CN111698748B

CN111698748B - Network blind switching method, device, base station equipment and storage medium

Info

Publication number: CN111698748B
Application number: CN202010489070.3A
Authority: CN
Inventors: 吴泽先; 王福强; 毛盼盼
Original assignee: Shanghai Wingtech Information Technology Co Ltd
Current assignee: Shanghai Wingtech Information Technology Co Ltd
Priority date: 2020-06-02
Filing date: 2020-06-02
Publication date: 2022-05-03
Anticipated expiration: 2040-06-02
Also published as: CN111698748A

Abstract

The application relates to the technical field of wireless communication, and provides a network blind handover method, a network blind handover device, base station equipment and a computer readable storage medium. The method comprises the following steps: judging whether a blind switching condition is met or not according to the current network condition of the target terminal; if the current network condition reaches the blind switching condition, judging whether no less than a preset number of sample terminals exist in a preset range taking the target terminal as a center, wherein the sample terminals comprise other terminals and the target terminal in the preset range; if the sample terminals not less than the preset number exist, selecting the actual sample terminals of the preset number from the sample terminals; acquiring historical switching data of an actual sample terminal; determining the switching success rate of the adjacent cell to be selected of the target terminal according to the historical switching data; determining a target adjacent cell from the adjacent cells to be selected based on the switching success rate; and switching the current cell of the target terminal to the target adjacent cell. The method can improve the switching success rate of network blind switching.

Description

Network blind switching method, device, base station equipment and storage medium

Technical Field

The present invention relates to the field of wireless communication technologies, and in particular, to a network blind handover method, apparatus, base station device, and storage medium.

Background

In modern wireless communication networks, a cellular network topology is generally adopted, and many other adjacent cells, called neighbor cells, exist around a cell covered by a base station, and when network handover is performed, only one or a few of the neighbor cells are generally suitable as target cells for terminal handover. Network handover is dominated by a network side base station, and generally, the network handover is performed through: the base station issues measurement configuration, the terminal measures the adjacent cell according to the measurement configuration, the terminal reports the measurement result, the base station judges the target cell to be switched according to the measurement result, the base station switches the terminal to the target cell and the like. In the measurement process, the data transmission performance of the terminal is actually sacrificed, and in some cases, in order to maintain the service sustainability of the terminal and the stability of the system, the terminal needs to be switched to the neighboring cell of the current cell as soon as possible, so that the blind handover is adopted to realize the fast network handover.

The blind handover refers to that the base station does not require the terminal to measure the neighboring cell and report the measurement result, but directly commands the terminal to switch to a certain target cell, but because the measurement result is not used as a basis for the base station to select the target cell, handover failure often occurs when the target cell to which the terminal is switched through the blind handover occurs, and repeated failure can also increase network resource consumption. The current blind switching scheme has the disadvantages of low success rate and repeated failure of terminal switching.

Disclosure of Invention

In view of this, the present invention provides a network blind handover method, which can improve the handover success rate of the network blind handover.

In order to solve the technical problem, the invention adopts the following technical scheme:

the embodiment of the application provides a network blind switching method, which comprises the following steps:

judging whether a blind switching condition is met or not according to the current network condition of the target terminal;

if the current network condition reaches a blind switching condition, judging whether no less than a preset number of sample terminals exist in a preset range taking the target terminal as a center, wherein the sample terminals comprise other terminals in the preset range and the target terminal;

if the sample terminals not less than the preset number exist, selecting the actual sample terminals of the preset number from the sample terminals;

acquiring historical switching data of the actual sample terminal;

determining the switching success rate of the adjacent cell to be selected of the target terminal according to the historical switching data;

determining a target adjacent cell from the adjacent cells to be selected based on the switching success rate;

and switching the current cell of the target terminal to the target adjacent cell.

More specifically, in some embodiments, the determining whether the blind handover condition is reached according to the current network condition of the target terminal includes at least one of the following two ways:

judging whether the load amplification of the current cell is greater than a preset amplification or not according to the current network condition, if so, reaching the blind switching condition;

and judging whether the block error rate of the target terminal is increased or not according to the current network condition, if so, reaching the blind switching condition.

More specifically, in some embodiments, after determining whether there are no less than a preset number of sample terminals within a preset range centered on the target terminal, the method further includes:

and if the number of the sample terminals is less than the preset number, selecting the neighbor cell with the lowest load parameter from the neighbor cells to be selected as a target neighbor cell.

More specifically, in some embodiments, the determining a target neighboring cell from the neighboring cells to be selected based on the handover success rate includes:

taking the neighbor cell with the load parameter less than or equal to a preset load value in the neighbor cell to be selected as a first neighbor cell;

determining the switching success rate of each first adjacent cell;

and taking the first adjacent cell with the maximum switching success rate as a target adjacent cell.

More specifically, in some embodiments, the taking the first neighboring cell with the largest handover success rate as the target neighboring cell includes:

dividing the first adjacent cell into an intra-frequency adjacent cell, an inter-frequency adjacent cell and an inter-system adjacent cell according to the network parameters of the first adjacent cell;

determining the inter-frequency switching success rate of each inter-frequency adjacent cell, wherein the inter-frequency switching success rate is the average value of the switching success rates of the actual sample terminal to the corresponding inter-frequency adjacent cells;

judging whether an inter-frequency adjacent region with an inter-frequency switching success rate larger than an inter-frequency success rate threshold exists;

and if so, selecting the inter-frequency adjacent cell with the highest inter-frequency switching success rate as the target adjacent cell.

More specifically, in some embodiments, after the determining whether there is an inter-frequency neighboring cell whose inter-frequency handover success rate is greater than the inter-frequency success rate threshold, the method further includes:

if not, determining the inter-system switching success rate of each inter-system neighboring cell, wherein the inter-system switching success rate is the average value of the switching success rates of the actual sample terminal to the corresponding inter-system neighboring cells;

judging whether an intersystem neighboring cell with an intersystem switching success rate larger than an intersystem success rate threshold exists or not;

and if so, selecting the inter-system neighbor cell with the highest inter-system switching success rate as the target neighbor cell.

