CN100505939C - A method and device for realizing control load balance in a communication system - Google Patents

Abstract

This invention provides a method for controlling load balance including: testing load of each carrier local area periodically, determining carrier local areas which needs to controll the load balance, controlling them in load balance. A device is also disclosed including: a load test module, a module for determining control of the load balance and a load balance module. Frequency switch is carried out to the mobile terminal users with heavy load in the area needing load balance control by a blind switch mode to avoid testing different frequencies with the compression mode at the same time, and reduces times of different frequency switch.

Description

A method and device for realizing control load balance in a communication system

technical field

The invention relates to the technical field of network communication, in particular to a method and device for realizing load balance control in a communication system.

Background technique

In the field of mobile communication technology, CDMA (Code Division Multiple Access) technology has gradually developed and matured. In the initial stage of CDMA technology application, because the traffic volume of the CDMA system using CDMA technology is not large, a carrier frequency often covers a larger area. With the increasing number of CDMA mobile users, it is difficult for one carrier frequency to meet the increasing traffic demand. At this time, a carrier frequency is often added in hot spots to absorb the traffic. In this way, multiple carrier frequencies cover the same area. As shown in Figure 1, in Figure 1, each circle represents a cell, and the coverage of carrier frequency 1 is set to be relatively large, and carrier frequency 1 is represented by f1; the three circles marked with A, B, and C in the figure are located The cell of is a hotspot location area with a large amount of traffic, and the carrier frequency 2 is added to the three cells of A, B, and C respectively, denoted by f2.

In the actual CDMA system, due to factors such as new call access of the CDMA mobile station, changes in the position of the mobile station, changes in the rate of signals sent and received by the mobile station, external interference and changes in the environment, the load of each carrier frequency will randomly occur. Changes, which will lead to unbalanced load. The so-called load balance mainly refers to the load balance between different carrier frequencies in the same area. Unbalanced load will cause some carrier frequency loads to be light and some carrier frequency loads to be heavy. The light load of the carrier frequency will make the resources of the communication system not fully utilized. The heavy load of the carrier frequency will seriously affect the communication quality of the mobile users. Since the CDMA system is a system in which self-interference increases with each other, once the load of the CDMA system reaches a certain level, the performance of the CDMA system will deteriorate rapidly, resulting in the unsatisfied QoS (Quality of Service) of the services in the system, and even a large number of CDMA mobile users dropping calls, etc. Serious consequences.

In order to avoid the load imbalance of different carrier frequencies mentioned above, it is necessary to control the selection and utilization of communication system resources, so as to achieve the load balance of different carrier frequencies and use the communication system resources as effectively as possible. In order to achieve load balance, it is necessary to perform inter-frequency handover for the mobile terminal users in the cell, and switch the mobile station in the carrier frequency with heavy load to the carrier frequency with light load.

In the prior art, the mobile station usually selects a different-frequency cell under the following conditions:

The measurement report reported by the mobile station in the communication state to the mobile communication network equipment indicates that the signal quality of the serving cell has fallen below a certain threshold, and the mobile communication network equipment will notify the mobile station to start inter-frequency measurement. By measuring inter-frequency adjacent cells, mobile The communication network equipment selects a cell with better quality and satisfies the handover judgment conditions, and makes the mobile station switch to this inter-frequency cell by performing an inter-frequency hard handover process.

The process of inter-frequency handover using the prior art will be described below with reference to FIG. 2 . Fig. 2 is a schematic diagram of a carrier frequency cell with different carrier frequencies covering the same area.

In Figure 2, let the carrier frequency cell of f1 in area A be identified as A1, the carrier frequency cell of f1 in area B be identified as B1, the carrier frequency cell of f1 in area C be identified as C1; let the carrier frequency cell of f2 in area A be The cell ID is A2, the carrier cell ID of f2 in area B is B2, and the carrier cell ID of f2 in area C is C2.

