Radio wave propagation simulation device, radio wave propagation simulation method and radio wave propagation simulation program

Abstract

To provide a radio wave propagation simulation device capable of creating a 3D model.SOLUTION: A radio wave propagation simulation device 10 includes: an acquisition part 14 configured to acquire outdoor point group data; a filter processing part 16 configured to filter-process the acquired outdoor point group data; a ground surface separation processing part 18 configured to separate the filter-processed outdoor point group data into ground surface point group data and outdoor object point group data; a building separation processing part 20 configured to separate the outdoor object data into plant point group data and building point group data; a ground surface 3D model processing part 22 configured to create a 3D model of a ground surface according to the ground surface point group data; and a building 3D model processing part 24 configured to create a 3D model of a building according to the building point group data.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a radio wave propagation simulation apparatus, a radio wave propagation simulation method, and a radio wave propagation simulation program for creating a 3D model based on outdoor point cloud data.

Background Art

[0002] In recent years, there has been a demand for means for generating 3D models of the exterior of buildings and the internal structures of buildings (see Patent Document 1). Patent Document 1 discloses a technique for generating a 3D model of the internal structure of a building based on 3D point clouds representing the interior of the building.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the Society 5.0 era, large-scale communication using many communication devices is considered, and the realization of a CPS (Cyber Physical System) wireless emulator that can design, evaluate, and verify a radio wave system at low cost and in a short time is required. In a CPS wireless emulator, a radio wave propagation model based on the ray tracing method is studied, and a high-precision 3D model for both indoor and outdoor areas is required. However, Patent Document 1 is for creating a 3D model indoors. In the case of outdoors, the point cloud data covers a wide range, and the processing time becomes longer compared to creating an indoor 3D model, which is an issue.

[0005] The present invention has been made in consideration of the above problems, and an object thereof is to provide a radio wave propagation simulation apparatus, a radio wave propagation simulation method, and a radio wave propagation simulation program that can be used in the ray tracing method and can reduce the processing time for simulation using a 3D model.

Means for Solving the Problems

[0006] The radio wave propagation simulation apparatus according to the present invention includes an acquisition unit that acquires outdoor point cloud data, a filter processing unit that performs filter processing on the acquired outdoor point cloud data, a ground separation processing unit that separates the filtered outdoor point cloud data into ground point cloud data and outdoor object point cloud data, a building separation processing unit that separates the outdoor object data into plant point cloud data and building point cloud data, a ground 3D model processing unit that creates a 3D model of the ground based on the ground point cloud data, and a building 3D model processing unit that creates a 3D model of a building based on the building point cloud data. The building 3D model processing unit extracts contour data for each building in the horizontal direction with respect to the ground from the building point cloud data, processes each contour data based on a threshold value for the uneven portions of the contour formed by each contour data, and creates a 3D model of the building based on the processed each contour data.

[0007] In the radio wave propagation simulation apparatus, the building 3D model processing unit deletes the contour data related to the uneven portions below the threshold value from the contour data, and creates the 3D model of the building and the 3D model of the building based on the contour data in which the difference in cross-sectional area between adjacent contour data is equal to or less than a threshold value for the difference in cross-sectional area.

[0008] In the radio wave propagation simulation apparatus, the threshold value for the uneven portion is an integer multiple of the wavelength of the radio wave, and the threshold value for the difference in cross-sectional area is an integer multiple of the square of the wavelength of the radio wave.

[0009] The radio wave propagation simulation method according to the present invention includes an acquisition step of acquiring outdoor point cloud data, a filter processing step of filtering the acquired outdoor point cloud data, a ground separation processing step of separating the filtered outdoor point cloud data into ground point cloud data and outdoor object point cloud data, a building separation processing step of separating the outdoor object data into plant point cloud data and building point cloud data, a ground 3D model processing step of creating a 3D model of the ground based on the ground point cloud data, and a building 3D model processing step of creating a 3D model of a building based on the building point cloud data. The building 3D model processing step extracts contour data for each building in the horizontal direction with respect to the ground from the building point cloud data, processes each contour data based on a threshold for the uneven portions of the contour formed by each contour data, and creates a 3D model of the building based on the processed each contour data.

[0010] In the radio wave propagation simulation method, the building 3D model processing step deletes the contour data related to the uneven portions below the threshold from the contour data, and creates the 3D model of the building and the 3D model of the building based on the contour data where the difference in cross-sectional area between adjacent contour data is below the threshold for the difference in cross-sectional area.

[0011] In the radio wave propagation simulation method, the threshold for the uneven portions is an integer multiple of the wavelength of the radio wave, and the threshold for the difference in cross-sectional area is an integer multiple of the square of the wavelength of the radio wave.