More specifically, in some embodiments, after the determining whether there is an intersystem neighboring cell whose success rate of intersystem handover is greater than an intersystem success rate threshold, the method further includes:

if not, determining the intra-frequency switching power of each intra-frequency neighboring cell, wherein the intra-frequency switching power is the average value of the switching success rates of the actual sample terminal to the corresponding intra-frequency neighboring cell;

judging whether an intra-frequency adjacent region with the intra-frequency switching power larger than an intra-frequency power threshold exists;

if the intra-frequency adjacent cell with the intra-frequency switching power larger than the intra-frequency power threshold exists, selecting the intra-frequency adjacent cell with the highest intra-frequency switching power as the target adjacent cell;

and if the intra-frequency adjacent cell with the intra-frequency switching power larger than the intra-frequency power threshold value does not exist, selecting the first adjacent cell with the lowest load parameter as the target adjacent cell.

The embodiment of the application provides a network blind switching device, which comprises:

the blind switching condition judging module is used for judging whether the blind switching condition is met according to the current network condition of the target terminal;

a data condition judging module, configured to judge whether there are no less than a preset number of sample terminals within a preset range centered on the target terminal if the current network condition reaches a blind handover condition, where the sample terminals include other terminals and the target terminal within the preset range centered on the target terminal;

the device comprises a sample selection module, a sample selection module and a sample selection module, wherein the sample selection module is used for selecting the actual sample terminals with the preset number from the sample terminals if the sample terminals with the number not less than the preset number exist;

the data acquisition module is used for acquiring historical switching data of the actual sample terminal;

a success rate determining module, configured to determine, according to the historical handover data, a handover success rate of a neighboring cell to be selected of the target terminal;

a target adjacent cell determining module, configured to determine a target adjacent cell from the adjacent cells to be selected based on the handover success rate;

and the switching module is used for switching the current cell of the target terminal to the target neighbor cell.

An embodiment of the present application provides a base station device, including: one or more processors; storage means for storing one or more programs; when executed by one or more processors, the one or more programs enable the one or more processors to implement the steps of the network blind handover method as previously described.

The embodiment of the present application provides a computer-readable storage medium, on which a computer program is stored, where the computer program includes program instructions, and when the program instructions are executed, the method for blind handover of a network is implemented.

The network blind switching method provided by the invention realizes that the target adjacent cell with the highest switching success rate is determined according to the historical switching data of the actual sample terminal under the condition that the number of samples is enough, and the target terminal is switched to the adjacent cell with higher success rate, thereby greatly improving the success rate of blind switching and reducing the waste of communication resources.

Drawings

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

Fig. 1 is a diagram illustrating an application scenario of a blind handover method of a network according to an embodiment of the present invention;

fig. 2 is a flowchart of a network blind handover method according to an embodiment of the present invention;

fig. 3 is a flowchart of a network blind handover method according to another embodiment of the present invention;

fig. 4 is a flowchart of a method for determining a target neighboring cell in a network blind handover method according to another embodiment of the present invention;

fig. 5 is a schematic structural diagram of a network blind handover apparatus according to an embodiment of the present invention;

fig. 6 is a schematic structural diagram of a base station device according to an embodiment of the present invention.

Detailed Description

The technical solution in the implementation of the present application is described clearly and completely below with reference to the drawings in the embodiments of the present application. It is to be understood that the specific embodiments described herein are merely illustrative of some, and not restrictive, of the current application. It should be further noted that, based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without any creative effort belong to the protection scope of the present application.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

Furthermore, the terms "first," "second," and the like may be used herein to describe various orientations, actions, steps, components, and the like, but these orientations, actions, steps, or components are not limited by these terms. These terms are only used to distinguish one direction, action, step or component from another direction, action, step or component. The terms "first", "second", etc. are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise. It should be noted that when one portion is referred to as being "secured to" another portion, it may be directly on the other portion or there may be an intervening portion. When a portion is said to be "connected" to another portion, it may be directly connected to the other portion or intervening portions may be present. The terms "vertical," "horizontal," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Before discussing exemplary embodiments in more detail, it should be noted that some exemplary embodiments are described as processes or methods depicted as flowcharts. Although a flowchart may describe the steps as a sequential process, many of the steps can be performed in parallel, concurrently or simultaneously. In addition, the order of the steps may be rearranged. A process may be terminated when its operations are completed, but may have additional steps not included in the figure. A process may correspond to a method, a function, a procedure, a subroutine, a subprogram, etc.

The network blind handover method provided by the application can be applied to the application environment shown in fig. 1. The network blind switching method is applied to a communication system. The communication system includes a terminal 102 and a base station 104. Wherein the terminal 102 and the base station 104 communicate via a network. The target terminal is a terminal 102 in which blind handover occurs; the other terminals refer to all the terminals 102 within a preset range, except the target terminal, and the preset range is an area with the target terminal as the center; the sample terminals are generic to the target terminal and other terminals, i.e. the sample terminals refer to all terminals 102 within a preset range. Judging whether the current network condition of the target terminal reaches a blind switching condition or not according to the current network condition of the target terminal, judging whether sample terminals not less than a preset number exist in a preset range with the target terminal as the center or not when the current network condition reaches the blind switching condition, selecting the actual sample terminals with the preset number from the sample terminals when the sample terminals not less than the preset number exist, acquiring historical switching data of the actual sample terminals, determining the switching success rate of the adjacent cell to be selected according to the historical switching data, determining the target adjacent cell in the adjacent cell to be selected according to the switching success rate, and switching the target terminal to the target adjacent cell. The terminal 102 may be, but is not limited to, various personal computers, laptops, smartphones, tablets, and portable wearable devices, and the base station 104 may be an independent base station or a plurality of base stations.

In an embodiment, as shown in fig. 2, a network blind handover method is provided, and this embodiment is illustrated by applying the method to the base station 104. In this embodiment, the method includes the steps of:

s210, judging whether a blind switching condition is achieved according to the current network condition of the target terminal.

The target terminal is a terminal controlled by the base station for cell switching. The current network condition is used for describing the signal quality of the target terminal in the current cell, and specifically may include various parameters related to the signal; such as the load parameter of the current cell and the demodulation quality parameter of the target terminal. The blind switching condition is a standard for judging whether the target terminal needs to perform blind switching or not; and when the network condition reaches the blind handover condition, the base station controls the target terminal to perform blind handover, otherwise, the base station does not perform blind handover. The blind handover condition may include various conditions such as abnormal load of the current cell, deterioration of demodulation quality of the terminal, and the like.