If the load of the carrier cell A1 is very heavy, according to the prior art, the mobile station in the communication state in the carrier cell A1 is only located at the edge of the carrier cell A1, that is, the mobile station has measured that the signal quality of the carrier cell A1 has been lower than After a certain threshold, the mobile communication network equipment notifies the mobile station to start inter-frequency measurement. If the mobile station is a single receiver, then it is necessary to start the compressed mode to perform different-frequency measurements on the adjacent cells of different frequencies, including the carrier frequency cells A2, B2, and C2, and report the measurement results to the mobile communication network equipment. The device selects the carrier frequency cell with better quality and meets the inter-frequency handover conditions as the target cell of the inter-frequency handover, and then performs the inter-frequency hard handover process. If the load of the carrier frequency cell A1 is very heavy, for the mobile terminal users in the center of the carrier frequency cell A1, the prior art cannot switch them to the carrier frequency f2. Obviously, the purpose of absorbing the traffic of the carrier frequency f2 and lightening the load of the carrier frequency f1 cannot be fully realized by using the existing technology.

From the description of the above technical solution, it can be seen that the mobile station in the communication state will only perform inter-frequency measurement when it is at the edge of the serving cell, that is, after measuring that the pilot signal quality of the serving cell is lower than a certain threshold. The hard handover process switches to another carrier frequency. When the mobile station is located in the center of the serving cell, that is, when the measured pilot signal quality of the serving cell is higher than a certain threshold, no matter how heavy the load of the serving cell is, it will never perform inter-frequency measurement and will not switch to another carrier. frequency. Therefore, the existing technology cannot really play the role of load balancing.

The compression mode must be used when a single receiver performs inter-frequency measurement, and the use of the compression mode will cause adverse effects on the performance of the CDMA system. The CDMA communication system uses codewords to distinguish different mobile terminal users. Mobile terminal users can continuously receive signals of a certain frequency in time, and they no longer have "idle time slots" like in TDMA (Time Division Multiple Access). To measure different frequencies, therefore, for a mobile station with only one receiver, to realize the measurement of signals of different frequencies, the compressed mode must be used to form a transmission "gap" in the wireless frame for a period of time through techniques such as code punching, During this interval, the base station does not transmit any data to the mobile station, and the mobile station can switch its radio frequency receiver to the target frequency to be monitored and measure the target frequency. Code punching and other technologies reduce the redundancy of data. According to the principle of information theory, in order to make up for this loss, the data after punching must be transmitted at a higher power. Since CDMA is a system in which self-interference increases with each other, the increase in power affects performance of the CDMA system.

Contents of the invention

The purpose of the present invention is to provide a method and device for controlling load balance in a communication system, which uses mobile communication network equipment to actively and regularly detect the load of each carrier frequency cell to truly realize the load balance control of each carrier frequency cell, thereby achieving The purpose of improving the performance of the mobile communication system.

In order to achieve the above object, the present invention provides a method for implementing load balancing control in a communication system, including:

a. Regularly detect the load of each carrier frequency cell;

b. Determine the heaviest-loaded and lightest-loaded carrier frequency cells according to the detection results, the load in the heaviest-loaded carrier-frequency cell is greater than the predetermined load absolute threshold and the load difference between the heaviest-loaded and the lightest-loaded carrier frequency cell is greater than the predetermined load difference When the value threshold is determined, the carrier frequency cells with the heaviest load and the lightest load are determined as the carrier frequency cells that need to control load balancing;

c. Perform load balancing control on the carrier frequency cells that need to be controlled for load balancing.

The step a includes: regularly detecting the load of each carrier frequency cell according to the load detection timer.

The step b includes: determining the heaviest and lightest loaded carrier cell according to the load detection results of each carrier frequency cell; Whether the frequency cell is a carrier frequency cell that needs to control load balancing;

If the load of the carrier frequency cell with the heaviest load is greater than the predetermined load absolute threshold and the load difference between the heaviest load and the lightest load carrier frequency cell is greater than the predetermined load difference threshold, the heaviest load and the lightest load The frequency cell is a carrier frequency cell that needs to control load balancing;

Otherwise, the carrier frequency cell with the heaviest load and the carrier frequency cell with the lightest load are carrier frequency cells that do not need to control load balancing.

