JP2014060687A - Area design support device, area design support method, and computer program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To calculate a maximum value of a traffic amount which can be accommodated by a radio communication system whose service area is a target area where an installation place of a base station, base station parameter, and traffic distribution data are given, under the condition that the base station arrangement and the base station parameter are not changed and a traffic distribution tendency shown by the traffic distribution data is kept.SOLUTION: An area design support device comprises a traffic accommodation amount calculation unit 15 for calculating a maximum value of a traffic accommodation amount in a target area by solving a predetermined optimization problem for maximizing an objective function value "an increase amount of traffic distribution" using an objective function which is an increase amount to uniformly increase the traffic distribution in the target area, under the constraint condition that each base station in the target area accommodates traffic at a traffic rate equal to or more than a desired traffic rate.

Description

  The present invention relates to an area design support apparatus, an area design support method, and a computer program related to a wireless communication system.

  In a mobile communication system represented by, for example, a mobile phone as a wireless communication system, an examination is made as to whether a required communication quality can be satisfied for an area (target area) that is an area design target.

  In the area design, the target area is generally divided into divided areas having a certain size. Next, using the base station location data, base station information such as the antenna tilt angle of the base station, topographic data and building data of the target area, etc., the received signal strength and C / I in each divided area (Carrier signal power to interference power ratio; one of the indicators of radio wave interference) is estimated, and it is confirmed that the estimated value is equal to or greater than the required value. In addition, using traffic distribution data of communication traffic (hereinafter simply referred to as traffic) in the target area, it is confirmed that the traffic accommodation rate is equal to or higher than a required value. As a result of the area design, when there is a divided area where the communication quality does not meet the required value, or when the traffic coverage of the target area does not meet the desired value, the tilt angle of the base station antenna is changed, etc. Base station parameter adjustments are made.

  Also, in the area design, when the base station installation location is undecided, the base station that satisfies the required values of the received signal strength, C / I, and traffic capacity in each divided area with the minimum number of base stations. The installation location of is calculated. For example, in Patent Document 1, as a base station installation design method including calculation of a base station installation location, when a target area and traffic distribution data of the target area are given, arrangement of base stations that satisfy a desired traffic accommodation rate And a method for setting parameters. Further, the traffic capacity obtained when all the base stations installed in the target area allocate all the radio resources is set as the equipment capacity of the radio communication system having the target area as the service area.

JP 2004-201269 A

  However, in the conventional area design technology described above, when a base station installation location, base station parameters, and traffic distribution data are given in a target area, a wireless communication system that uses the target area as a service area is The maximum traffic volume that can be accommodated cannot be calculated while maintaining the tendency of the traffic distribution indicated by the traffic distribution data with the station arrangement and the base station parameters as they are.

  The present invention has been made in consideration of such circumstances, and when the base station installation location, base station parameters, and traffic distribution data are given in the target area, the base station arrangement and the base station parameters are determined. It is an object of the present invention to calculate the maximum amount of traffic that can be accommodated by a wireless communication system that uses the target area as a service area while maintaining the traffic distribution trend indicated by the traffic distribution data.

  In order to solve the above-described problem, an area design support device according to the present invention is an area design support device for a wireless communication system in which an increase amount that uniformly increases a traffic distribution in a target area is an objective function, and the target area The target area is obtained by solving a predetermined optimization problem for maximizing the objective function value “increase in traffic distribution” under the constraint condition that traffic exceeding a desired traffic capacity is accommodated in each base station in the network. The traffic capacity calculation unit for calculating the maximum value of the traffic capacity is provided.