Specifically, when the target terminal performs network communication through the current cell covered by the base station, the base station may determine the current network status of the target terminal in real time, and the base station may determine whether the current network status of the target terminal meets the blind handover condition according to a preset time interval.

For example, the specific process of determining whether the blind handover condition is met according to the current network condition of the target terminal may include at least one of the following two manners: and judging whether the load amplification of the current cell is greater than a preset amplification or not according to the current network condition, and if so, meeting the blind switching condition. And judging whether the block error rate of the target terminal is increased or not according to the current network condition, and if so, achieving the blind switching condition.

An increase in the block error rate (BLER) indicates deterioration of the demodulation quality of the terminal, which may result in degradation of the communication quality, and a cell handover is required.

The load amplification represents the load parameter increase amplitude, and the preset amplification is a standard for judging that the load parameter increase already causes the need of switching the target terminal to other cells. The increase of the load parameter of the current cell indicates that the number of terminals in charge of the current cell is too large, the communication quality is reduced, and when the increase of the load parameter is more, the target terminal continues to reside in the current cell, and the communication quality is difficult to ensure, so that the target terminal needs to be switched to other cells. Specifically, the base station judges whether the load amplification of the current cell is greater than a preset amplification according to the current network condition, and if so, the blind handover condition is met.

And S220, if the current network state reaches the blind switching condition, judging whether no less than a preset number of sample terminals exist in a preset range taking the target terminal as the center, wherein the sample terminals comprise other terminals and the target terminal in the preset range taking the target terminal as the center.

The preset range is a space standard for determining an area where the sample terminal is located, and specifically, an area formed by taking the target terminal as a circle center and a preset distance (for example, 200 meters) as an outline is the preset range. The preset number is a preset value used for determining whether the number of sample terminals is sufficient (the smaller the preset number is, the more easily the requirement is met), and the preset number can be specifically adjusted according to different situations. An exemplary general set preset number is 10.

The sample terminal is a general name for a designated terminal, and the base station takes historical blind handover data of the sample terminal as an analysis sample when the target terminal is subjected to blind handover. Generally, sample terminals specifically refer to all terminals in a certain area around a target terminal, including the target terminal; the other terminal is a name for distinguishing the target terminal, and indicates all terminals except the target terminal in the area. Whether the sample terminals with the number not less than the preset number exist or not is actually judged whether enough analysis samples exist within the preset distance of the target terminal, the number of the sample terminals is less than the preset number, which indicates that the number of the samples is not enough, and the sample terminals do not have a reference value, and the number of the sample terminals is not less than the preset number, which indicates that the number of the samples meets the requirement, so that the blind switching process of the embodiment can be executed.

Later contents are slightly detailed, the description level is not clear enough, for example, to describe a technical feature A, the related descriptions are put together, and the form is distinguished from the content and B. Secondly, the characteristic interpretation is less clear.

Specifically, after determining that the target terminal needs to perform blind handover, the base station further detects the number of other terminals around the target terminal, so as to determine whether there are enough (not less than a preset number) sample terminals in a preset range of the target terminal.

And S230, if the sample terminals not less than the preset number exist, selecting the actual sample terminals with the preset number from the sample terminals.

The actual sample terminal is a part of the sample terminal. The number of sample terminals in the preset range is uncertain, in this embodiment, under the condition that the number of samples is sufficient, no matter how many sample terminals are, only the sample terminals of the preset number are selected as actual analysis samples, and for the purpose of distinction, the selected sample terminals are referred to as actual sample terminals, and a specific way of determining the actual sample terminals is not limited herein, for example, random selection is performed among the sample terminals. And after determining that the sample terminals with the number not less than the preset number exist in the preset range, the base station selects the sample terminals with the preset number as the terminals in the actual sample.

And S240, acquiring historical switching data of the actual sample terminal.

The historical switching data is switching record data of blind switching of the actual sample terminal in a preset time period (for example, in the last 10 days, in order to avoid large network parameter difference, the preset time period is not too long easily), and is used for analyzing and determining the switching success rate of the to-be-selected neighbor cell.

After determining the terminal in the actual sample, the base station directly obtains historical switching data of the actual sample terminal, and the historical switching data can be stored in the terminal or the base station.

And S250, determining the switching success rate of the adjacent cell to be selected of the target terminal according to the historical switching data.

The neighbor cell to be selected refers to a neighbor cell which can be selected by the terminal as a switching target to complete blind switching. The switching success rate represents the average success rate of switching the actual sample terminal to the adjacent cell to be selected. Specifically, for a cell, the handover success rate is an average value of success rates of blind handover of an actual sample terminal to the cell within a preset time period.

Specifically, the specific process of the handover success rate is as follows: determining a switching record of the adjacent cell to be selected and the corresponding actual sample terminal according to the historical switching data; and determining the average success rate of switching the corresponding actual sample terminal to the adjacent cell to be selected according to the switching record, and taking the average success rate as the switching success rate of the adjacent cell to be selected.

And after obtaining the historical switching data, the base station analyzes the average success rate of switching the actual sample terminal to the neighbor cell to be selected according to the historical switching data to obtain the switching success rate of each neighbor cell to be selected.

And S260, determining a target adjacent cell from the adjacent cells to be selected based on the switching success rate.

The target neighbor cell is the neighbor cell to which the terminal is finally switched, and is generally the cell with the highest switching success rate in the neighbor cells to be selected.

And after determining the switching success rate of each adjacent cell to be selected, the base station selects a proper adjacent cell from the adjacent cells to be selected as a target adjacent cell according to a preset rule and the switching success rate.

S270, switching the current cell of the target terminal to the target adjacent cell.

After the base station determines a target adjacent cell in the adjacent cells to be selected of the target terminal, the base station directly sends a switching instruction to the target terminal, and the switching instruction is used for switching the target terminal to the target adjacent cell.