Described step c comprises:

c1. Start counting the number of switching retries;

c2. Determine the mobile terminal users in the heaviest-loaded carrier-frequency cell that need to be handed over to the lightest-loaded carrier-frequency cell;

c3. Performing inter-frequency handover for the mobile terminal user;

c4, judging whether the inter-frequency handover is successful;

If the inter-frequency switching is successful, this load balancing control is ended, and the load detection timer is reset;

If the inter-frequency handover is unsuccessful, the count value of the number of handover retries is incremented, and it is judged whether the count value of the number of handover retries is greater than the number of handover retries;

If not greater than the number of switching retries, return to step c2;

If it is greater than the number of handover retries, the current load balancing control is ended, and the load detection timer is reset.

Described step c2 comprises:

Obtain the load of mobile terminal users in each communication state in the most heavily loaded carrier frequency cell;

Obtain the average number of the load difference between the load of the heaviest-loaded carrier frequency cell and the load of the lightest-loaded carrier frequency cell;

Among the mobile terminal users whose load is not greater than the average number, the mobile terminal user with the highest load is taken as the mobile terminal user requiring inter-frequency handover.

If another method is used, said step c2 includes:

Obtain the service normalization factor of the mobile terminal users in each communication state in the most heavily loaded carrier frequency cell;

Among the mobile terminal users whose service normalization factor is not greater than the service normalization factor threshold, the mobile terminal user with the largest service normalization factor is regarded as the mobile terminal user who needs to perform inter-frequency handover.

The business normalization factor K of the mobile terminal user is:

K=10 ^(yx)/10 ×p×R _{current service} /R _{standard service} ;

Among them: p is the activation factor; x is the target value of the SIR of the standard service; y is the target value of the SIR of the current service; R _{current service} is the data rate of the current service; R _{standard service} is the data rate of the standard service.

The present invention also provides a device for controlling load balancing in a communication system, including:

Load detection module: regularly detect the load of each carrier frequency cell, and transmit the detected load of each carrier frequency cell to the determination control load balancing module;

Determine and control the load balancing module: determine the heaviest and lightest loaded carrier frequency cells according to the load of each carrier frequency cell transmitted by the load detection module, and the load of the heaviest loaded carrier frequency cell is greater than the predetermined load absolute threshold and the load is the lowest When the load difference between the heavy and lightest-loaded carrier cells is greater than the predetermined load difference threshold, determine the heaviest-loaded and lightest-loaded carrier cells as carrier cells that need to be controlled for load balancing, and notify the load balancing module;

Load balancing module: perform load balancing control on the mobile terminal users in the carrier frequency cell that needs load balancing control according to the information notified by the determining and controlling load balancing module.

The load balancing module includes:

Determine the mobile terminal user submodule: determine the mobile terminal users who need to perform inter-frequency handover in the carrier frequency cell that needs load balancing control, and notify the inter-frequency handover submodule that needs to perform inter-frequency handover. Mobile terminal users;

Inter-frequency handover sub-module: performs inter-frequency handover for mobile terminal users notified by the sub-module for determining mobile terminal users that need to perform inter-frequency handover.

It can be seen from the above technical solutions of the present invention that the present invention regularly and actively detects the load of each carrier frequency cell through the mobile communication network equipment, sets the load absolute threshold and the load difference threshold to determine the carrier frequency cell that needs to be load balanced, Mobile terminal users do not need to perform inter-frequency measurement, and the mobile terminal users in the carrier frequency cell with heavy load and requiring load balancing control are handed over to the inter-frequency cell with light load through blind handover, so that when the carrier frequency cell When the load is heavy, even if the mobile terminal user is in the center of the serving cell, it will be handed over to a light-load inter-frequency cell; A factorial method is used to select mobile terminal users for inter-frequency handover, which minimizes the number of inter-frequency handovers and ensures that the load of light-loaded carrier frequency cells will not increase sharply after inter-frequency handovers. Real, high-efficiency The purpose of controlling load balance is achieved; moreover, the technical solution of the present invention avoids the problem of high power transmission caused by mobile terminal users using compressed mode for inter-frequency measurement; thereby achieving the purpose of improving the performance of the communication system.

Description of drawings

FIG. 1 is a schematic diagram of a multi-carrier frequency coverage area in a communication system;

Fig. 2 is a schematic diagram of carrier frequency cells covered by different carrier frequencies in the same area in the communication system;

Fig. 3 is the flowchart of the control load balancing of the present invention;

Fig. 4 is a device for controlling load balancing of the present invention.

