore, in the process that the terminal performs cell switching on the determined candidate cells, the number of the candidate cells which are required to be subjected to condition monitoring by the terminal does not exceed the maximum number, and the control of the number of the candidate cells is realized. And the maximum number is dynamically determined by the source base station according to the network information of the source cell, so that the determined maximum number is more suitable for the source base station, and the cell switching of the terminal is facilitated.

In an embodiment of the present invention, the number determination submodule is specifically configured to:

obtaining a speed type representing the moving speed of the terminal according to the signal strength of the source cell and the reference signal strength;

determining a maximum number of candidate cells based on a first principle for the speed type, wherein the first principle is: the higher the speed characterized by the speed type, the larger the maximum number of candidate cells.

In an embodiment of the present invention, the reference signal strength is: and the signal strength is determined according to the historical signal strength of the source cell when the terminal in the source cell is switched out of the source cell.

In an embodiment of the present invention, the data determination submodule is specifically configured to:

determining a maximum number of candidate cells based on a second principle for historical hand-out information, wherein the second principle is: the higher the handover failure rate represented by the historical handover information is, the larger the maximum number of candidate cells is, the handover failure rate is: probability of device hand-out failure from the source cell.

In an embodiment of the present invention, the switching indication module 703 includes:

a request sending submodule, configured to send a CHO request to a candidate base station of a candidate cell in the determined candidate cell list;

the response receiving submodule is used for receiving the CHO command sent by the candidate base station;

an information sending submodule, configured to send, to the terminal, a CHO execution condition for performing a CHO handover and the received CHO command, so that the terminal performs the CHO handover when the CHO execution condition is satisfied based on the CHO command for the candidate cell.

Moreover, because the number of candidate cells is small, only a small number of candidate base stations of the candidate cells can reserve resources for the terminal after receiving the CHO request, and other base stations cannot reserve resources for the terminal, so that the total resource amount of resources reserved for the terminal by each base station in the CHO handover process of the terminal is small, and the influence on the normal work of other base stations is small.

In an embodiment of the present invention, the response receiving sub-module is specifically configured to:

and receiving a CHO command sent by the candidate base station within a preset time length from the source base station sending the CHO request.

As can be seen from the above, the CHO command received by the source base station is a CHO command sent by the candidate base station within a preset time period from the source base station sending the CHO request. The received CHO command can therefore be considered to be a CHO command sent by a candidate base station with a higher data processing speed. Therefore, the terminal performs cell switching based on the CHO command received by the source base station, so that the data processing capacity of the candidate base station corresponding to the target cell to which the terminal is switched is stronger, and the communication effect of the terminal after cell switching is better. In addition, since a part of the CHO commands is sent to the source base station after a preset time period since the source base station sends the CHO request, the source base station does not receive the part of the CHO commands any more, so that the terminal does not obtain the part of the CHO commands, and the terminal does not perform condition monitoring on the candidate cells corresponding to the part of the CHO commands, thereby further controlling the number of the candidate cells which need to be monitored in the cell switching process of the terminal.

In an embodiment of the present invention, the information sending sub-module includes:

the information selection unit is used for selecting the CHO commands with the sum of the data quantity less than or equal to the maximum data quantity according to the data quantity of each CHO command and the maximum data quantity if the total data quantity of the received CHO commands is greater than the preset maximum data quantity;

an information sending unit, configured to send the CHO execution condition and the selected CHO command to the terminal, so that the terminal performs CHO handover when the CHO execution condition is satisfied based on the selected CHO command.

In an embodiment of the present invention, the information selecting unit is specifically configured to:

if the total data volume of the received CHO commands is larger than the preset maximum data volume, determining the signal intensity of each candidate cell;

and selecting the CHO command with the sum of the data quantity less than or equal to the maximum data quantity according to the signal strength of the candidate cell corresponding to each CHO command, the data quantity of each CHO command and the maximum data quantity.

In one embodiment of the present invention, the apparatus further comprises:

an environment change determining module, configured to determine whether a switching environment for the terminal to perform CHO switching changes;

and the information updating module is used for updating the CHO command of the candidate cell for the terminal to perform the CHO switching under the condition that the environment change determining module determines that the switching environment is changed, and sending the updated CHO command to the terminal.

In an embodiment of the present invention, the environment change determining module is specifically configured to:

if receiving a cell leaving indication sent by the terminal, determining that the switching environment of the terminal for CHO switching is changed, wherein the cell leaving indication is used for representing: one or more of the candidate cells do not satisfy the handover requirements of the terminal;

and/or

And if other switching modes are triggered, determining that the switching environment of the terminal for CHO switching is changed.