Preferably, in an alternative embodiment, the actual number of sample terminals may exceed the preset number, and when obtaining the historical handover data, the preset number of sample terminals closest to the target terminal (including the target terminal) are selected as the actual sample terminals, and the historical handover data of the actual sample terminals is further obtained. Illustratively, for a target terminal a, within 200 meters of a square circle of the target terminal, there are 15 other terminals, that is, including the target terminal, 16 terminals coexist within 200 meters of the square circle, and the preset number is 10, then within 15 other terminals, 9 other terminals closest to the target terminal a and the target terminal a are selected as actual sample terminals, and historical switching data of the 10 actual sample terminals is obtained as analysis samples.

In the network blind handover method provided by this embodiment, after the network status of the target terminal reaches the blind handover condition, the base station determines whether there are no less than a preset number of sample terminals in a preset range centered on the target terminal, selects a preset number of actual sample terminals in the sample terminals when there are no less than the preset number of sample terminals, and obtains historical handover data of the actual sample terminals, further determines the handover success rate of the neighboring cell to be selected according to the historical handover data, then selects the target neighboring cell with the highest handover success rate, and finally controls the target terminal to be handed over to the target neighboring cell, so that when the number of samples is sufficient, the target neighboring cell with the highest handover success rate is determined according to the historical handover data of the actual sample terminals, thereby achieving the purpose of handing over the target terminal to the neighboring cell with a higher success rate, and greatly improving the success rate of blind handover, and communication resource waste is reduced.

In another embodiment of the present invention, as shown in fig. 3, a network blind handover method is provided, which further improves part of the content and details on the basis of the previous embodiment, and specifically includes the following steps:

and S310, judging whether a blind switching condition is met according to the current network condition of the target terminal.

And S320, if the current network state reaches the blind switching condition, judging whether no less than a preset number of sample terminals exist in a preset range taking the target terminal as the center.

The sample terminal comprises other terminals and a target terminal within a preset range taking the target terminal as a center.

S330, if the sample terminals not less than the preset number exist, selecting the actual sample terminals with the preset number from the sample terminals, obtaining historical switching data of the actual sample terminals, and determining the switching success rate of the adjacent region to be selected according to the historical switching data.

S340, taking the neighbor cell with the load parameter less than or equal to the preset load value in the neighbor cell to be selected as a first neighbor cell.

The first adjacent cell is an adjacent cell with the load parameter less than or equal to a preset load value in the adjacent cell to be selected. The preset load value is a standard for judging whether the load of the adjacent cell is too high, and can be set according to the actual situation. As can be seen from the blind handover condition example in the previous embodiment, when the load parameter of the current cell is too large, the communication quality of the terminal responsible for the current cell may be affected. On this basis, in order to avoid switching the target terminal to a high-load cell, when selecting the target neighbor cell, a neighbor cell with an excessive load parameter needs to be screened. It should be noted that, since the high-load cell is excluded as a basic function of the base station itself, the method can be applied to the blind handover process without the measurement data of the terminal.

Specifically, after obtaining the historical switching data of the actual sample terminal, the base station further selects the target neighbor cell according to the historical switching data, and the base station eliminates the neighbor cell with the load higher than the preset load value in the neighbor cell to be selected through the basic power of the base station, so as to determine the target neighbor cell in the remaining first neighbor cell.

Optionally, in some cases, the load of the neighboring cell to be selected is higher than the preset load, and at this time, the neighboring cell with the smallest load may be selected as the target neighboring cell from among the neighboring cells to be selected.

S350, determining the switching success rate of each first adjacent cell, and taking the first adjacent cell with the largest switching success rate as a target adjacent cell.

The switching success rate refers to an average success rate of switching the actual sample terminal to the first neighboring cell.

After the base station eliminates the neighboring cells with the overhigh load, the base station sequences or selects other modes for the first neighboring cells based on the switching success rate, and determines the first neighboring cell with the highest switching success rate as the target neighboring cell.

And S360, if the number of the sample terminals is less than the preset number, selecting the neighbor cell with the lowest load parameter from the neighbor cells to be selected as the target neighbor cell.

If there are less than the preset number of sample terminals, which indicates that the number of sample terminals is too small, the target neighboring cell may have a larger deviation based on the analysis and determination of the sample terminals, so that the neighboring cell with the lowest load parameter in the neighboring cells to be selected is selected as the target neighboring cell in this embodiment, and the situation that the switching failure occurs in the neighboring cell with the lowest load parameter is less.

And S370, switching the current cell of the target terminal to the target adjacent cell.

More specifically, in some embodiments, as shown in FIG. 4, step S350 includes S351-358:

s351, dividing the first adjacent cell into an intra-frequency adjacent cell, an inter-frequency adjacent cell and an inter-system adjacent cell according to the network parameters of the first adjacent cell.

The intra-frequency neighboring cell, the inter-frequency neighboring cell, and the inter-system neighboring cell are determined based on LTE (Long Term Evolution) parameters: the intra-frequency refers to the same frequency in the system, the inter-frequency refers to the different frequency in the system, and the inter-system refers to the different system; namely, the adjacent cells are divided into intra-frequency adjacent cells, inter-frequency adjacent cells and inter-system adjacent cells according to three standards of intra-system common frequency, intra-system different frequency and inter-system different frequency. The purpose is as follows: the load of the intra-frequency neighboring cells is generally almost the same, and when the load of the current cell is higher, the intra-frequency neighboring cells are not low, so the blind handover generally selects the target neighboring cells according to the priority sequence of the inter-frequency neighboring cells prior to the inter-system neighboring cells and the inter-system neighboring cells prior to the intra-frequency neighboring cells, and the first neighboring cells are specifically subdivided, so that the success rate of the blind handover is further improved. More specifically, another priority order may also be set in some embodiments: 4G >3G >2G > 5G.

S352, determining the inter-frequency switching success rate of each inter-frequency adjacent cell, and judging whether the inter-frequency adjacent cell with the inter-frequency switching success rate larger than the inter-frequency success rate threshold exists.