Detailed ways

The core idea of the present invention is that the mobile communication network equipment regularly and actively detects the load of each carrier frequency cell, and determines the carrier frequency cell that is overloaded or lightly loaded and needs to be controlled for load balancing according to the detection results, and controls the load for the said need The balanced cell performs load balancing control.

The mobile communication network equipment can realize timing and active detection of the load of each carrier frequency cell through the timer, such as setting the load detection timer, and the mobile communication network equipment will detect the load of each carrier frequency cell when the load detection timer expires.

After the mobile communication device detects the load of each carrier frequency cell, it needs to determine the cell for load control. The implementation method is: setting the load absolute threshold and the load difference threshold. The purpose of setting the load absolute threshold is to judge whether the load status of the carrier frequency cell is light or heavy. If the loads of different carrier frequency cells are all light loads, there is no need to perform load adjustment. Since the load of each carrier frequency cell fluctuates and changes at any time, setting the load difference threshold can avoid the fluctuation of the load of different carrier frequency cells within a small range and cause the load between different carrier frequencies to be adjusted back and forth.

Select a carrier frequency cell with the heaviest load and a carrier frequency cell with the lightest load from the detected carrier frequency cells. If the loads of the two selected carrier cells meet the following two conditions at the same time, it is determined that the two carrier cells are carrier cells that need to be controlled for load balancing.

Condition 1: The load of the carrier frequency cell with the heaviest load needs to be greater than the absolute load threshold.

Condition 2: The difference between the load of the cell with the heaviest load and the load of the cell with the lightest load needs to be greater than the load difference threshold.

If the two conditions cannot be satisfied at the same time, it is determined that the selected two carrier frequency cells do not need to perform load balancing control, the load balancing control is completed this time, and the load detection timer is reset.

If these two conditions are satisfied at the same time, it is determined that the above-mentioned two selected carrier frequency cells are carrier frequency cells requiring load balancing control. It is necessary to perform inter-frequency handover for mobile terminal users in the most heavily loaded carrier frequency cell. The method that the present invention carries out the inter-frequency handover to the mobile terminal user in the heaviest carrier frequency sub-district is the blind handover method, namely selects the mobile terminal user in the heaviest carrier frequency sub-district, these selected mobile terminal users do not need For inter-frequency measurement, the mobile communication network equipment directly issues an inter-frequency handover command to notify the selected mobile terminal users to switch to an inter-frequency cell, so that even if the mobile terminal user in the carrier frequency cell with the heaviest load is in the carrier frequency cell may also be switched to the inter-frequency cell with the lightest load. Therefore, the purpose of controlling loads of different-frequency cells to achieve balance can be fully realized. The blind switching mode provided by the present invention avoids the problem of high-power transmission caused by enabling the compressed mode to perform inter-frequency measurement when the mobile terminal user is a single receiver.

In order to prevent the load of the lightest-loaded carrier frequency cell from being sharply increased after inter-frequency handover, the present invention adopts two methods in selecting mobile terminal users for inter-frequency handover:

The first method is: first calculate the load difference between the load of the heaviest-loaded carrier-frequency cell and the load of the lightest-loaded carrier-frequency cell, and set the calculation result as Ldiff; set n of the heaviest-loaded carrier-frequency cells in communication The mobile communication terminal users in the state, respectively occupy the loads L1, L2, ..., Ln, among these mobile terminal users, select the mobile terminal user whose load is not greater than Ldiff/2 and has the largest load as the mobile terminal for inter-frequency handover user. The purpose of using mobile terminal users whose load is not greater than Ldiff/2 as inter-frequency handover is to balance the loads of the two cells as much as possible, and avoid the lightest-loaded carrier frequency cell due to inter-frequency handover of mobile terminal users. The load increased sharply. The mobile terminal user whose load is not greater than Ldiff/2 and has the largest load is used as the mobile terminal user of the inter-frequency handover, which minimizes the number of inter-frequency handovers and efficiently realizes the load balance control of the carrier frequency cell.

