CN113079520B

CN113079520B - Evaluation method for LTE network carrier scheduling capacity reduction cell

Info

Publication number: CN113079520B
Application number: CN202010004164.7A
Authority: CN
Inventors: 刘建强
Original assignee: China Mobile Communications Group Co Ltd; China Mobile Group Guangdong Co Ltd
Current assignee: China Mobile Communications Group Co Ltd; China Mobile Group Guangdong Co Ltd
Priority date: 2020-01-03
Filing date: 2020-01-03
Publication date: 2022-07-01
Anticipated expiration: 2040-01-03
Also published as: CN113079520A

Abstract

The invention relates to an evaluation algorithm for a carrier scheduling capacity reduction cell of an LTE (Long term evolution) network, which comprises the following steps of: identifying load balance degree of a cellular telephone traffic zone formed by a target cell; calculating a weighted average Physical Resource Block (PRB) utilization rate k value of the target cell; and performing composite calculation on the k value in a period of time by using a quarter difference method to obtain a load index with a small target.

Description

Evaluation method for LTE network carrier scheduling capacity reduction cell

Technical Field

The invention relates to an evaluation method of a capacity reduction cell, in particular to an evaluation method for an LTE network carrier scheduling capacity reduction cell.

Background

As for the existing communication technology, when the existing network technology performs carrier dynamic allocation, it is often necessary to reduce the capacity of some idle cells to achieve the purpose of fully utilizing carrier resources.

However, when determining a capacity-reducible cell, it is usually only to count the capacity-class traffic load index of the cell itself to determine whether the capacity-reduction condition is reached, and the load balance between the cell and the adjacent cell and the load condition of the adjacent cell are not evaluated. Thus, current communication technologies run the risk of misreduction, which in turn is more likely to affect network quality and user perception.

Moreover, the statistical method in the prior art ignores the characteristics of user mobility between LTE cells and traffic mobility caused by load balance, so that the capacity of some cells is reduced due to misjudgment of low load caused by traffic imbalance, and further the user perception is influenced.

Disclosure of Invention

The technical problem to be solved by the invention is to provide an evaluation algorithm for LTE network carrier scheduling capacity reduction cells, so as to improve the problem that some cells are misjudged as low load and reduced capacity due to unbalanced telephone traffic when the current network carries out carrier dynamic scheduling.

The technical scheme adopted by the invention for solving the technical problems is as follows: an evaluation algorithm for carrier scheduling reduced cell of LTE network is provided, which comprises the following steps: identifying load balance degree of a cellular telephone traffic zone formed by a target cell; calculating a weighted average Physical Resource (PRB) utilization rate k value of the target cell; and performing composite calculation on the k value in a period of time by using a quarter difference method to obtain a load index with a small target.

Compared with the prior art, the invention has the advantages that:

1. the invention eliminates the cells with unbalanced load by calculating a telephone traffic balance coefficient delta, and further calculates and evaluates the cells with balanced load. Therefore, the misreduction of the traffic unbalance cell caused by the traditional algorithm is avoided, and the network quality and the user perception are not influenced.

2. The invention can reflect the telephone traffic load level in the cellular telephone traffic zone mainly covered by an LTE cell by calculating the utilization rate k value of a weighted average Physical Resource Block (PRB) of the cellular telephone traffic zone, thereby more accurately judging the target cell with real low load, executing carrier scheduling capacity reduction and achieving the maximization of the utilization rate of network resources.

3. According to the invention, through calculating the one-fourth difference k value of the LTE cell, the interference factors such as sudden base station faults, sudden people flow aggregation and the like can be eliminated, and objective index values which accord with the reality are reflected. And calculating an average value by adopting the numerical values on the second and third divisions to obtain a quarter difference k value of each cell, and further judging whether the cells meet the volume reduction condition.

Drawings

Fig. 1 is a process diagram of an evaluation method for a carrier scheduling reduced-capacity cell in an LTE network according to an embodiment of the present invention.

Fig. 2 is a schematic diagram of a cellular traffic zone for an evaluation method of a carrier scheduling reduced-capacity cell in an LTE network according to an embodiment of the present invention.

Detailed Description

The foregoing description shows and describes several preferred embodiments of the invention, but as aforementioned, it is to be understood that the invention is not limited to the forms disclosed herein, but is not to be construed as excluding other embodiments and is capable of use in various other combinations, modifications, and environments and is capable of changes within the scope of the inventive concept as expressed herein, commensurate with the above teachings, or the skill or knowledge of the relevant art. And that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.