The inter-frequency switching success rate is the switching success rate of the inter-frequency adjacent cells, and the inter-frequency switching success rate is the average value of the switching success rates of the actual sample terminal to the corresponding inter-frequency adjacent cells. The inter-frequency success rate threshold is a parameter for screening inter-frequency neighbors (which may be set to 90% as an example). Although the priority order of the inter-frequency neighboring cell, the inter-system neighboring cell, and the intra-frequency neighboring cell is determined, the success rate of the inter-frequency neighboring cell, the inter-system neighboring cell, and the intra-frequency neighboring cell needs to be comprehensively considered. Therefore, the corresponding screening parameters set for the inter-frequency neighboring cell, the inter-system neighboring cell and the intra-frequency neighboring cell are used for screening the neighboring cells with too low switching success rate under the condition of being based on the priority order.

After determining the intra-frequency neighboring cell, the inter-frequency neighboring cell and the inter-system neighboring cell in the first neighboring cell, the base station starts to determine the target neighboring cell according to the priority order of the inter-frequency neighboring cell, the inter-system neighboring cell and the intra-frequency neighboring cell, and firstly screens the inter-frequency neighboring cells with the switching success rate larger than the inter-frequency success rate threshold value in the inter-frequency neighboring cells.

S353, if the inter-frequency neighbor cell with the inter-frequency switching success rate larger than the inter-frequency success rate threshold exists, selecting the inter-frequency neighbor cell with the highest inter-frequency switching success rate as the target neighbor cell.

If an inter-frequency neighboring cell with the inter-frequency handover success rate larger than the inter-frequency success rate threshold exists, it is indicated that a proper inter-frequency neighboring cell exists as a target neighboring cell, and therefore the base station selects the inter-frequency neighboring cell with the highest inter-frequency handover success rate as the target neighboring cell.

S354, if the intra-frequency adjacent cell with the inter-frequency switching success rate larger than the inter-frequency success rate threshold does not exist, determining the inter-system switching success rate of each inter-system adjacent cell, and judging whether the inter-system adjacent cell with the inter-system switching success rate larger than the inter-system success rate threshold exists or not.

The inter-system switching success rate is the switching success rate of the inter-system adjacent cells, and the inter-system switching success rate is the average value of the switching success rates of the actual sample terminal to the corresponding inter-system adjacent cells. The inter-system success rate threshold is a parameter for screening inter-system neighbors (which may be set to 85% as an example). Although the priority order of the inter-frequency neighboring cell, the inter-system neighboring cell, and the intra-frequency neighboring cell is determined, the success rate of the inter-frequency neighboring cell, the inter-system neighboring cell, and the intra-frequency neighboring cell needs to be comprehensively considered. Therefore, the corresponding screening parameters set for the inter-frequency neighboring cell, the inter-system neighboring cell and the intra-frequency neighboring cell are used for screening the neighboring cells with too low switching success rate under the condition of being based on the priority order.

And after determining that the inter-frequency adjacent cell is not suitable as a target adjacent cell, the base station screens the inter-system adjacent cell with the switching success rate larger than the inter-system success rate threshold value in the inter-system adjacent cell.

S355, if the intersystem neighboring cell with the intersystem switching success rate larger than the intersystem success rate threshold exists, selecting the intersystem neighboring cell with the highest intersystem switching success rate as the target neighboring cell.

If the inter-system neighbor cell with the inter-system handover success rate larger than the inter-system success rate threshold exists, it is indicated that a proper inter-system neighbor cell exists as the target neighbor cell, and therefore the base station selects the inter-system neighbor cell with the highest inter-system handover success rate as the target neighbor cell.

S356, if there is no inter-system neighboring cell with the inter-system handover success rate greater than the inter-system success rate threshold, determining the intra-frequency handover power of each intra-frequency neighboring cell, and determining whether there is an intra-frequency neighboring cell with the intra-frequency handover power greater than the intra-frequency handover power threshold.

The power of the intra-frequency switching is the switching success rate of the intra-frequency adjacent regions, and the power of the intra-frequency switching is the average value of the switching success rates of the actual sample terminal to the corresponding intra-frequency adjacent regions. The intra-frequency power threshold is a parameter (which may be set to 95% for example) for screening intra-frequency neighboring cells. Although the priority order of the inter-frequency neighboring cell, the inter-system neighboring cell, and the intra-frequency neighboring cell is determined, the success rate of the inter-frequency neighboring cell, the inter-system neighboring cell, and the intra-frequency neighboring cell needs to be comprehensively considered. Therefore, the corresponding screening parameters set for the inter-frequency neighboring cell, the inter-system neighboring cell and the intra-frequency neighboring cell are used for screening the neighboring cells with too low switching success rate under the condition of being based on the priority order.

And after determining that the inter-system neighbor cell is not suitable as a target neighbor cell, the base station screens the intra-frequency neighbor cell with the switching success rate larger than the intra-frequency success rate threshold value in the intra-frequency neighbor cell.

And S357, if the intra-frequency adjacent cell with the intra-frequency switching power larger than the intra-frequency power threshold exists, selecting the intra-frequency adjacent cell with the highest intra-frequency switching power as the target adjacent cell.

If the intra-frequency adjacent cell with the intra-frequency switching power larger than the intra-frequency power threshold exists, the appropriate intra-frequency adjacent cell exists as the target adjacent cell, and therefore the base station can select the intra-frequency adjacent cell with the highest intra-frequency switching power as the target adjacent cell.

And S358, if the intra-frequency adjacent cell with the intra-frequency switching power larger than the intra-frequency power threshold does not exist, selecting the first adjacent cell with the lowest load parameter as the target adjacent cell.

And after the base station determines that the intra-frequency adjacent cell does not have an adjacent cell suitable for being used as a target adjacent cell after screening is finished, the base station selects the first adjacent cell with the lowest load parameter as the target adjacent cell.

The network blind handover method provided by this embodiment further provides a process of determining a target neighboring cell according to the priority order of inter-frequency neighboring cells, inter-system neighboring cells, and intra-frequency neighboring cells, and further improves the handover success rate of the target neighboring cell on the basis of combining multiple success rate thresholds and a preset load, that is, improves the success rate of blind handover, ensures the communication quality of a terminal, and avoids communication resource waste.