  In the area design support device according to the present invention, in the target area, an input unit that inputs a base station installation location, base station parameters, and traffic distribution data, and the traffic distribution for each divided area obtained by dividing the target area. A target area setting unit that sets the traffic amount indicated by the data, and calculates a propagation loss value from each base station to each divided area in the target area, and based on the propagation loss value, in each divided area from each base station A radio characteristic calculator that calculates received signal power, and the traffic capacity calculator is configured to determine a CINR (Carrier to Carrier) of each divided area based on a received signal power for each set of a base station and a divided area in the target area. Interference and Noise power Ratio) is calculated, and the throughput in each divided area is calculated based on the CINR. Solving the optimization problem with throughput in traffic volume and the divided areas of the area, characterized in that.

  In the area design support apparatus according to the present invention, the optimization problem includes that each base station in the target area uses a plurality of carrier frequencies.

  In the area design support device according to the present invention, the optimization problem has a traffic increase rate correction value corresponding to a land use classification of a divided area obtained by dividing the target area.

  In the area design support apparatus according to the present invention, the optimization problem includes a condition for each terminal type for which a usable carrier frequency is limited.

  In the area design support apparatus according to the present invention, the optimization problem includes, as a condition, a ratio of terminals using each carrier frequency with respect to types of terminals that can use a plurality of carrier frequencies.

  An area design support method according to the present invention is an area design support method for a wireless communication system, wherein an increase amount that uniformly increases a traffic distribution in a target area is used as an objective function, and is desired in each base station in the target area. The maximum value of the traffic capacity in the target area is obtained by solving a predetermined optimization problem that maximizes the objective function value “amount of increase in traffic distribution” under the restriction condition of accommodating traffic exceeding the traffic capacity of Is calculated.

  A computer program according to the present invention is a computer program for performing area design support processing of a wireless communication system, and uses an increase amount that uniformly increases a traffic distribution in a target area as an objective function, Constraining the traffic in the target area by solving a predetermined optimization problem that maximizes the objective function value “amount of increase in traffic distribution” with the constraint that the base station accommodates traffic that exceeds the desired traffic accommodation rate. It is a computer program for causing a computer to realize a traffic capacity calculation function for calculating the maximum value of the amount.

  According to the present invention, in a target area, when a base station installation location, base station parameters, and traffic distribution data are given, the traffic distribution indicated by the traffic distribution data remains the base station arrangement and base station parameters. It is possible to calculate the maximum value of the traffic volume that can be accommodated by the wireless communication system having the target area as the service area.

It is a block diagram which shows the structural example of the area design assistance apparatus 1 which concerns on one Embodiment of this invention. It is a flowchart which shows the process sequence of the area design assistance apparatus 1 shown in FIG. It is a conceptual diagram of the map data which divided | segmented the target area which concerns on one Embodiment of this invention into a division area. It is a flowchart which shows the procedure of the traffic capacity | capacitance calculation process (step S2) shown in FIG. It is explanatory drawing for demonstrating Example 1 of this invention. It is explanatory drawing for demonstrating Example 1 of this invention. It is explanatory drawing for demonstrating Example 1 of this invention. It is explanatory drawing for demonstrating Example 2 of this invention. It is explanatory drawing for demonstrating Example 2 of this invention. It is explanatory drawing for demonstrating Example 3 of this invention.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this embodiment, an orthogonal frequency division multiple access (OFDMA) mobile communication system will be described as an example of a wireless communication system.

  FIG. 1 is a block diagram illustrating a configuration example of an area design support apparatus 1 according to an embodiment of the present invention. In FIG. 1, the area design support apparatus 1 includes an input unit 11, a target area setting unit 12, a wireless characteristic calculation unit 13, a storage unit 14, a traffic capacity calculation unit 15, an output unit 16, and a database unit 17. The input unit 11 inputs various input data. The target area setting unit 12 sets a target area.

  The wireless characteristic calculation unit 13 calculates wireless characteristic data in the target area. The storage unit 14 stores various data. The traffic capacity calculator 15 calculates the maximum traffic capacity in the target area. The output unit 16 outputs various data.