Referring to fig. 1, fig. 1 is a process diagram of an evaluation method for a carrier scheduling reduced cell in an LTE network according to the present invention. The following will detail the evaluation method for the carrier scheduling reduced-capacity cell in the LTE network according to the present invention with reference to fig. 1. The implementation method comprises the following steps:

1. and acquiring switching data and Physical Resource Block (PRB) utilization rate of the whole network cell and the neighboring cell day granularity.

In this step, please refer to the data source table in table 1 below. The format of the data field of the index table is as follows. The purpose of this step is to obtain the handover data of each cell and all neighboring cells and the PRB utilization of the whole network cell.

Source cell	Neighbor cell	Number of switching	Percentage of all neighbors	Neighbor cell PRB utilization
					10299-2	10299-3	5964	35.64％	13.52％
10299-2	10299-1	3576	21.37％	11.71％
					10299-2	10293-3	2549	15.23％	32.37％
10299-2	10278-1	1623	9.70％	27.91％
					10299-2	10284-3	974	5.82％	23.64％
10299-2	10293-2	853	5.10％	30.53％
					10299-2	10293-1	538	3.22％	9.05％
10299-2	10278-2	356	2.13％	6.48％
					10299-2	10284-2	227	1.36％	41.81％
10299-2	10278-3	73	0.44％	8.11％

The PRB utilization rate is the maximum value among the PRB utilization rate of the downlink PDSCH, the PRB utilization rate of the downlink PDCCH and the PRB utilization rate of the uplink PUSCH. The switching times shown in table 1 include the number of times of switching in and the number of times of switching out.

2. The 5 front neighbor cells of the cellular traffic zone are determined.

In an LTE network, there is load balancing between cells, which generally exist between different cells of the same site and between adjacent cells having overlapping coverage areas with their peripheries. In any case, the size of the association with the cell can be reflected by the number of times of handover with the cell. In the existing network, there are signal overlapping coverage areas between one cell and 2 other cells of the base station, and between 3 cells in the cell coverage direction, and the number of handovers between these neighboring cells is also large.

In the algorithm model of the present invention, the cell 5(top5) before the number of handovers is used for input calculation, and the area formed by the cells together is defined as a "cellular traffic area". As shown in fig. 2, the number of times of top5 handover of target cell 10229-2 is 10299-3, 10299-1, 10293-3, 10278-1, 10284-3, and the area a formed by these cells is a cellular traffic area. Fig. 2 is a schematic diagram of a cellular traffic area used in the method for evaluating a carrier scheduling reduced cell in an LTE network according to the present invention.

3. A traffic equalization coefficient δ for the cellular traffic region is calculated.

The telephone traffic balance coefficient delta is calculated by adopting a standard deviation algorithm, the standard deviation algorithm is an algorithm for measuring the dispersion degree of a batch of data, and the model can be used for calculating the telephone traffic balance degree of a cellular telephone traffic area.

Through the switching times of each adjacent cell pair obtained in step 1, the PRB utilization rates of 5 adjacent cells including the cell and the top5 switching times, for 6 groups of data, are obtained, and a traffic balancing coefficient δ is calculated, which is as follows:

wherein, μ, represents an average value of 6 groups of data, that is, an average PRB utilization of 6 cells; x is the number of_iIndicating the PRB utilization for each cell. And the smaller δ represents the smaller fluctuation in the data group, the more stable the data, reflecting the more balanced traffic distribution in the cellular traffic zone. When the low-load cell exists, the capacity reduction can be carried out, and the influence on the network is small. The larger the delta, the larger the fluctuation of the data group, the more unstable the data, the more unbalanced the traffic distribution of the cellular traffic area is reflected, and further parameter optimization is needed without suggesting capacity reduction.

For example: there are two sets of data shown in tables 2 and 3. It can be obtained by formula calculation that the delta value of the array 1 is smaller than that of the array 2, namely, the traffic distribution in the array 1 is more balanced than that in the array 2.

By combining actual production and application requirements, δ is 0.05 selected as a judgment demarcation point in the middle line of the invention, and is detailed as follows:

1) and when delta is larger than or equal to 0.05, judging that the telephone traffic in the cellular area is unbalanced, and suggesting that a space for telephone traffic balance and further optimization exists and an inclusion capacity reduction object is not included.

2) And when delta is less than 0.05, judging that the telephone traffic distribution in the cellular area is relatively balanced, and performing the next calculation to screen out the idle cell.