It should be understood that although the various steps in the flow charts of fig. 2-4 are shown in order as indicated by the arrows, the steps are not necessarily performed in order as indicated by the arrows. The steps are not performed in the exact order shown and described, and may be performed in other orders, unless explicitly stated otherwise. Moreover, at least some of the steps in fig. 2-4 may include multiple sub-steps or multiple stages that are not necessarily performed at the same time, but may be performed at different times, and the order of performance of the sub-steps or stages is not necessarily sequential, but may be performed in turn or alternating with other steps or at least some of the sub-steps or stages of other steps.

An embodiment of the present invention provides a network blind handover device, fig. 5 is a schematic structural diagram of the network blind handover device, and as shown in fig. 5, the device includes a blind handover condition determining module 510, a data condition determining module 520, a first target neighboring cell determining module 530, and a handover module 540, where:

a blind handover condition determining module 510, configured to determine whether a blind handover condition is met according to a current network status of the target terminal.

The data condition determining module 520 is configured to determine whether there are no less than a preset number of sample terminals in a preset range centered on the target terminal if the current network condition reaches the blind handover condition, where the sample terminals include other terminals and the target terminal in the preset range centered on the target terminal.

A sample selecting module 530, configured to select a preset number of actual sample terminals from the sample terminals if there are no less than the preset number of sample terminals.

And a data obtaining module 540, configured to obtain historical switching data of the actual sample terminal.

A success rate determining module 550, configured to determine a handover success rate of the neighboring cell to be selected of the target terminal according to the historical handover data.

And a target neighboring cell determining module 560, configured to determine a target neighboring cell from the neighboring cells to be selected based on the handover success rate.

A switching module 570, configured to switch a current cell of the target terminal to a target neighboring cell.

In the network blind handover apparatus provided in this embodiment, after the network status of the target terminal reaches the blind handover condition, the base station determines whether there are no less than a preset number of sample terminals in a preset range centered on the target terminal, selects a preset number of actual sample terminals in the sample terminals when there are no less than the preset number of sample terminals, and obtains historical handover data of the actual sample terminals, further determines the handover success rate of the neighboring cell to be selected according to the historical handover data, then selects the target neighboring cell with the highest handover success rate, and finally controls the target terminal to be handed over to the target neighboring cell, so that when the number of samples is sufficient, the target neighboring cell with the highest handover success rate is determined according to the historical handover data of the actual sample terminals, thereby achieving the purpose of handing over the target terminal to the neighboring cell with a higher success rate, and greatly improving the success rate of blind handover, and communication resource waste is reduced.

More specifically, in some embodiments, the blind handover condition determining module includes:

and the load judgment unit is used for judging whether the load amplification of the current cell is greater than the preset amplification according to the current network condition, and if so, the blind handover condition is achieved.

And the block error rate judging unit is used for judging whether the block error rate is increased or not according to the current network condition, and if so, the blind switching condition is achieved.

More specifically, in some embodiments, the method further comprises:

and the second target neighbor cell determining module is used for selecting the neighbor cell with the lowest load parameter from the neighbor cells to be selected as the target neighbor cell if the number of the sample terminals is less than the preset number.

More specifically, in some embodiments, the first target neighbor determination module 530 includes:

the load screening unit is used for taking the adjacent cell with the load parameter less than or equal to the preset load value in the adjacent cell to be selected as a first adjacent cell;

the switching success rate determining unit is used for determining the switching success rate of each first adjacent cell;

and the target adjacent cell determining unit is used for taking the first adjacent cell with the largest switching success rate as the target adjacent cell.

The handover success rate screening unit includes:

the adjacent cell dividing subunit is used for dividing the first adjacent cell into an intra-frequency adjacent cell, an inter-frequency adjacent cell and an inter-system adjacent cell according to the network parameters of the first adjacent cell;

the intra-frequency switching power screening subunit is used for determining the inter-frequency switching success rate of each inter-frequency adjacent cell, wherein the inter-frequency switching success rate is the average value of the switching success rates of the actual sample terminal to the corresponding inter-frequency adjacent cells, and judging whether the inter-frequency adjacent cells with the inter-frequency switching success rate larger than the inter-frequency success rate threshold exist or not;

the first target neighbor cell determining subunit is used for selecting the inter-frequency neighbor cell with the highest inter-frequency handover success rate as the target neighbor cell if the inter-frequency neighbor cell with the inter-frequency handover success rate larger than the inter-frequency success rate threshold exists;

the inter-frequency switching success rate screening subunit is used for determining the inter-system switching success rate of each inter-system neighboring cell if the intra-frequency neighboring cells with the inter-frequency switching success rate larger than the inter-frequency success rate threshold do not exist, wherein the inter-system switching success rate is the average value of the switching success rates of the actual sample terminals to the corresponding inter-system neighboring cells, and whether the inter-system neighboring cells with the inter-system switching success rates larger than the inter-system success rate threshold exist is judged;

a second target neighboring cell determining subunit, configured to select, if there is an inter-system neighboring cell with an inter-system handover success rate that is greater than an inter-system success rate threshold, an inter-system neighboring cell with a highest inter-system handover success rate as a target neighboring cell;

the inter-system switching success rate screening subunit is used for determining the intra-frequency switching power of each intra-frequency neighboring cell if the inter-system switching success rate is not greater than the inter-system success rate threshold, wherein the intra-frequency switching power is the average value of the switching success rates of the actual sample terminal to the corresponding intra-frequency neighboring cells, and judging whether the intra-frequency neighboring cells with the intra-frequency switching power greater than the intra-frequency power threshold exist or not;

a third target neighboring cell determining subunit, configured to select, if there is an intra-frequency neighboring cell whose intra-frequency switching power is greater than the intra-frequency switching power threshold, the intra-frequency neighboring cell whose intra-frequency switching power is the highest as the target neighboring cell;

and the fourth target neighbor cell determining subunit is used for selecting the first neighbor cell with the lowest load parameter as the target neighbor cell if the intra-frequency neighbor cell with the intra-frequency switching power larger than the intra-frequency power threshold does not exist.

The embodiment provides a network blind switching device, which predicts the expected health condition of a user based on behavior data of the user, determines a character adjusting prop for adjusting the image of a current virtual character by combining the current virtual character of the user, feeds back the change condition of the health condition to the user in a form of sending the character adjusting prop, can enable the user to feel the change condition of the health condition more directly, and can more mobilize the enthusiasm of the user in a form of sending the prop.