[0012] The radio wave propagation simulation program according to the present invention includes an acquisition step of acquiring outdoor point cloud data, a filter processing step of filtering the acquired outdoor point cloud data, a ground separation processing step of separating the filtered outdoor point cloud data into ground point cloud data and outdoor object point cloud data, a building separation processing step of separating the outdoor object data into plant point cloud data and building point cloud data, a ground 3D model processing step of creating a 3D model of the ground based on the ground point cloud data, and a building 3D model processing step of creating a 3D model of a building based on the building point cloud data, and is a radio wave propagation simulation program for causing a computer to execute. In the building 3D model processing step, contour data for each building in the horizontal direction with respect to the ground is extracted from the building point cloud data, and each contour data is processed based on a threshold value for the uneven portions of the contour formed by each contour data, and a 3D model of the building is created based on the processed contour data.

[0013] In the radio wave propagation simulation program, the building 3D model processing step deletes the contour data related to the uneven portions below the threshold value from the contour data, and creates the 3D model of the building based on the contour data where the difference in the cross-sectional area of adjacent contour data is below the threshold value for the difference in cross-sectional area.

[0014] In the radio wave propagation simulation program, the threshold value for the uneven portions is an integer multiple of the wavelength of the radio wave, and the threshold value for the difference in cross-sectional area is an integer multiple of the square of the wavelength of the radio wave.

Effect of the Invention

[0015] The radio wave propagation simulation device, radio wave propagation simulation method, and radio wave propagation simulation program of the present invention can be used in the ray tracing method and can reduce the processing time for simulation using a 3D model.

Brief Description of the Drawings

[0016]

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Embodiments for Carrying Out the Invention

[0017] Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an explanatory diagram of a radio wave propagation simulation apparatus 10 according to an embodiment of the present invention.

[0018] <Explanation of the configuration of the radio wave propagation simulation apparatus 10> The radio wave propagation simulation device 10 includes a control unit 12, an acquisition unit 14, a filter processing unit 16, a ground separation processing unit 18, a building separation processing unit 20, a ground 3D model processing unit 22, a building 3D model processing unit 24, and a storage unit 26, which are interconnected via a bus 28. The control unit 12 includes a CPU, a ROM, and a RAM, and is a control unit that performs overall control of the control unit 12.

[0019] The acquisition unit 14 is a means for acquiring outdoor point cloud data. Here, the outdoor point cloud data includes point cloud data measured by an aircraft laser and point cloud data measured by an in-vehicle radar using an MMS (Mobile Mapping System), etc. The aircraft laser is excellent at acquiring point cloud data of the upper part of a structure, and the MMS is excellent at acquiring point cloud data of structures near the ground surface.

[0020] The filter processing unit 16 is a means for performing filter processing on the outdoor point cloud data. The filter processing is a process of thinning out points and reducing the density of the point cloud in order to speed up the processing of the point cloud data. As the filter processing, for example, a Voxel Grid Filter can be used. Here, the Voxel Grid Filter is a means for arranging 3D cubic grids in the point cloud, regarding the center of gravity of the point cloud existing in each grid as an approximation point of each point, and replacing the original point cloud data with that single center of gravity point.

[0021] The ground separation processing unit 18 is a means for separating the filtered outdoor point cloud data into ground point cloud data and outdoor object point cloud data. Here, the ground point cloud data is point cloud data representing the ground. Also, the outdoor object point cloud data is point cloud data obtained by removing the ground point cloud data from the outdoor point cloud data.

[0022] The building separation processing unit 20 is a means for separating the separated outdoor object data into plant point cloud data and building point cloud data. Here, the plant point cloud data is point cloud data representing plants, and the building point cloud data is point cloud data representing buildings.

[0023] The ground 3D model processing unit 22 is a means for creating a 3D model of the ground based on the ground point cloud data. The building 3D model processing unit 24 is a means for creating a 3D model of the building based on the building point cloud data. Predetermined data is stored in the storage unit 26.

[0024] <Description of the operation of the radio wave propagation simulation device 10> Next, the operation of the radio wave propagation simulation device 10 will be described with reference to FIG. 2. FIG. 2 is an explanatory diagram of the processing procedure of the radio wave propagation simulation device 10 according to the embodiment of the present invention.

[0025] First, in the radio wave propagation simulation device 10, the acquisition unit 14 acquires outdoor point cloud data (step S1). The filter processing unit 16 performs filter processing on the acquired outdoor point cloud data (step S2).

[0026] Next, based on FIG. 3, the separation of the ground point cloud data will be described. FIG. 3 is an explanatory diagram of the lowest point map. The lowest point map is divided into a grid pattern at a predetermined interval on the xy plane in the space of the outdoor object point cloud data, and the height of the lowest point in each divided grid is entered in each grid. For example, in FIG. 3, the lowest points along the y-axis are 1, 5, 5, 1, 1, 1.