  The database unit 17 stores various data. The data stored in the database unit 17 includes map data for the target area and traffic distribution data for the target area. The traffic distribution data is data indicating the amount of traffic at each point in the target area. For example, the traffic distribution data indicates the amount of traffic at each point at the time of peak communication demand in the target area. Or traffic distribution data shows the traffic amount in each point at the time of the off-peak of the communication demand in an object area.

  Further, the data stored in the database unit 17 may include building data indicating the outer shape of a building in the target area and altitude data indicating the altitude of each point in the target area. Building data and altitude data are used when building height and presence / absence of visibility are used when calculating wireless characteristic data in the target area.

  The database unit 17 may be connected to the area design support device 1 by communication via a communication network such as the Internet.

  The input unit 11 includes an input device such as a keyboard and a mouse as an input device, a reading device that reads data from a recording medium, and the like. The output unit 16 includes a display device such as a liquid crystal display device, a recording device for a recording medium, and a printing device as an output device. These input devices and output devices may be directly connected to the area design support device 1 or may be connected via a communication line.

  In the configuration example of FIG. 1, the area design support device 1 includes the database unit 17, but data acquired from the database unit 17 may be input from the input unit 11. In this case, the database unit 17 is not necessary.

  FIG. 2 is a flowchart showing a processing procedure of the area design support apparatus 1 shown in FIG. The overall operation of the area design support apparatus 1 will be described with reference to FIG.

(Step S1: Initial setting process)
In the initial setting process, setting of a target area and calculation of wireless characteristic data in the target area are performed. The initial setting process will be described below.

  The input unit 11 includes target area range data for specifying a range of the target area, traffic capacity data indicating a traffic capacity ratio in the target area, base station arrangement data indicating an installation location of each base station in the target area, Base station parameter data indicating base station parameters (transmission power, noise power, antenna height, antenna gain, antenna pattern, etc.) of the base station, use frequency band data indicating the use frequency band of the mobile communication system, and the size of the divided area Input data such as divided area size data to be shown, propagation loss model data to show a propagation loss model formula, and the like are input. These input data are stored in the storage unit 14. Examples of propagation loss model equations include ray tracing, Walfisch and Ikegami models.

  The target area setting unit 12 acquires map data in a range indicated by the target area range data from the database unit 17. Next, the target area setting unit 12 divides the target area into divided areas having a size indicated by the divided area size data in the map data of the target area. FIG. 3 shows a conceptual diagram of map data obtained by dividing the target area into divided areas. In FIG. 3, the target area (a range surrounded by a solid line) is divided into divided areas (a range surrounded by a broken line) having a certain size.

  Next, the target area setting unit 12 acquires the traffic distribution data of the target area from the database unit 17. Next, the target area setting unit 12 collects the traffic distribution data of the target area for each divided area. For example, for each divided area, the traffic amount at each point in the divided area is summed, and the sum is used as the traffic amount of the divided area. The divided area position data indicating the position of each divided area and the traffic amount of each divided area are stored in the storage unit 14. The traffic amount is combined with the throughput and unit described later. This is to make it applicable to the optimization problem described later. For example, “bit / second” is used as a unit of traffic volume and throughput.

  The wireless characteristic calculation unit 13 calculates a propagation loss value from each base station to each divided area in the target area. In this propagation loss calculation, with respect to the propagation loss model expression indicated by the propagation loss model data, the installation location of each base station indicated by the base station arrangement data, the base station parameters of each base station indicated by the base station parameter data, and the divided areas The position of each divided area indicated by the position data is applied.

  Next, the radio characteristic calculation unit 13 calculates received signal power in each divided area from each base station based on the propagation loss value. The received signal power is stored in the storage unit 14 for each set of base station and divided area.

  The above is the description of the initial setting process.

(Step S2: Traffic capacity calculation processing)
The traffic capacity calculator 15 calculates the maximum traffic capacity in the target area. Details of the traffic capacity calculation processing will be described later.