In order to better achieve the purpose of controlling the load balance between different frequency cells, the number of handover retries can be set. count. If the inter-frequency handover for the selected mobile terminal user is successful, the current load balancing control ends. The load detection timer is reset, and when it times out, the load of each carrier frequency cell is detected again, and the next load balancing control is performed. If the inter-frequency handover for the selected mobile terminal user is unsuccessful, the count value of the handover retry times is incremented. Judging whether the count value is greater than the number of handover retries, if not, reselecting other mobile terminal users from the mobile terminal users whose load is not greater than Ldiff/2 and has the largest load according to the above method. If it is greater than the number of switching retries, the current load balancing control ends. The load detection timer is reset, and when it times out, the load of each carrier frequency cell is detected again, and the next load balancing control is performed.

The method provided by the present invention is applicable to the situation that the mobile communication network equipment can calculate and determine the load of each mobile terminal user, if the mobile communication network equipment cannot determine the load of each mobile terminal user, then the following introduction provided by the present invention can be used Another mobile terminal user method for selecting inter-frequency handover.

The second method is: set the service normalization factor threshold as Kmax, set n mobile communication terminal users in the communication state in the most heavily loaded carrier frequency cell, and calculate and determine the service normalization of each mobile terminal user respectively Kilfactors are K1, K2, .., Kn. Among these mobile terminal users, a mobile terminal user whose service normalization factor is not greater than Kmax and has the largest service normalization factor is selected as a mobile terminal user for inter-frequency handover. The mobile terminal users whose business normalization factor is not greater than Kmax are used as the mobile terminal users of inter-frequency handover, in order to balance the load of the two cells as much as possible, and avoid the lightest load due to the inter-frequency handover of mobile terminal users The load of the frequency cell increases sharply. The mobile terminal users with the service normalization factor not greater than Kmax and the largest service normalization factor are used as mobile terminal users for inter-frequency handover, which minimizes the number of inter-frequency handovers and efficiently realizes the carrier frequency cell. Load balancing control.

Similarly, in order to better achieve the purpose of controlling the load balance between different-frequency cells, the number of handover retries can be set. The number of trials is counted. If the inter-frequency handover for the selected mobile terminal user is successful, the current load balancing control ends. The load detection timer is reset, and when it times out, the load of each carrier frequency cell is detected again, and the next load balancing control is performed. If the inter-frequency handover for the selected mobile terminal user is unsuccessful, the count value of the handover retry times is incremented. Judging whether the count value is greater than the number of handover retries, if not, reselecting other mobile terminal users from the mobile terminal users whose service normalization factor is not greater than Kmax and has the largest service normalization factor according to the above method. If it is greater than the number of switching retries, the current load balancing control ends. The load detection timer is reset, and when it times out, the load of each carrier frequency cell is detected again, and the next load balancing control is performed.

The service normalization factor in the above method indicates the ratio of the CIR of the current service to the CIR of the standard service, that is, how many standard services the current service is equivalent to.

The standard service can be selected by the mobile communication network equipment as a standard service at a certain rate. For example, the mobile communication network equipment selects a voice service with a rate of 12.2 kbps as a standard service. Suppose the SIR target value of standard service Eb/No is x dB, the data rate is R _{standard service} kbps; the SIR Eb/No target value of current service is y dB, and the data rate is R _{current service} kbps.

Because the signal-to-interference ratio Eb/No has the following relationship with the carrier-to-interference ratio Ec/No: Eb/No=W/R×Ec/No; where W is the channel bandwidth and R is the data rate, so there are:

(Ec/No) _{standard business} =(Eb/No) _{standard business} ×R _{standard business} /W=10 ^×/10 ×R _{standard business} /W;

(Ec/No) _{current business} =(Eb/No) _{current business} ×R _{current business} /W=10 ^y/10 ×R _{current business} /W;

The business normalization factor K is:

K=(Ec/No) _{current business} /(Ec/No) _{standard business} =10 ^(yx)/10 ×R _{current business} /R _{standard business} ;

If the activation factor of the current business is considered, the business normalization factor expression is:

K=10 ^(yx)/10 ×p×R _{current service} /R _{standard service} ;

Among them, p is the activation factor, which is due to the use of the voice activation detection technology, the change of the data service due to the change of the service source, etc., which will lead to discontinuous transmission of the channel power. We refer to the ratio of the time of transmitting power on the channel to the time occupied by the channel as the activation factor of the channel.