[0027] The ground separation processing unit 18 separates the filtered outdoor point cloud data into ground point cloud data and outdoor object point cloud data (step S3). Specifically, the ground separation processing unit 18 divides the space into a grid pattern of, for example, 1 m on the xy plane, extracts the lowest point in each divided grid, and enters the height for each grid pattern to create a lowest point map. In the created lowest point map, the ground separation processing unit 18 clusters the locations where the lowest height is continuous, and sets the largest clustered area as the ground area. In FIG. 3, since the lowest height is "1", the area where the lowest height of "1" is continuously connected from the grid of "1" is the clustered area and becomes the ground area. The remaining area becomes the outdoor object point cloud data.

[0028] The building separation processing unit 20 separates the outdoor object data into plant point cloud data and building point cloud data (step S4). Specifically, the building separation processing unit 20 clusters the point clouds related to the outdoor object data where the distance between the point clouds on the xy plane is within a predetermined distance, for example, within 50 cm. The building separation processing unit 20 separates the plant point cloud data and the building point cloud data based on the curvature σ in order to evaluate the smoothness of the object represented by the set of coordinate information for the clustered point clouds. When 0 < σ < 0.07, the building separation processing unit 20 determines it as building point cloud data, and when 0.07 ≤ σ < 0.33, it determines it as plant point cloud data.

[0029] σ = λ0 / (λ0 + λ1 + λ2) (1) λ0, λ1, λ2: Eigenvalues of the covariance matrix C

[0030]

Number

[0031] Next, based on FIGS. 4A, 4B, 5A, and 5B, the creation of the 3D model of the ground will be described. FIG. 4A is an explanatory diagram of the ground height map, FIG. 4B is an explanatory diagram of the 3D model, FIG. 5A is an explanatory diagram of the ground point cloud data, and FIG. 5B is an explanatory diagram of the 3D model of the ground.

[0032] The ground 3D model processing unit 22 creates a 3D model of the ground based on the ground point cloud data separated by the ground separation processing unit 18 (step S5). Specifically, the ground 3D model processing unit 22 extracts the median value within each divided grid of the ground point cloud data and fills in its height for each grid to create a ground height map (see Fig. 4A). Based on the ground height map, the ground 3D model processing unit 22 creates a triangular mesh type 3D model by combining triangular meshes (see Fig. 4B). When the ground 3D model processing unit 22 creates a 3D model based on the ground point cloud data shown in Fig. 5A, it can create a triangular mesh type 3D model shown in Fig. 5B. Note that areas where the ground is missing due to buildings or the like may be interpolated with neighboring data.

[0033] Next, based on Figs. 6A to 6C, the creation of a 3D model of a building will be described. Fig. 6A is an explanatory diagram of building point cloud data, Fig. 6B is an explanatory diagram of contour data, and Fig. 6C is an explanatory diagram of a 3D building model.

[0034] The building 3D model processing unit 24 creates a 3D model 36 of the building based on the building point cloud data separated by the building separation processing unit 20 (step S6). Specifically, the building 3D model processing unit 24 extracts the maximum value within each divided grid of the building point cloud data (see Fig. 6A) and fills in its height for each grid to create a building height map. The building 3D model processing unit 24 extracts contour data 30A, 30B, 30C for each height of the building height map (see Fig. 6B). Based on the polygonal columns formed by stacking the extracted contour data 30, the building 3D model processing unit 24 creates 3D models 36A, 36B, 36C (see Fig. 6C).

[0035] In addition, the building 3D model processing unit 24 can simplify the 3D model in order to reduce the processing time for simulations using the 3D model. Regarding this simplification, the creation of the 3D model of the building will be described based on FIGS. 7A, 7B, 8A, 8B, 9A, and 9B. FIG. 7A is an explanatory diagram of the horizontal processing of the contour data before processing, and FIG. 7B is an explanatory diagram of the horizontal processing of the contour data after processing. FIG. 8A is an explanatory diagram of the contour data before the vertical processing of the contour data, FIG. 8B is an explanatory diagram of the 3D model after the vertical processing of the contour data, FIG. 9A is an explanatory diagram of the outdoor point cloud data, and FIG. 9B is an explanatory diagram of the 3D model corresponding to the outdoor point cloud data.

[0036] First, the horizontal processing of the contour data 30 by the building 3D model processing unit 24 will be described. The building 3D model processing unit 24 extracts the contour data 30 for each building in the horizontal direction with respect to the ground from the building point cloud data. The building 3D model processing unit 24 performs a process of deleting the uneven portions 32 on the outer edge of the contour piece formed by each of the extracted contour data 30, that is, the uneven portions 32 of the contour. As a processing method, the Douglas-Peucker method is applied and processed using the uneven portions 32.

