Mobile communication simulating system

Description: TECHNICAL FIELD [Detailed description of the invention]

【0001】

[Industrial application field]

The present invention relates to a mobile communication simulation method, and more particularly to a mobile communication simulation method for estimating a service area of a mobile communication system.

【0002】

The service areas of the base stations in the mobile communication system are scattered as shown in FIG. 7, but there is no gap between the service areas to ensure that the mobile station can receive the radio waves from the base station. It is desired to eliminate unnecessary overlapping states.

【0003】

[Conventional technology]

In the service area estimation of the conventional mobile communication system, radio wave propagation experiments and manual calculations are performed. This will be described below according to the procedures (1) to (6) shown in FIGS. 8 and 9.

【0004】

(1) First, after displaying the map data stored in the memory such as a CD-ROM on the screen DP, the position of the base station BS is temporarily set on the map of this display screen DP. In this case, the base station BS is one station in the case of a simplified wireless (CRP) system or an MCA system, and is a plurality of stations in the case of a car phone or a mobile phone system. (2) Next, the electric field strength is obtained from the already known elevation data by the radio wave propagation loss theoretical formula (Okumura curve), and the profile, that is, the electric field strength curve corresponding to the distance from the base station BS is obtained from the base station BS. For example, create 12 sheets in 30 ° increments for 360 ° around. (3) Further, the electric field strength profile (dotted line) in (2) above is modified according to the type of antenna to create an electric field strength profile shown by a solid line. (4) Regarding the radio wave propagation loss in (2) above, the electric field strength profile is obtained from the altitude data based on a certain regularity, but the radio wave propagation loss actually changes depending on the terrain and existing buildings. Since there are cases, correction is necessary, and this correction data is created in units of 500m x 500m mesh. (5) Then, the electric field strength profile of the above (2) is corrected according to the correction data of the above (4). (6) Finally, by dropping the electric field strength profile obtained in (5) above on the map, a distribution curve of constant electric field strength centered on the base station BS can be obtained.

【0005】

Depending on whether the service area centered on the base station BS thus obtained covers the desired area or the relationship with the service area of the adjacent base station is normal, the position of the base station is determined. By changing, the most preferable position is finally estimated.

【0006】

[Problems to be Solved by the Invention]

As described above, the conventional mobile communication simulation method has a problem that manual calculation is performed, which requires a lot of time and manpower and lacks accuracy.

【0007】

Therefore, in order to solve these problems, it is an object of the present invention to realize a mobile communication simulation method that does not require manual calculation.

【0008】

[Means for solving problems]

FIG. 1 shows in principle a mobile communication simulation method according to the present invention for achieving the above object, and is a memory 1 storing map data, altitude data, terrain data, and building data, and the map data. Is taken out from the memory 1 as data for one screen, and other data is used as data for each unit mesh. Data processing unit 2 and the map data from the data processing unit 2 are processed and a map is displayed on the display screen 4. The electric field strength profile for each unit mesh is calculated from the computer graphic processing unit 3 for displaying, the input means 5 for inputting the base station data, and the altitude data and the base station data, and the electric field strength profile is used as the topography. A map provided with an electric field strength calculation processing unit 6 for correction calculation based on data and building data, and the electric field strength data obtained by the computer graphic processing unit 3 in the electric field strength calculation processing unit 6 is displayed on the display screen 4. It is characterized in that the display is overwritten on the top and the position of the base station is corrected by the input means 5 based on the display screen 4.

【0009】

Further, in the present invention, the base station data can include data indicating whether the base station has an omni configuration or a sector configuration.

【0010】

Further, in the present invention, the frequency group number may be included in the base station data, and the frequency group number may be corrected as necessary when the position of the base station is corrected.

【0011】

[Action]

In FIG. 1, first, the data processing unit 2 extracts the map data for one required screen from the memory 1, and the computer graphic processing unit 3 displays the map on the display screen 4.

【0012】

Next, when the elevation data, the terrain data, and the building data are taken out from the memory 1 for each unit mesh by the data processing unit 4 and given to the electric field strength calculation processing unit 6, the electric field strength calculation processing unit 6 starts from the input means 5. Based on the input base station data, the electric field strength is calculated using the above-mentioned known radio wave propagation loss theoretical formula (Okumura curve) to obtain the electric field strength profile.