(Step S3: Output processing)
The output unit 16 outputs the result of the traffic capacity calculation process.

  FIG. 4 is a flowchart showing a procedure of the traffic capacity calculation process (step S2) shown in FIG. The operation of the traffic capacity calculator 15 will be described with reference to FIG. The traffic capacity calculation unit 15 uses the data stored in the storage unit 14 to perform traffic capacity calculation processing.

(Step S21)
The traffic capacity calculation unit 15 obtains a serving area of each base station in the target area. First, the traffic capacity calculator 15 obtains, as a serving base station, a base station having the maximum received signal power in each divided area, based on the received signal power for each set of base station and divided area. Next, for each base station in the target area, the traffic capacity calculation unit 15 sets all the divided areas that are serving base stations as the serving area of the base station.

(Step S22)
The traffic capacity calculator 15 calculates the CINR (Carrier to Interference and Noise power Ratio) of each divided area in the target area. In this CINR calculation, for each divided area, the CINR is calculated using the received signal power from the serving base station as a desired signal and the received signal power from a base station other than the serving base station as interference power. Further, the value indicated by the base station parameter data is used for the noise power.

(Step S23)
The traffic capacity calculator 15 calculates the throughput of each divided area in the target area. In this throughput calculation, the CINR of each divided area obtained in step S22 is applied to, for example, the Shannon capacity formula. Further, the value indicated by the use frequency band data is used as the frequency bandwidth. The throughput of a certain divided area obtained in step S23 is the throughput obtained when all the radio resources that can be allocated per second are allocated to the divided area.

(Step S24)
The traffic capacity calculator 15 calculates the maximum traffic capacity in the target area. Hereinafter, a method for calculating the maximum traffic capacity will be described with reference to examples.

  Unless the environment of the target area changes significantly, for example, unless a new commercial facility is constructed, the geographical trend of the traffic distribution of the target area is considered to be preserved. For this reason, an increase amount x that uniformly increases the traffic distribution in the target area is defined. In each embodiment, an increase amount x of the traffic distribution is used as an objective function, and it is assumed that each base station accommodates traffic exceeding a desired traffic accommodation rate, and the objective function value “increase amount x of traffic distribution” is set as a constraint condition. Set optimization problems to maximize.

  In Example 1, the carrier frequency that can be used by each base station in the target area is one band. The constraint condition of the optimization problem is that “the base station installed in the target area accommodates the traffic accommodation rate γ (where 0 <γ ≦ 1) or more in its own serving area”. This optimization problem is expressed by equation (1).

Where i is an identifier representing a divided area, j is an identifier representing a base station installed in the target area, a _i is the traffic volume of the divided area i in the traffic distribution data, α _i is the throughput in the divided area i, {BS _j } Represents a set of divided areas with the base station j (BS _j ) serving as a serving base station.

  The traffic capacity calculator 15 calculates the maximum value of the traffic distribution increase amount x by solving the optimization problem of the equation (1).

  The traffic capacity calculation unit 15 can use known software for solving the optimization problem. For example, the traffic capacity calculation unit 15 may be configured using software called “solver”.

  5 to 7 are explanatory diagrams for explaining the first embodiment. In the example of FIGS. 5 to 7, two base stations (BS_A, BS_B) are installed in a target area composed of 16 divided areas. In FIG. 5 to FIG. 7, the shaded area is the serving area of the base station (BS_A), and the other divided areas are serving areas of the base station (BS_B).

  FIG. 5 is an example of the traffic distribution in the target area, and shows the traffic amount of each divided area. FIG. 6 shows an example of the throughput of the divided area, and the throughput of each divided area is shown. Here, it is assumed that the traffic accommodation rate γ is 1.