4. The "weighted average PRB utilization k value" of the cellular traffic zone is calculated.

Defining the weighted average PRB utilization k value of a cellular telephone traffic area: as described in step 2, the cellular traffic zone is composed of the own cell and 5 neighboring cells. The weighting coefficients of the cell and the adjacent cell are respectively 50%, the adjacent cell comprises 5 cell samples, and the PRB utilization rate after weighted average is calculated by combining the adjacent cell switching times.

Wherein, the calculation formula is as follows:

wherein the content of the first and second substances,

(1) h1, h2, … and h5 are switching times, wherein n is h1+ h2+ h3+ h4+ h 5;

(2)p_n1，p_n2，…，p_n5the PRB utilization rate of the adjacent region is used;

(3)p_sthe PRB utilization rate of the cell is;

the k value reflects the traffic load level in the cellular traffic area mainly covered by one LTE cell, and the maximum value is 1, which means that the PRB utilization rates of the cell and five neighboring cells of the switching times top5 are all 100%. This is generally not possible due to congestion protection mechanisms in existing network cells. The minimum value of k is 0, which means that the utilization rates of the PRBs in the five adjacent cells of the cell and the switching times top5 are all 0%, which is impossible in the current network unless the cells involved are all zero traffic.

5. And calculating the four-differential k value of the cell.

After the 4 th step, the weighted average PRB utilization k values of all cells with the daily granularity traffic balance coefficient δ <0.05 can be output, but the statistical time period needs to be extended because of the randomness and the volatility of the daily granularity data. In the model, day granularity data of 60 days before the calculation day is adopted, and after the calculation by the steps, each cell can obtain a group of data consisting of 60 k values. Next, the four-differential algorithm is carried out to calculate the log group.

The quartering difference algorithm is also called as a quartering algorithm, and counts from the minimum value of the object array, finds the positions of the 25 th, 50 th and 75 th values, and divides the object array by the three values. After dividing by 3 points, the entire data was equally divided into 4 parts, each containing 25% of the data. Because the telephone traffic of each cell in the actual network has randomness and burstiness, some interference factors are removed by using a four-differential algorithm very suitably, and the index value meeting the actual condition is reflected. In combination with the application, the values in the second and third divisions are used to calculate the average value, and the four-differential k value of each cell is obtained.

6. And outputting a cell list for LTE network carrier scheduling capacity reduction.

After the 5 th step of calculation, the quarter difference k value of the cell with the telephone traffic balance coefficient delta less than 0.05 can be output, the mobile group standard and the practical application are referred, 10% of the quarter difference k value is taken as a low telephone traffic standard threshold capable of reducing capacity, and the cell meeting the threshold condition is taken as a capacity reduction cell and used for carrying out capacity reduction in LTE network carrier scheduling.

Thus, the construction of the volume reduction cell evaluation algorithm model and the output of the volume reduction cell set are completed.

In summary, the present invention proposes a traffic equalization coefficient δ for cellular traffic areas. The traffic balance coefficient delta is calculated by a standard deviation algorithm, and the standard deviation algorithm is an algorithm for measuring the dispersion degree of a batch of data and is used for calculating the traffic balance degree of a cellular traffic area in the model. Wherein, the smaller δ represents the smaller fluctuation in the data group, the more stable the data, the more balanced the traffic distribution of the cellular traffic zone is reflected, and when a low-load cell exists, the capacity reduction can be performed, and the influence on the network is not great. If delta is larger, the fluctuation of the data group is larger, the data is more unstable, the traffic distribution of the cellular traffic area is more unbalanced, and further parameter optimization is needed without suggesting capacity reduction.

In summary, the present invention proposes a "weighted average PRB utilization k value" in a cellular traffic zone. The value of k reflects the traffic load level in the cellular traffic region that is primarily covered by an LTE cell. The cellular telephone traffic area is composed of the local cell and 5 adjacent cells, the weighting coefficients of the local cell and the adjacent cells are respectively 50%, the adjacent cells comprise 5 cell samples, the PRB utilization rate weighting coefficients of the adjacent cells are further determined by combining the adjacent cell switching frequency ratio, and finally the PRB utilization rate after weighted calculation of the local cell is calculated.

In summary, the LTE cell "four-differential k value" is proposed in the present invention. In an actual network, conditions such as burst base station failure, burst people flow aggregation and the like exist, and the telephone traffic of each cell has randomness and burstiness. The interference factors can be eliminated by utilizing a quartering difference algorithm, and objective index values which are in line with the reality are reflected. And combining the application, calculating an average value by adopting the numerical values on the second and third divisions to obtain a four-differential k value of each cell, and further judging whether the cells meet the volume reduction condition.