【0013】

The base station data at this time can be assigned an omni configuration, a sector configuration, or a frequency group number as the system configuration.

【0014】

Further, the electric field strength calculation processing unit 6 further corrects the electric field strength data (profile) obtained above with the topographical data and the building data.

【0015】

Then, the electric field strength data corrected in this way is output to the display screen 4 via the computer graphic processing unit 3. At this time, the map displayed at the beginning is displayed on the map without erasing it.

【0016】

This makes it possible to determine whether or not the service area of a base station in a mobile communication system is appropriate, and one base station such as a CRP (simplified wireless portable radio) system or an MCA (multi-channel access) system can be used. In the case of a good system, if the service area of the base station does not cover the desired range, the input means 5 can change the data of the base station to move the position of the base station to the optimum position.

【0017】

Further, in the case of a car phone or a mobile phone system, it is determined whether there is a gap or overlap between the service areas, and the position of the base station is determined as shown in FIG. 6, for example. It will be moved to the optimum position.

【0018】

In this way, in the present invention, the position of the base station can be set accurately without using manual calculation, and the optimum mobile radio system can be designed.

【0019】

[Example]

FIG. 2 shows an embodiment of the mobile communication simulation method according to the present invention. In this embodiment, the memory 1 shown in FIG. 1 stores a magnetic tape 1a storing map data and altitude data. It is composed of a magnetic tape 1b, a magnetic tape 1c that stores topographical data, and a magnetic tape 1d that stores building data.

【0020】

Further, the data processing unit 2 includes a map data processing unit 2a that extracts map data for one screen from the magnetic tape 1a, and an altitude data processing unit 2b that extracts altitude data for each unit mesh (250 m × 250 m) from the magnetic tape 1b. It is composed of a terrain data processing unit 2c that extracts terrain data for each unit mesh from the magnetic tape 1c, and a building data processing unit 2d that extracts building data for each unit mesh from the magnetic tape 1d as building occupancy data.

【0021】

Further, the display screen 4 includes an electric field strength distribution screen 4a, a bird's-eye view screen 4b, and a cross-section screen 4c, and the input means 5 includes a keyboard 5a and a command processing unit 5b. In the figure, 7 is a hard copy output as a figure displayed on the display screen 4.

【0022】

Next, the operation of the embodiment shown in FIG. 2 will be described with reference to FIGS. 3 to 6.

【0023】

Example (for CRP / MCA system) FIG. 3 shows a flowchart for explaining the operation when the embodiment shown in FIG. 2 is applied to a simple wireless mobile phone (CRP) system or a multi-channel access (MAC) system in which one base station is set. It is a thing.

【0024】

First, the map data processing unit 2a in the data processing unit 2 reads out the map data of the magnetic tape 1a from the simulated location (specified by the mesh (10Km × 10Km) number) for one screen (step S1), and the computer graphic processing unit 3 A map (roads, railroads, administrative boundaries, rivers) is displayed on screen 4a via (S2).

【0025】

Next, the position of the base station as base station data is specified from the keyboard 5a (or mouse click) on the map-displayed screen 4a via the command processing unit 5b (S3). As a result, one base station is designated on the screen 4a via the computer graphic processing unit 3.

【0026】

In addition, as other base station data, the base station antenna height, frequency, transmission output, antenna gain, mobile station antenna height, etc. are specified (S4). Note that these base station data may be set in advance as initial values.

【0027】

Next, the elevation data, terrain data, and building data stored in the magnetic tapes 1b to 1d are read out by the processing units 2b to 2d for each unit mesh (250 m × 250 m) and given to the electric field strength calculation processing unit 6. ..

【0028】

The electric field strength calculation processing unit 6 first calculates the electric field strength of the unit mesh based on the altitude data and the position of the base station by the above radio wave propagation loss theoretical formula to obtain the electric field strength profile.

【0029】

Further, by correcting this electric field strength profile based on the above topographical data and building data, the electric field strength profile as shown in FIG. 9 (5) is finally obtained (S5).

【0030】

Then, the calculation result of the electric field strength is displayed (S6). The type of display in this case is the electric field strength distribution screen 4a (color filling for each unit mesh, equal electric field strength curve) as shown in FIG.

【0031】

In addition, as auxiliary functions, there are enlarged display of designated area, bird's-eye view screen 4b (elevation, altitude + electric field strength), cross-section screen 4c (elevation between base station and designated position, electric field strength), electric field strength display of designated point, etc. ..