  By solving the optimization problem of Expression (1) using the traffic distribution of FIG. 5 and the throughput of FIG. 6, the maximum value of the traffic distribution increase amount x is calculated as “1.264”. The maximum value “150.416” of the traffic volume that can be accommodated is calculated by multiplying the total value “119” of FIG. 5 by the maximum value “1.264” of the traffic distribution increase amount x. The traffic distribution at this time is obtained as shown in FIG. The traffic distribution of FIG. 7 preserves the same geographical tendency as the original traffic distribution (FIG. 5). Thereby, the maximum value “150.416” of the traffic volume that can be accommodated was calculated while maintaining the traffic distribution trend of FIG. 5 while maintaining the base station arrangement and base station parameters in the target area.

  In Example 2, the carrier frequencies that can be used by each base station in the target area are two bands. Here, it is assumed that at least the first carrier frequency covers the entire target area. The constraint condition of the optimization problem is that “the base station installed in the target area accommodates the traffic accommodation rate γ (where 0 <γ ≦ 1) or more in its own serving area”. The optimization problem in the second embodiment is expressed by equation (2).

However, BIN represents a divided area. I * is a set of divided areas i covered by both the first carrier frequency and the second carrier frequency. I # is a set of divided areas i covered only by the first carrier frequency. a ¹ _i is the amount of traffic accommodated by the first carrier frequency in the divided area i. “A _i x−a ¹ _i ” is the traffic amount accommodated at the second carrier frequency in the divided area i. α ¹ _i is a throughput obtained by the first carrier frequency in the divided area i. α ² _i is a throughput obtained by the second carrier frequency in the divided area i.

  The traffic capacity calculation unit 15 calculates the maximum value of the traffic distribution increase amount x by solving the optimization problem of Expression (2).

  8 and 9 are explanatory diagrams for explaining the second embodiment. In the example of FIGS. 8 and 9, as in FIGS. 5 to 7, two base stations (BS_A, BS_B) are installed in the target area composed of 16 divided areas. It is a serving area for the station (BS_A), and the other divided areas are serving areas for the base station (BS_B). Further, it is assumed that the traffic distribution in the target area is the same as that in FIG.

  FIG. 8 shows the throughput in each divided area according to the first carrier frequency. FIG. 9 shows the throughput in each divided area according to the second carrier frequency. By solving the optimization problem of Expression (2) using the traffic distribution of FIG. 5 and the throughputs of FIGS. 8 and 9, the maximum value of the traffic distribution increase amount x is calculated as “2.275”. . The maximum value “270.725” of the traffic volume that can be accommodated is calculated by multiplying the maximum value “2.275” of the increase amount x of the traffic distribution by the total traffic volume “119” of FIG. Thus, as in the first embodiment, the maximum value “270.725” of the traffic volume that can be accommodated is calculated while maintaining the traffic distribution trend of FIG. 5 while maintaining the base station arrangement and base station parameters in the target area. It was.

  In addition, even when the carrier frequency that can be used by each base station in the target area is three or more bands, it can be set as an optimization problem by applying in the same manner.

  In the third embodiment, the carrier frequency that can be used by each base station in the target area is two bands. Here, it is assumed that at least the first carrier frequency covers the entire target area. In the third embodiment, it is assumed that the increase rate of the traffic distribution varies depending on the land use classification of the target area. Here, the land use classification indicates the use status of land such as commercial facilities, residential areas, and rivers. As for the prospect of future traffic increase, generally, a large increase in traffic volume can be expected in commercial facilities, but the traffic volume in rivers does not change significantly. For this reason, in the third embodiment, the increase amount x that uniformly increases the traffic distribution in the target area is multiplied by the increase rate according to the predetermined land use category, thereby reflecting the difference in the traffic increase rate according to the land use category. Let

  The constraint condition of the optimization problem is that “the base station installed in the target area accommodates the traffic accommodation rate γ (where 0 <γ ≦ 1) or more in its own serving area”. The optimization problem in the third embodiment is expressed by equation (3).

However, g _i is a correction value of the traffic increase rate corresponding to the land use classification of the divided areas i, is given in advance.