The following will again summarize the effects achieved by the present invention:

the method has the first effect that the cells with unbalanced loads are eliminated by calculating the telephone traffic balancing coefficient delta, and the cells with balanced loads are further calculated and evaluated, so that the phenomenon that the network quality and the user perception are influenced by mistaken volume reduction of the cells with unbalanced telephone traffic caused by the traditional algorithm is avoided. The close prior art does not have an algorithm in this respect.

And secondly, by calculating the weighted average PRB utilization rate k value of the cellular telephone traffic area, the telephone traffic load level in the cellular telephone traffic area mainly covered by an LTE (Long term evolution) cell can be more scientifically reflected, and the target cell with real low load can be more accurately judged, so that the carrier scheduling capacity reduction is performed, and the maximization of the network resource utilization rate is achieved. The similar prior art is based on the statistics of the telephone traffic of the cell, the algorithm is simple and coarse, and misjudgment often exists.

And thirdly, by calculating the four-differential k value of the LTE cell, the interference factors such as sudden base station faults and sudden people flow aggregation can be eliminated, and the objective index value which accords with the reality is reflected. And calculating an average value by adopting the numerical values on the second and third divisions to obtain a quarter difference k value of each cell, and further judging whether the cells meet the volume reduction condition. The similar prior art is based on averaging traffic over a certain time period in the cell.

In summary, the invention provides an evaluation algorithm for an LTE network carrier scheduling capacity reduction cell, which comprises the steps of firstly identifying the load balance degree of a cellular telephone traffic zone formed by a target cell, secondly calculating the weighted average PRB utilization rate k value of the target cell, and finally carrying out composite calculation on the k value of a period of time by using a four-differential method to obtain a more scientific and reasonable load index of each cell.

In summary, through the application of the evaluation algorithm model provided by the invention, the invention can reduce the influence caused by misjudgment and misreduction, provide carrier resources for carrier scheduling, and finally achieve the purposes of reducing cost, improving efficiency and improving user perception.

Claims

1. An evaluation algorithm for a carrier scheduling reduced cell of an LTE network, comprising the steps of:

acquiring switching data and physical resource block utilization rate of day granularity of a whole network cell and an adjacent cell, determining an adjacent cell 5 before switching times of a cellular telephone traffic zone, and calculating a telephone traffic balance coefficient by using the obtained physical resource block utilization rates of the cell and the adjacent cell 5 before the switching times by adopting a standard deviation algorithm so as to identify the load balance degree of the cellular telephone traffic zone;

after the load balance degree of the cellular telephone traffic zone where the cell is located is identified, further performing parameter optimization on the cellular telephone traffic zone with unbalanced load without capacity reduction, and further performing calculated evaluation on the cell with balanced load as a target cell;

calculating a weighted average physical resource block utilization rate k value of the target cell according to the weighting coefficient, the physical resource block utilization rate of the cell, the physical resource block utilization rate of the adjacent cell and the switching times; and

and performing composite calculation on the k value in a period of time by using a four-differential method to obtain the load index of the target cell.

2. The evaluation algorithm for a carrier scheduling reduced volume cell of an LTE network according to claim 1, wherein the identifying the load balancing level of the cellular traffic zone formed by the target cell further comprises:

and judging whether the traffic balance coefficient is larger than or smaller than a demarcation point value.

3. The evaluation algorithm for an LTE network carrier scheduling reduced volume cell of claim 2, wherein the cellular region traffic imbalance is determined if the traffic equalization coefficient is greater than the demarcation point value, and wherein the cellular region traffic imbalance is determined if the traffic equalization coefficient is less than the demarcation point value.

4. The evaluation algorithm for an LTE network carrier scheduling reduced volume cell of claim 2, wherein the cut-off point value is 0.05.

5. The evaluation algorithm for a carrier scheduling reduced-capacity cell of an LTE network as claimed in claim 3, wherein if the traffic balancing coefficient is greater than the cut-off point value, parameter optimization balancing traffic is performed by an optimizer after the traffic imbalance of the cellular region is judged.

6. The evaluation algorithm for an LTE network carrier scheduling reduced volume cell as claimed in claim 1, wherein the k value is between 0 and 1.

7. The evaluation algorithm for an LTE network carrier scheduling reduced volume cell of claim 1, wherein the value of k represents a traffic load level in a cellular traffic region primarily covered by one LTE cell.

8. The evaluation algorithm for LTE network carrier scheduling reduced capacity cells of claim 1, further comprising the step of outputting a list of cells for LTE network carrier scheduling reduction.