【0032】

By performing the simulation according to the above procedure and making various corrections to change the position of the base station (S7), it is possible to estimate the optimum position of the base station.

【0033】

Example (in the case of a car phone / mobile phone system) FIG. 5 shows a flowchart for explaining the operation when the embodiment shown in FIG. 2 is applied to a car phone / mobile phone system in which a plurality of base stations are set.

【0034】

As shown in the figure, the flowchart of FIG. 5 is different in that step S3 in the flowchart of FIG. 3 is changed to steps S3A and S3B, which will be described below.

【0035】

That is, as in the embodiment of FIG. 3, after reading the map of the simulated location and displaying the map on the screen (steps S1 and S2), manually (mouse click, latitude) the base station position on the map displayed screen. -Enter longitude) or set automatically (set range, cell radius, number of repeating zones) (S3A). At this time, the system configuration (omni configuration / sector configuration) of the base station is also set (S3B).

【0036】

<Base station position setting method> Explaining the automatic position setting method of the base station here, conventionally, the setting method of the base station position is manually (mouse click, latitude / longitude input) as used in Fig. 3. However, when a large number of base stations are set in a wide range (location of base stations, allocation of frequency group numbers of base stations) in a car phone or the like, a large amount of time and a difference due to a difference in operators may occur.

【0037】

Therefore, the base station is set by the following method. (1) Specify the range for setting the position of the base station. Click the mouse in two places, lower left / upper right. (2) Enter the distance between base stations (cell radius). (3) Specify the number of frequency repetitions. Enter the number of frequency groups in the repeating zone. (4) The position of the base station is set by performing the above processes (1) to (3), and the frequency group number is assigned according to the database (frequency pattern) corresponding to the number of frequency repetitions. (5) Also, select either the omni configuration (omnidirectional characteristics) or the sector configuration (directivity) as the base station system configuration.

【0038】

After designating the base station in this way, specify the base station data (antenna type, antenna tilt angle, etc.) as in the case of Fig. 3 (S4), and calculate the electric field strength from the above data. Also, the interference between each base station (same frequency interference, adjacent frequency interference) is calculated (S5).

【0039】

The calculation results are displayed as a service area diagram and an interference area diagram, and as a function, the electric field strength at the designated point can be displayed (electric field strength for each base station), and the designated area can be expanded (S6).

【0040】

Then, by making various modifications to change the positions of the base stations (S7), it is finally possible to estimate the optimum positions of a plurality of base stations as shown in FIG.

【0041】

[Effect of the invention]

As described above, according to the mobile communication simulation method according to the present invention, map data, elevation data, terrain data, and building data are prepared in a memory, and one or more bases are displayed in a state where the map data is displayed on the screen. The position of the base station is set, and the position of the base station is determined by automatically calculating the electric field strength profile centered on the base station based on the altitude data, the topographical data, and the building data for each unit mesh, if necessary. Since the position of the base station is corrected, the base station can be installed accurately and efficiently for each unit mesh without manual calculation.

[Simple explanation of drawings]

[Figure 1]

It is a block diagram which showed the mobile communication simulation method which concerns on this invention in principle.

[Figure 2]

It is a block diagram which showed the Example of the mobile communication simulation method which concerns on this invention.

[Fig. 3]

It is a flowchart of the service area estimation of the Example which applied the mobile communication simulation method which concerns on this invention to a CRP / MCA system.

[Fig. 4]

It is a figure which showed the electric field strength distribution simulated by the example of FIG.

[Fig. 5]

It is a flowchart of service area estimation at the time of applying the mobile communication simulation method which concerns on this invention to a car phone / mobile phone system.

[Fig. 6]

It is a figure which showed the optimum arrangement of a plurality of base stations simulated by the Example of FIG.

[Fig. 7]

It is a figure which showed the service area by a plurality of base stations.

[Fig. 8]

It is explanatory drawing (the 1) of the conventional example.

[Fig. 9]

It is explanatory drawing (2) of the conventional example.

[Explanation of symbols]

1 memory 2 Data processing unit 3 Computer graphics processing unit 4 Display screen 5 Input means 6 Electric field strength calculation processing unit In the figure, the same reference numerals indicate the same or corresponding parts.