  FIG. 10 is an explanatory diagram for explaining the third embodiment. In the example of FIG. 10, as in FIGS. 5 to 9, two base stations (BS_A, BS_B) are installed in a target area composed of 16 divided areas, and the hatched divided areas are base stations (BS_A ) And the other divided areas are serving areas of the base station (BS_B). Further, it is assumed that the traffic distribution in the target area is the same as that in FIG. Further, it is assumed that the throughput in each divided area by the first carrier frequency is the same as that in FIG. 8, and the throughput in each divided area by the second carrier frequency is the same as that in FIG.

Figure 10 shows the correction value g _i of traffic increase rate based on the land use classification of each divided area i. By solving the optimization problem of Equation (3) using the traffic distribution of FIG. 5, the throughputs of FIGS. 8 and 9, and the traffic increase rate correction value of FIG. 10, the maximum value of the traffic distribution increase amount x is obtained. Calculated as “1.603”. Multiplying the traffic distribution amount of each divided area i in FIG. 5 by the maximum value “1.603” of the increase amount x of the traffic distribution and the correction value g _i of the traffic increase rate based on the land use classification of each divided area i, By calculating the sum of the products, the maximum traffic volume “230” that can be accommodated is calculated.

  When a plurality of carrier frequencies are used in a mobile communication system, not all terminals are compatible with all carrier frequencies, and the usable carrier frequencies may be limited depending on the type of terminal. Thus, in the fourth embodiment, it is assumed that the carrier frequencies that can be used by each base station in the target area are two bands, and there are three types of terminals, A, B, and C. Here, it is assumed that at least the first carrier frequency covers the entire target area. The shares of terminal types A, B, and C are assumed to be “0.4” for terminal type A, “0.3” for terminal type B, and “0.3” for terminal type C, respectively. Further, it is assumed that the terminal type A can use only the first carrier frequency. It is assumed that terminal type B can use only the second carrier frequency. It is assumed that the terminal type C can use both the first carrier frequency and the second carrier frequency. Also, it is assumed that only certain terminal types are not concentrated in the target area.

  The constraint condition of the optimization problem is that “the base station installed in the target area accommodates the traffic accommodation rate γ (where 0 <γ ≦ 1) or more in its own serving area”. The optimization problem in the fourth embodiment is expressed by equation (4).

However, s ¹ _c is the ratio of terminals connected to the base station using the first carrier frequency among terminals of terminal type C. s ² _c is the ratio of terminals connected to the base station using the second carrier frequency among terminals of terminal type C.

  As a specific example of Example 4, the traffic distribution in the target area is the same as in FIG. 5, the throughput in each divided area by the first carrier frequency is the same as that in FIG. 8, and in each divided area by the second carrier frequency. Assume that the throughput is the same as in FIG. By solving the optimization problem of Expression (4) using the traffic distribution of FIG. 5 and the throughputs of FIGS. 8 and 9, the maximum value of the traffic distribution increase amount x is calculated as “2.275”. The maximum value “270.725” of the traffic volume that can be accommodated is calculated by multiplying the maximum value “2.275” of the increase amount x of the traffic distribution by the total traffic volume “119” of FIG.

  The above is the description of the embodiment of the method for calculating the maximum traffic capacity.

  As shown in FIG. 7, the output unit 16 may output output data on a map showing a traffic distribution to which the maximum traffic volume that can be accommodated is applied.

  According to the above-described embodiment, when the installation location of the base station, the base station parameters, and the traffic distribution data are given in the target area, the traffic distribution data indicates the base station arrangement and the base station parameters as they are. The maximum value of the traffic volume that can be accommodated can be calculated while maintaining the traffic distribution trend. As a result, for example, it is possible to easily study how much the traffic volume in the target area can be handled with the current setting of the base station.

  As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the specific structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.