In an embodiment of the present invention, the information updating module is specifically configured to:

under the condition that the environment change determining module determines that the switching environment is changed, re-determining a candidate cell for the terminal to perform CHO switching according to the network information of the adjacent cell, and obtaining a re-determined CHO command;

and/or

And deleting part of the CHO command from the CHO commands transmitted to the terminal according to the changed switching environment when the environment change determining module determines that the switching environment is changed.

Corresponding to the foregoing cell switching method, referring to fig. 8, a schematic structural diagram of a base station is provided, as a source base station, and includes a memory 801, a transceiver 802, a processor 803:

a memory 801 for storing a computer program; a transceiver 802 for transceiving data under the control of the processor 803; a processor 803 for reading the computer program in the memory 801 and performing the following operations:

determining a candidate cell list for the terminal to perform cell switching according to the obtained information;

Where in fig. 8 the bus architecture may include any number of interconnected buses and bridges, with one or more processors, represented by the processor 803, and various circuits, represented by the memory 801, being linked together. The bus architecture may also link together various other circuits such as peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further herein. The bus interface provides an interface. The transceiver 802 may be a number of elements including a transmitter and a receiver that provide a means for communicating with various other apparatus over a transmission medium including wireless channels, wired channels, fiber optic cables, and the like. The processor 803 is responsible for managing the bus architecture and general processing, and the memory 801 may store data used by the processor 803 in performing operations.

The processor 803 may be a Central Processing Unit (CPU), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), or a Complex Programmable Logic Device (CPLD), and may also be a multi-core architecture.

As can be seen from the above, the source base station does not directly determine the candidate cell list including the predetermined number of candidate cells, but determines the candidate cell list according to the network information of the neighboring cell. That is, the network information of the neighboring cell is obtained based on the measurement report reported by the terminal, the candidate cells are dynamically selected, and the candidate cell list is determined, so that the selected candidate cells can be more suitable for the terminal, and the number of the selected candidate cells also changes with the change of the network information of the neighboring cell, rather than the unchangeable selection of a preset number of candidate cells. Therefore, it is possible to make the finally selected candidate cell contribute not only to the cell handover of the terminal but also to the exclusion of unnecessary cells from the candidate cells, and thus, the number of candidate cells in the conditional handover process can be controlled.

In an embodiment of the present invention, the determining, according to the obtained network information, a candidate cell list for the terminal to perform cell handover specifically includes:

and obtaining historical cell switching information of the terminal, and determining candidate cells from the cells which are switched by the terminal history according to the obtained network information and the historical cell switching information to obtain a candidate cell list.

In an embodiment of the present invention, the determining a candidate cell list for the terminal to perform cell handover according to the obtained network information specifically includes:

obtaining network information of a source cell where the terminal is located;

determining the maximum number of candidate cells according to the network information of the source cell;

and determining the candidate cells which are not more than the maximum number and are used for cell switching by the terminal according to the obtained network information of the adjacent cells, and obtaining a candidate cell list.

In an embodiment of the present invention, the determining the maximum number of candidate cells according to the network information of the source cell specifically includes:

obtaining a speed type representing the moving speed of the terminal according to the signal intensity of the source cell and the reference signal intensity;

In an embodiment of the present invention, the instructing the terminal to perform a conditional handover CHO based on the determined candidate cell list specifically includes:

sending a CHO request to the candidate base stations of the candidate cells in the determined candidate cell list;

receiving a CHO command sent by a candidate base station;

and sending a CHO execution condition for performing CHO handover and the received CHO command to the terminal so that the terminal performs CHO handover when the CHO execution condition is satisfied based on the CHO command for the candidate cell.

In an embodiment of the present invention, the receiving the CHO command sent by the candidate base station specifically includes:

As can be seen from the above, the CHO command received by the source base station is a CHO command sent by the candidate base station within a preset time period from the source base station sending the CHO request. The received CHO command can therefore be considered to be a CHO command sent by a candidate base station with a higher data processing speed. Therefore, the terminal performs cell handover based on the CHO command received by the source base station, so that the data processing capability of the candidate base station corresponding to the target cell to which the handover is performed is stronger, and the communication effect of the terminal after cell handover is better. In addition, since a part of the CHO commands is sent to the source base station after a preset time period since the source base station sends the CHO request, the source base station does not receive the part of the CHO commands any more, so that the terminal does not obtain the part of the CHO commands, and the terminal does not perform condition monitoring on the candidate cells corresponding to the part of the CHO commands, thereby further controlling the number of the candidate cells which need to be monitored in the cell switching process of the terminal.