Since a mobile terminal user may occupy multiple transmission channels during communication, the service normalization factor of this user is the sum of normalization factors of all channels.

The present invention will be described in further detail below in conjunction with accompanying drawing 2 .

Set the load absolute threshold as T _absolute , the load difference threshold as T _relative , and the switching retry times as 3. In Figure 2, when the load detection timer expires, the mobile communication network equipment detects the loads of the carrier frequency cells A1, A2, B1, B2, C1, and C2, and determines by comparison that the carrier frequency cell with the heaviest load is A1, and the carrier frequency cell with the highest load is A1. The light carrier frequency cell is A2. If the load of the carrier cell A1 is set to be greater than the load absolute threshold T _absolute and the load difference between the carrier cell A1 and the carrier cell A2 is greater than the load difference threshold T _relative , then the mobile communication network device determines that the carrier cell A1 and the carrier cell The load of the cell A2 is subjected to load balancing control.

Start counting the number of handover retries.

The mobile communication network equipment selects the mobile terminal users who need inter-frequency handover among the mobile terminal users in the communication state of the carrier frequency cell A1, and the selected mobile terminal users must satisfy that their load is not greater than (the load of the carrier frequency cell A1-carrier frequency The load of cell A2)/2 load of mobile terminal users has the largest load, and the selected mobile terminal users do not need to perform inter-frequency measurement on inter-frequency adjacent cells A2, B2, and C2, and the network device directly sends a hard handover command to notify the selected mobile terminal user The terminal user switches to the inter-frequency cell A2.

The mobile communication network device judges whether the inter-frequency handover is successful, and if the inter-frequency handover is successful, the current load balancing control is ended and the load detection timer is reset. If the inter-frequency handover is unsuccessful, the count value of the number of handover retries is incremented, and another mobile terminal user for inter-frequency handover is reselected according to the above method. When the count value of the switching retry times is 4, the current load balancing control is ended, and the load detection timer is reset.

The flow chart of the implementation method for controlling load balance in the communication system provided by the present invention is shown in FIG. 3 . In FIG. 3 , step 300 starts the load balancing control of the present invention. Go to step 310, set the load absolute threshold, the load difference threshold, the number of switching retries, and reset the load detection timer. Go to step 320, check the load detection timer, go to step 330, judge whether the load detection timer is overtime, if not, go to step 320, continue to check the load detection timer. In step 330, if the load detection timer expires, go to step 340, the mobile communication network equipment detects the load of each carrier frequency cell, and determines the heaviest loaded carrier frequency cell and the lightest loaded carrier frequency cell in each carrier frequency cell.

Go to step 350, judge whether the load of the heaviest carrier frequency cell is greater than the load absolute threshold, if not greater than the load absolute threshold, illustrate that the load of this load heaviest carrier frequency cell does not need to carry out load balancing control, to step 395, load detection Timer reset, go to step 320.

In step 350, if the load of the heaviest-loaded carrier cell is greater than the absolute load threshold, it indicates that the load of the heaviest-loaded carrier cell has reached the set heavy load level, and the load of the heaviest-loaded carrier cell needs to be adjusted. Load balancing control. To step 360, it is judged whether the load difference between the load of the heaviest carrier frequency cell and the load of the lightest carrier frequency cell is greater than the load difference threshold, if the difference is not greater than the load difference threshold, then it is impossible to avoid the The fluctuation of the load within a small range causes the load between different carrier frequencies to adjust back and forth, so it is not necessary to switch the mobile terminal users of other carrier frequency cells to this carrier frequency cell, and go to step 395 to reset the load detection timer , to step 320.

In step 360, if the difference is greater than the load difference threshold, the mobile terminal users of other carrier frequency cells can be handed over to the carrier frequency cell, and in step 370, start to determine the heaviest load and the lightest load carrier frequency The load in the cell performs load balancing control, and starts counting the number of load switching times.

Go to step 380, determine the mobile terminal user who needs to perform different frequency handover according to the load or business normalization factor of the mobile terminal user in the communication state described above, and go to step 390, perform different frequency switching for the determined mobile terminal user Handover, and switch it to the lightest-loaded carrier frequency cell.