Further, a program for realizing the functions of the area design support apparatus 1 shown in FIG. 1 is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system and executed. The area design support process may be performed. Here, the “computer system” may include an OS and hardware such as peripheral devices.
Further, the “computer system” includes a homepage providing environment (or display environment) if a WWW system is used.
“Computer-readable recording medium” refers to a flexible disk, a magneto-optical disk, a ROM, a writable nonvolatile memory such as a flash memory, a portable medium such as a DVD (Digital Versatile Disk), and a built-in computer system. A storage device such as a hard disk.

Further, the “computer-readable recording medium” means a volatile memory (for example, DRAM (Dynamic DRAM) in a computer system that becomes a server or a client when a program is transmitted through a network such as the Internet or a communication line such as a telephone line. Random Access Memory)), etc., which hold programs for a certain period of time.
The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.
The program may be for realizing a part of the functions described above. Furthermore, what can implement | achieve the function mentioned above in combination with the program already recorded on the computer system, and what is called a difference file (difference program) may be sufficient.

DESCRIPTION OF SYMBOLS 1 ... Area design assistance apparatus, 11 ... Input part, 12 ... Target area setting part, 13 ... Radio | wireless characteristic calculation part, 14 ... Memory | storage part, 15 ... Traffic capacity calculation part, 16 ... Output part, 17 ... Database part

Claims (8)

In an area design support device for a wireless communication system,
The objective function value “traffic distribution” is defined as an objective function that is an increase amount that uniformly increases the traffic distribution in the target area, and that each base station in the target area accommodates traffic that exceeds a desired traffic capacity. A traffic capacity calculation unit that calculates a maximum value of the traffic capacity in the target area by solving a predetermined optimization problem that maximizes the "increase amount".
An area design support device characterized by comprising: In the target area, an input unit for inputting a base station installation location, base station parameters, and traffic distribution data;
A target area setting unit that sets a traffic amount indicated by the traffic distribution data for each divided area obtained by dividing the target area;
A radio characteristic calculation unit that calculates a propagation loss value from each base station to each divided area in the target area, and calculates received signal power in each divided area from each base station based on the propagation loss value; ,
The traffic capacity calculator is
The CINR of each divided area is calculated based on the received signal power for each set of the base station and the divided area in the target area, the throughput in each divided area is calculated based on the CINR, and the traffic amount of the divided area and the Solve the optimization problem using the throughput in the divided areas,
The area design support apparatus according to claim 1.   The area design support apparatus according to claim 1, wherein the optimization problem includes a condition that each base station in the target area uses a plurality of carrier frequencies.   The area design support according to any one of claims 1 to 3, wherein the optimization problem has a correction value of a traffic increase rate corresponding to a land use classification of a divided area obtained by dividing the target area. apparatus.   The area design support apparatus according to claim 3, wherein the optimization problem includes a share for each type of terminal for which a usable carrier frequency is limited.   The area design support apparatus according to claim 5, wherein the optimization problem includes, as a condition, a ratio of terminals that use each carrier frequency with respect to types of terminals that can use a plurality of carrier frequencies. An area design support method for a wireless communication system, comprising:
The objective function value “traffic distribution” is defined as an objective function that is an increase amount that uniformly increases the traffic distribution in the target area, and that each base station in the target area accommodates traffic that exceeds a desired traffic capacity. Calculating a maximum value of traffic capacity in the target area by solving a predetermined optimization problem that maximizes the `` increase amount ''.
An area design support method characterized by that. A computer program for performing area design support processing of a wireless communication system,
The objective function value “traffic distribution” is defined as an objective function that is an increase amount that uniformly increases the traffic distribution in the target area, and that each base station in the target area accommodates traffic that exceeds a desired traffic capacity. A traffic capacity calculation function for calculating the maximum value of the traffic capacity in the target area by solving a predetermined optimization problem that maximizes the "increase amount".
A computer program for realizing a computer.

Images