In an embodiment of the present invention, the sending, to the terminal, the CHO execution condition for performing the CHO handover and the received CHO command specifically includes:

if the total data volume of the received CHO commands is larger than the preset maximum data volume, selecting the CHO commands with the sum of the data volumes less than or equal to the maximum data volume according to the data volume of each CHO command and the maximum data volume;

sending the CHO execution conditions and the selected CHO commands to the terminal.

In an embodiment of the present invention, the selecting, according to the data amount of each CHO command and the maximum data amount, a CHO command whose sum of the data amounts is less than or equal to the maximum data amount includes:

determining the signal strength of each candidate cell;

In an embodiment of the present invention, after said instructing the terminal to perform conditional handover CHO based on the determined candidate cell list, the method further comprises:

determining whether the switching environment of the terminal for CHO switching is changed;

and if the switching environment is changed, updating the CHO command of the candidate cell for the terminal to perform the CHO switching, and sending the updated CHO command to the terminal.

Therefore, the handover command of the candidate cell can be updated, and the updated handover command is sent to the terminal, so that the terminal can complete cell handover based on the new handover command. Moreover, the process of the cell switching of the terminal can be adapted to the change of the switching environment, and the terminal can continue to smoothly complete the cell switching after the switching environment is changed.

In an embodiment of the present invention, the determining whether a handover environment of the terminal performing the CHO handover changes specifically includes:

and/or

In an embodiment of the present invention, the updating the CHO command of the candidate cell for the terminal to perform the CHO handover specifically includes:

according to the network information of the adjacent cell, re-determining the candidate cell for the terminal to perform the CHO switching, and obtaining a re-determined CHO command;

and/or

And deleting part of the CHO commands from the CHO commands transmitted to the terminal according to the changed switching environment.

In another embodiment provided by the present invention, a computer-readable storage medium is further provided, in which a computer program is stored, and the computer program, when executed by a processor, implements the steps of any of the above cell switching methods.

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

When the computer program stored in the computer-readable storage medium provided in the embodiment of the present invention is executed to control the terminal to perform cell handover, the source base station does not directly determine the candidate cell list including a preset number of candidate cells, but determines the candidate cell list according to the network information of the neighboring cell. That is, the network information of the neighboring cell is obtained based on the measurement report reported by the terminal, the candidate cells are dynamically selected, and the candidate cell list is determined, so that the selected candidate cells can be more suitable for the terminal, the number of the selected candidate cells also changes with the change of the network information of the neighboring cell, and a preset number of candidate cells are not selected unchanged. Therefore, not only can the finally selected candidate cell be helpful for realizing cell switching of the terminal, but also unnecessary cells can be excluded from the candidate cells, and therefore, the number of candidate cells in the conditional switching process can be controlled.

In a further embodiment provided by the present invention, there is also provided a computer program product comprising instructions which, when run on a computer, cause the computer to perform the steps of any of the cell handover methods of the above embodiments.

When the computer program provided by the embodiment of the invention is executed to control the terminal to perform cell switching, the source base station does not directly determine the candidate cell list containing the preset number of candidate cells, but determines the candidate cell list according to the network information of the adjacent cells. That is, the network information of the neighboring cell is obtained based on the measurement report reported by the terminal, the candidate cells are dynamically selected, and the candidate cell list is determined, so that the selected candidate cells can be more suitable for the terminal, the number of the selected candidate cells also changes with the change of the network information of the neighboring cell, and a preset number of candidate cells are not selected unchanged. Therefore, not only can the finally selected candidate cell be helpful for realizing cell switching of the terminal, but also unnecessary cells can be excluded from the candidate cells, and therefore, the number of candidate cells in the conditional switching process can be controlled.

In the above embodiments, the implementation may be wholly or partially realized by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, cause the processes or functions described in accordance with the embodiments of the invention to occur, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, from one website site, computer, server, or data center to another website site, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that incorporates one or more of the available media. The usable medium may be a magnetic medium (e.g., floppy Disk, hard Disk, magnetic tape), an optical medium (e.g., DVD), or a semiconductor medium (e.g., Solid State Disk (SSD)), among others.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in the process, method, article, or apparatus that comprises the element.

All the embodiments in the present specification are described in a related manner, and the same and similar parts among the embodiments may be referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, as for the apparatus, the base station, the storage medium and the computer program embodiment, since they are substantially similar to the method embodiment, the description is relatively simple, and reference may be made to the partial description of the method embodiment for relevant points.