Go to step 391, judge whether the inter-frequency handover is successful, if the inter-frequency handover is not successful, go to step 392, the count value of the handover retry times is incremented by 1, and go to step 393, judge whether the count value is greater than the handover retry times, if If it is greater than the number of switching retries, go to step 394 , the current load balancing control ends, go to step 395 , reset the load detection timer, go to step 320 .

In step 393, if it is not greater than the number of handover retries, go to step 380 to determine other mobile terminal users who need to perform inter-frequency handover according to the load of the mobile terminal user in the communication state or the business normalization factor method described above.

In step 391 , if the inter-frequency handover is successful, go to step 394 , the current load balancing control ends, go to step 395 , reset the load detection timer, go to step 320 .

The present invention also provides a device for controlling load balancing. As shown in FIG. 4 , the device includes: a load detection module 410 , a load balancing module 420 for determining control, and a load balancing module 430 . The function of the load balancing module 430 is realized by the mobile terminal user determination submodule 431 and the inter-frequency switching submodule 432 .

The load detection module 410 regularly detects the load of each carrier frequency cell according to the load detection timer, and transmits the detected load of each carrier frequency cell to the determining and controlling load balancing module 420 .

Determine and control the load balancing module 420 to receive the load of each carrier frequency cell transmitted by the load detection module 410, and determine the heaviest load carrier frequency cell and the lightest load carrier frequency cell according to the load of each carrier frequency cell, and at the same time according to the predetermined load absolute Threshold and load difference threshold determine whether the most heavily loaded carrier frequency cell and the lightest loaded carrier frequency cell are carrier frequency cells that need to perform load balancing control, and notify the mobile terminal user submodule 431 to determine the carrier frequency cells that need to perform load balancing control , start counting the number of switching retries. If the detected carrier frequency cells with the heaviest load and the lightest load do not need to perform load balancing control, the load detection module 410 is notified to reset the load detection timer.

Determine the mobile terminal user sub-module 431 in the carrier frequency cell that requires load balancing control, determine the mobile terminal user that needs to perform inter-frequency handover according to the load or service normalization factor of the mobile terminal user in the communication state described above , and notify the inter-frequency handover submodule 432 of the mobile terminal users who need to perform inter-frequency handover.

The inter-frequency handover sub-module 432 performs inter-frequency handover on the mobile terminal users who need to perform inter-frequency handover notified by the mobile terminal user sub-module 431 . When the mobile terminal user's inter-frequency handover is unsuccessful, the notification determines that the count value of the handover retry times in the control load balancing module 420 is incremented by 1, and the determination control load balance module 420 judges whether the count value is greater than the handover retry times, if greater than Switch the number of retries and determine the control load balance module 420 to notify the load detection module 410 to reset the load detection timer. If it is not greater than the number of handover retries, the determination control load balance module 420 notifies the mobile terminal user submodule 431 to determine that in the carrier frequency cell that needs to perform load balancing control, according to the load or the load of the mobile terminal user in the communication state introduced above, The service normalization factor again determines other mobile terminal users who need to perform inter-frequency handover.

While the invention has been described by way of example, those skilled in the art will appreciate that there are many variations and changes to the invention without departing from the spirit of the invention, and it is intended that such variations and changes be covered by the appended claims.

Claims (9)

1, a kind of controlling load balance is characterized in that comprising:

A, timing detect the load of each carrier cell;

B, determine the underloading of the heaviest and load of load sub-district frequently according to testing result, greater than the absolute thresholding of predetermined load and load is the heaviest and the difference of the underloading load of sub-district frequently of load during greater than the predetermined load difference threshold, the underloading of the heaviest and load needing to be defined as the carrier cell of control load balance in the sub-district frequently with described load in the load of the most heavily loaded frequency of load sub-district;

C, switch the described carrier cell of control load balance that needs is carried out load balance control by mobile phone users being carried out alien frequencies.

2, a kind of controlling load balance as claimed in claim 1 is characterized in that described step a comprises:

Regularly detect the load of each carrier cell according to the load detecting timer.