For specific limitations of the network blind handover apparatus, reference may be made to the above limitations of the network blind handover method, which is not described herein again. The modules in the network blind switching device can be wholly or partially realized by software, hardware and a combination thereof. The modules may be embedded in a hardware form or independent from a processor in the base station device, or may be stored in a memory in the base station device in a software form, so that the processor calls and executes operations corresponding to the modules.

In one embodiment, a base station device is provided, which may be a server, and its internal structure diagram may be as shown in fig. 6. The base station device includes a processor, a memory, and a network interface connected by a system bus. Wherein the processor of the base station device is configured to provide computing and control capabilities. The memory of the base station device includes a nonvolatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program, and a database. The internal memory provides an environment for the operation of an operating system and computer programs in the non-volatile storage medium. The database of the base station device is used for storing network communication data. The network interface of the base station apparatus is used for communicating with an external terminal through a network connection. The computer program is executed by a processor to implement a network blind handover method.

Those skilled in the art will appreciate that the structure shown in fig. 6 is a block diagram of only a portion of the structure relevant to the present application, and does not constitute a limitation on the base station apparatus to which the present application is applied, and a particular base station apparatus may include more or less components than those shown in the figure, or combine some components, or have a different arrangement of components.

In one embodiment, the network blind handover apparatus provided in the present application may be implemented in the form of a computer program, and the computer program may be executed on the base station device as shown in fig. 6. The memory of the base station device may store various program modules constituting the network blind handover apparatus, such as the condition judgment module 510, the data condition judgment module 520, the first target neighboring cell determination module 530, the data acquisition module 540, the success rate determination module 550, the target neighboring cell determination module 560, and the handover module 570 shown in fig. 5. The computer program formed by the program modules enables the processor to execute the steps of the network blind handover method of the embodiments of the present application described in the present specification.

For example, the base station apparatus shown in fig. 6 may perform step S210 through a blind handover condition determining module in the network blind handover apparatus shown in fig. 5, and determine whether the blind handover condition is reached according to the current network condition of the target terminal. The base station device may execute step S220 through the data condition determining module, and if the current network status meets the blind handover condition, determine whether there are no less than a preset number of sample terminals within a preset range centered on the target terminal, where the sample terminals include other terminals and the target terminal within the preset range centered on the target terminal. The base station device may execute step S230 through the sample selection module, and select a preset number of actual sample terminals from the sample terminals if there are no less than the preset number of sample terminals. The base station device may execute step S240 through the data obtaining module, and obtain historical handover data of the actual sample terminal. The base station device may execute step S250 through the success rate determining module, and determine the handover success rate of the neighboring cell to be selected of the target terminal according to the historical handover data. The base station device may execute step S260 through the target neighboring cell determining module, and determine the target neighboring cell from the neighboring cells to be selected based on the handover success rate. The base station device may execute step S270 through the handover module, and handover the current cell of the target terminal to the target neighboring cell.

In one embodiment, there is provided a base station device comprising a memory storing a computer program and a processor that when executed implements:

if the current network condition reaches the blind switching condition, judging whether no less than a preset number of sample terminals exist in a preset range taking the target terminal as a center, wherein the sample terminals comprise other terminals and the target terminal in the preset range;

acquiring historical switching data of an actual sample terminal;

In one embodiment, the processor, when executing the computer program, further implements: judging whether a blind handover condition is reached according to the current network condition of the target terminal, wherein the blind handover condition comprises at least one of the following two modes:

judging whether the load amplification of the current cell is greater than a preset amplification or not according to the current network condition, if so, reaching a blind switching condition;

and judging whether the block error rate of the target terminal is increased or not according to the current network condition, and if so, achieving the blind switching condition.

In one embodiment, the processor, when executing the computer program, further implements: judging whether there are sample terminals not less than a preset number in a preset range with the target terminal as a center, and further comprising:

and if the number of the sample terminals is less than the preset number, selecting the neighbor cell with the lowest load parameter from the neighbor cells to be selected as the target neighbor cell.

In one embodiment, when the processor executes the computer program, the method further determines the target neighboring cell in the neighboring cells to be selected according to the handover success rate, including:

taking a neighboring cell with the load parameter less than or equal to a preset load value in the neighboring cell to be selected as a first neighboring cell;

determining the switching success rate of each first adjacent cell;

and taking the first adjacent cell with the largest switching success rate as a target adjacent cell.

In one embodiment, the processor, when executing the computer program, further implements: determining the switching success rate of each first adjacent cell, and selecting the first adjacent cell with the largest switching success rate as a target adjacent cell, wherein the method comprises the following steps:

determining the inter-frequency switching success rate of each inter-frequency adjacent cell, wherein the inter-frequency switching success rate is the average value of the switching success rates of the actual sample terminal switched to the corresponding inter-frequency adjacent cells, and judging whether the inter-frequency adjacent cells with the inter-frequency switching success rate larger than the threshold value of the inter-frequency success rate exist or not;

if an inter-frequency neighboring cell with the inter-frequency switching success rate larger than the inter-frequency success rate threshold exists, selecting the inter-frequency neighboring cell with the highest inter-frequency switching success rate as a target neighboring cell;

if no intra-frequency adjacent cell with the inter-frequency switching success rate larger than the inter-frequency success rate threshold exists, determining the inter-system switching success rate of each inter-system adjacent cell, wherein the inter-system switching success rate is the average value of the switching success rates of the actual sample terminal to the corresponding inter-system adjacent cells, and judging whether the inter-system adjacent cell with the inter-system switching success rate larger than the inter-system success rate threshold exists or not;

if the inter-system neighbor cell with the inter-system switching success rate larger than the inter-system success rate threshold exists, selecting the inter-system neighbor cell with the highest inter-system switching success rate as a target neighbor cell;

if no inter-system neighbor cell with the inter-system switching success rate larger than the inter-system success rate threshold exists, determining the intra-frequency switching power of each intra-frequency neighbor cell, wherein the intra-frequency switching power is the average value of the switching success rates of the actual sample terminal to the corresponding intra-frequency neighbor cells, and judging whether the intra-frequency neighbor cell with the intra-frequency switching power larger than the intra-frequency power threshold exists or not;

if the intra-frequency adjacent cell with the intra-frequency switching power larger than the intra-frequency power threshold exists, selecting the intra-frequency adjacent cell with the highest intra-frequency switching power as a target adjacent cell;

and if the intra-frequency adjacent cell with the intra-frequency switching power larger than the intra-frequency power threshold does not exist, selecting the first adjacent cell with the lowest load parameter as the target adjacent cell.