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

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

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

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

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

Claims

1. A method of cell handover, the method comprising:

2. The method of claim 1, wherein the determining the candidate cell list for the terminal to perform cell handover according to the obtained network information comprises:

selecting a cell with a network load smaller than a preset network load in the adjacent cells to obtain a candidate cell list comprising the selected cell;

3. The method of claim 1, wherein the determining the candidate cell list for the terminal to perform cell handover according to the obtained network information comprises:

obtaining network information of a source cell where the terminal is located;

4. The method of claim 3, wherein determining the maximum number of candidate cells according to the network information of the source cell comprises:

5. The method of claim 4, wherein the reference signal strength is: the signal strength is determined according to the historical signal strength of the source cell when the terminal in the source cell is switched out of the source cell.

6. The method of claim 3, wherein determining the maximum number of candidate cells according to the network information of the source cell comprises:

determining a maximum number of candidate cells based on a second principle for historical handover information, wherein the second principle is: the higher the handover failure rate represented by the historical handover information is, the larger the maximum number of candidate cells is, the handover failure rate is: probability of device hand-out failure from the source cell.

7. The method according to any of claims 1-6, wherein said instructing the terminal to perform conditional handover, CHO, based on the determined candidate cell list comprises:

receiving a CHO command sent by a candidate base station;

sending, to the terminal, a CHO execution condition for a CHO handover and the received CHO command, such that the terminal performs the CHO handover when the CHO execution condition is satisfied based on the CHO command for the candidate cell.

8. The method of claim 7, wherein the receiving the CHO command sent by the candidate base station comprises:

9. The method of claim 7, wherein sending the CHO execution conditions for CHO handover to the terminal and the received CHO command comprises:

10. The method according to claim 9, wherein selecting, according to the data amount of each CHO command and the maximum data amount, the CHO command having the sum of the data amounts less than or equal to the maximum data amount comprises:

determining the signal strength of each candidate cell;

11. The method according to any of claims 1-6, wherein after said instructing the terminal to perform conditional handover, CHO, based on the determined candidate cell list, further comprising:

12. The method according to claim 11, wherein said determining whether the handover environment for the terminal performing the CHO handover is changed comprises:

and/or

13. The method of claim 11, wherein the updating the CHO command for the candidate cell for the terminal to perform the CHO handover comprises:

according to the network information of the adjacent cell, re-determining a candidate cell for the terminal to perform CHO handover, and obtaining a re-determined CHO command;

and/or

14. An apparatus for cell switching, the apparatus comprising:

15. A base station, comprising a memory, a transceiver, a processor:

16. The base station of claim 15, wherein the determining the candidate cell list for the terminal to perform cell handover according to the obtained network information specifically comprises:

17. The base station of claim 15, wherein the determining, according to the obtained network information, a candidate cell list for the terminal to perform cell handover specifically includes:

obtaining network information of a source cell where the terminal is located;

18. The base station of claim 17, wherein the determining the maximum number of candidate cells according to the network information of the source cell specifically comprises:

19. The base station of claim 18, wherein the reference signal strength is: the signal strength is determined according to the historical signal strength of the source cell when the terminal in the source cell is switched out of the source cell.

20. The base station of claim 17, wherein the determining the maximum number of candidate cells according to the network information of the source cell specifically comprises:

determining a maximum number of candidate cells based on a second principle for historical handover information, wherein the second principle is: the higher the historical handover failure rate represented by handover failure information is, the larger the maximum number of candidate cells is, the handover failure rate is: probability of device hand-out failure from the source cell.

21. The base station according to any of claims 15 to 20, wherein said instructing the terminal to perform conditional handover, CHO, based on the determined candidate cell list comprises:

sending a CHO request to the candidate base station of the candidate cell in the determined candidate cell list;

receiving a CHO command sent by a candidate base station;

22. The base station of claim 21, wherein the receiving the CHO command sent by the candidate base station specifically comprises:

23. The base station of claim 21, wherein the sending, to the terminal, the CHO execution condition for performing the CHO handover and the received CHO command specifically comprises:

24. The base station according to claim 23, wherein the selecting, according to the data amount of each CHO command and the maximum data amount, the CHO command having a sum of data amounts less than or equal to the maximum data amount comprises:

determining the signal strength of each candidate cell;

25. The base station according to any of claims 15-20, wherein after said instructing the terminal to perform a conditional handover CHO based on the determined candidate cell list, further comprising:

26. The base station of claim 25, wherein the determining whether the handover environment for the terminal to perform the CHO handover is changed comprises:

and/or

27. The base station of claim 25, wherein the updating the CHO command of the candidate cell for the terminal to perform the CHO handover specifically comprises:

and/or

28. A processor-readable storage medium, characterized in that the processor-readable storage medium stores a computer program for causing a processor to perform the method of any one of claims 1 to 13.