3, a kind of controlling load balance as claimed in claim 1 is characterized in that described step b comprises:

Determine the underloading of the heaviest and load of load sub-district frequently according to the load detecting result of described each carrier cell;

According to the absolute thresholding of predetermined load, predetermined load difference threshold judge the underloading of the heaviest and load of load frequently the sub-district whether be the carrier cell of needs control load balance;

If the difference of the load of the most heavily loaded frequency of load sub-district underloading load of sub-district frequently of the heaviest and load greater than the absolute thresholding of described predetermined load and load is greater than described predetermined load difference threshold, the underloading of the heaviest and load of described load sub-district frequently is the carrier cell that needs the control load balance;

Otherwise, the underloading of described load the most heavily loaded frequency sub-district and load frequently the sub-district for not needing the carrier cell of control load balance.

4, a kind of controlling load balance as claimed in claim 3 is characterized in that described step c comprises:

C1, begin be to switch the number of retries metering;

C2, need in the most heavily loaded frequency of the load sub-district to determine alien frequencies to switch to the underloading of the load mobile phone users in the sub-district frequently;

C3, described mobile phone users is carried out alien frequencies switch;

C4, judge that described alien frequencies switches whether success;

If the alien frequencies handover success finishes this load balance control, the load detecting timer resets;

If alien frequencies switches unsuccessful, the metering value of switching number of retries increases progressively, and judges that whether the metering value of switching number of retries is greater than switching number of retries;

If be not more than the switching number of retries, return step c2;

If greater than switching number of retries, finish this load balance control, the load detecting timer resets.

5, a kind of controlling load balance as claimed in claim 4 is characterized in that described step c2 comprises:

Obtain the load of the mobile phone users of each communication state in the most heavily loaded frequency of the load sub-district;

Obtain the underloading of the load of the most heavily loaded frequency of load sub-district and the load average of the load difference of sub-district frequently;

The mobile phone users that load is not more than load maximum in the mobile phone users of described average carries out the mobile phone users that alien frequencies switches as needs.

6, a kind of controlling load balance as claimed in claim 4 is characterized in that described step c2 comprises:

Obtain the professional normalization factor of the mobile phone users of each communication state in the most heavily loaded frequency of the load sub-district;

The mobile phone users that professional normalization factor is not more than professional normalization factor maximum in the mobile phone users of professional normalization factor thresholding carries out the mobile phone users that alien frequencies switches as needs.

7, a kind of controlling load balance as claimed in claim 6 is characterized in that the professional normalization factor K of described mobile phone users is:

K=10 ^(y-x)/10* p * R _{Current business}/ R _{Benchmark service}

Wherein: p is an activity factor; X is the desired value of benchmark service signal interference ratio; Y is the desired value of current business signal interference ratio; R _{Current business}Data rate for current business; R _{Benchmark service}Data rate for benchmark service.

8, the device of control load balance in a kind of communication system is characterized in that comprising:

Load detecting module: regularly detect the load of each carrier cell, and the load of detected each carrier cell is transferred to definite control load balance module;

Determine the control load balance module: the underloading of the heaviest and load of load sub-district is frequently determined in the load of each carrier cell that transmission comes according to described load detecting module, in the load of the most heavily loaded frequency of load sub-district greater than the absolute thresholding of predetermined load and load is the heaviest and the difference of the underloading load of sub-district frequently of load during greater than the predetermined load difference threshold, the underloading of the heaviest and load of described load needing to be defined as the carrier cell of control load balance and notification payload balance module in the sub-district frequently;

Load balance module: needs are carried out mobile phone users in the carrier cell of load balance control according to the information of described definite control load balance module notice and carry out alien frequencies and switch, to carry out load balance control.

9, the device of control load balance in a kind of communication system as claimed in claim 8 is characterized in that described load balance module comprises:

Determine the mobile phone users submodule: determine that described needs carry out the mobile phone users that needs to carry out the alien frequencies switching in the carrier cell of load balance control, and notice alien frequencies switching submodule need be carried out the mobile phone users that alien frequencies switches;

Alien frequencies switching submodule: the needs of described definite mobile phone users submodule notice are carried out mobile phone users that alien frequencies switches carry out alien frequencies and switch.

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