The embodiment provides a method for realizing network blind handover by a base station device, wherein the base station determines whether no less than a preset number of sample terminals exist in a preset range centering on a target terminal after the network condition of the target terminal reaches a blind handover condition, selects a preset number of actual sample terminals from the sample terminals when no less than the preset number of sample terminals exist, acquires historical handover data of the actual sample terminals, further determines the handover success rate of a neighboring cell to be selected according to the historical handover data, selects a target neighboring cell with the highest handover success rate, and finally controls the target terminal to be switched to the target neighboring cell, so that the target neighboring cell with the highest handover success rate is determined according to the historical handover data of the actual sample terminals under the condition that the number of samples is enough, the target terminal is switched to the neighboring cell with the higher handover success rate, and the success rate of blind handover is greatly improved, and communication resource waste is reduced.

In one embodiment, a computer-readable storage medium is provided, having a computer program stored thereon, which when executed by a processor, performs the steps of:

acquiring historical switching data of an actual sample terminal;

Judging whether a blind handover condition is reached according to the current network condition of the target terminal, wherein the blind handover condition comprises at least one of the following two modes:

In one embodiment, the computer program when executed by the processor further implements:

judging whether there are no less than the sample terminals of the preset number in the preset range with the target terminal as the center, and further comprising:

In one embodiment, the computer program when executed by the processor further implements: determining a target adjacent cell from the adjacent cells to be selected based on the switching success rate, wherein the method comprises the following steps:

determining the switching success rate of each first adjacent cell;

In one embodiment, the computer program when executed by the processor further implements: determining the switching success rate of each first adjacent cell, and selecting the first adjacent cell with the largest switching success rate as a target adjacent cell, wherein the method comprises the following steps:

if the frequency-in adjacent cell with the frequency-in switching power larger than the frequency-in power threshold exists, selecting the frequency-in adjacent cell with the highest frequency-in switching power as a target adjacent cell;

The computer-readable storage medium provided by this embodiment can implement a network blind handover method, and implement that, when the number of samples is sufficient, a target neighboring cell with the highest handover success rate is determined according to historical handover data of an actual sample terminal, and the target terminal is handed over to a neighboring cell with a higher success rate, so that the success rate of blind handover is greatly improved, and communication resource waste is reduced.

It will be understood by those skilled in the art that all or part of the processes of the methods of the embodiments described above can be implemented by hardware related to instructions of a computer program, which can be stored in a non-volatile computer-readable storage medium, and when executed, can include the processes of the embodiments of the methods described above. Any reference to memory, database, or other medium used in the embodiments provided herein may include at least one of non-volatile and volatile memory. Non-volatile Memory may include Read-Only Memory (ROM), magnetic tape, floppy disk, flash Memory, optical storage, or the like. Volatile Memory can include Random Access Memory (RAM) or external cache Memory. By way of illustration and not limitation, RAM is available in many forms, such as Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), and the like.

The technical features of the above embodiments can be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the above embodiments are not described, but should be considered as the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above examples only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A network blind handover method is characterized by comprising the following steps:

if the current network state reaches a blind switching condition, judging whether no less than a preset number of sample terminals exist in a preset range taking the target terminal as a center, wherein the sample terminals comprise other terminals in the preset range and the target terminal;

acquiring historical switching data of the actual sample terminal;

switching the current cell of the target terminal to the target neighbor cell;

the determining a target neighbor cell from the neighbor cells to be selected based on the handover success rate includes:

determining the switching success rate of each first adjacent cell;

taking the first adjacent cell with the largest switching success rate as a target adjacent cell;

the taking the first neighboring cell with the largest switching success rate as the target neighboring cell includes:

2. The method according to claim 1, wherein the determining whether the blind handover condition is met according to the current network status of the target terminal includes at least one of the following two ways:

3. The method according to claim 1 or 2, wherein the determining whether there are no less than a preset number of sample terminals within a preset range centered on the target terminal further comprises:

4. The method of claim 1, wherein after determining whether there is an inter-frequency neighboring cell with an inter-frequency handover success rate greater than an inter-frequency success rate threshold, the method further comprises:

5. The method of claim 4, wherein after determining whether there is an intersystem neighboring cell with an intersystem handover success rate greater than an intersystem success rate threshold, the method further comprises:

6. A network blind handover apparatus, comprising:

a data condition judging module, configured to judge whether there are no less than a preset number of sample terminals in a preset range centered on the target terminal if the current network condition reaches a blind handover condition, where the sample terminals include other terminals and the target terminal in the preset range centered on the target terminal;

a switching module, configured to switch a current cell of the target terminal to the target neighboring cell;

the target neighbor cell determining module is specifically configured to use a neighbor cell of which the load parameter is less than or equal to a preset load value in the neighbor cell to be selected as a first neighbor cell; determining the switching success rate of each first adjacent cell; taking the first adjacent cell with the largest switching success rate as a target adjacent cell;

the target neighbor cell determining module is specifically configured to divide the first neighbor cell into an intra-frequency neighbor cell, an inter-frequency neighbor cell, and an inter-system neighbor cell according to the network parameter of the first neighbor cell; determining the inter-frequency switching success rate of each inter-frequency adjacent cell, wherein the inter-frequency switching success rate is the average value of the switching success rates of the actual sample terminal to the corresponding inter-frequency adjacent cells; judging whether an inter-frequency adjacent region with an inter-frequency switching success rate larger than an inter-frequency success rate threshold exists; and if so, selecting the inter-frequency adjacent cell with the highest inter-frequency switching success rate as the target adjacent cell.

7. A base station apparatus, comprising

One or more processors;

storage means for storing one or more programs;

when executed by the one or more processors, enable the one or more processors to implement the network blind handover method of any one of claims 1 to 5.

8. A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, carries out a network blind handover method according to any one of claims 1 to 5.