[0037] Specifically, the building 3D model processing unit 24 compares the distance L from the top 34 of the uneven portion 32 of the contour with the allowable distance ε which is a threshold value, and performs processing based on the comparison result. As a comparison result, for the uneven portion 32 where L < ε, the building 3D model processing unit 24 deletes the contour data related to the uneven portion 32, and for the uneven portion 32 where L ≧ ε, the building 3D model processing unit 24 maintains the contour data related to the uneven portion 32. In the contour data before processing shown in FIG. 7A, as the uneven portions 32, there are four locations, uneven portion 32A, uneven portion 32B, uneven portion 32C, and uneven portion 32D. The distances L from the top 34 of each of the uneven portions 32A, 32B, and 32C are less than the allowable distance ε, and the distance L of the uneven portion 32D is ε or more. When the building 3D model processing unit 24 processes the contour data 30, as shown in FIG. 7B, the uneven portions 32A, 32B, and 32C are deleted, and only the uneven portion 32D is maintained.

[0038] Next, the vertical processing of the contour data 30 by the building 3D model processing unit 24 will be described. The building 3D model processing unit 24 acquires the cross-sectional area S of adjacent contour data 30, compares the difference in the cross-sectional area S with a threshold value (δ) for the difference in the cross-sectional area, and performs processing based on the comparison result. As a comparison result, when the difference in the cross-sectional area is less than δ, the building 3D model processing unit 24 combines the adjacent contour data 30, and a 3D model is formed. When the difference in the cross-sectional area is greater than or equal to δ, the building 3D model processing unit 24 will not combine the adjacent contour data 30.

[0039] Specifically, the building 3D model processing unit 24 acquires the cross-sectional areas S of the contour data 30A, 30B, and 30C. Assume that the cross-sectional areas S of the contour data 30A, 30B, and 30C are SA, SB, and SC, respectively. Next, the building 3D model processing unit 24 compares the difference in the cross-sectional area S of the adjacent contour data 30 with the threshold value δ. The building 3D model processing unit 24 compares the difference in the cross-sectional areas (SB - SA) between the contour data 30A and 30B with the threshold value δ. Since SB - SA < δ, the building 3D model processing unit 24 combines the contour data 30A and the contour data 30B to create a 3D model 36D. Next, the building 3D model processing unit 24 compares the difference in the cross-sectional areas (SC - SB) between the contour data 30B and 30C with the threshold value δ. Since SC - SB > δ, the contour data 30B and the contour data 30C will not be combined. In the pre-processing contour data in the vertical direction of the contour data shown in FIG. 8A, there are three pieces of contour data 30, namely, the contour data 30A, 30B, and 30C. When the building 3D model processing unit 24 processes the contour data 30, as shown in FIG. 8B, the contour data 30A and the contour data 30B are combined to form a 3D model 36D, and the contour data 30C is created as a 3D model 36C. The contour data 30 to be processed is reduced.

[0040] Here, as a verification example, the allowable distance ε is set to ε = nλ. Here, n is an integer and λ is the wavelength of the radio wave propagation simulation of the radio wave propagation simulation device 10. For example, in the simulation of Wi-SUN (Wireless Smart Utility Network), the frequency is 922 MHz and λ = 0.33 m. As the allowable distance ε which is the threshold value, an allowable distance ε = 3 m (n = 10) is preferable. Also, in the case of this verification example, the upper limit value of ε is 30λ (n = 30). As other main frequency bands, in the unmanned mobile body image transfer system, the frequency is 169 MHz, 2.4 GHz, 5.7 GHz, in the dedicated short-range communication DSRC (Dedicated Short-Range Communications), the frequency is 5.8 GHz, in the in-vehicle radar, the frequency is 70 GHz, in the wireless LAN, 2.4 GHz, 5 GHz, in 5G, 28 GHz, 3.7 GHz, 5 GHz, and in the local 5G, 28 GHz. It is preferable to set the allowable distance ε according to the wavelength.

[0041] Also, the threshold value δ of the difference in cross-sectional area is δ = 10ε 2 is set. Thereby, a 3D model suitable for radio wave propagation simulation at an arbitrary wavelength can be created.

[0042] Based on the outdoor point cloud data shown in FIG. 9A, creating a 3D model is shown in FIG. 8B.

[0043] As described above, the radio wave propagation simulation apparatus 10 includes an acquisition unit 14 that acquires outdoor point cloud data, a filter processing unit 16 that performs filter processing on the acquired outdoor point cloud data, a ground separation processing unit 18 that separates the filtered outdoor point cloud data into ground point cloud data and outdoor object point cloud data, a building separation processing unit 20 that separates the outdoor object data into plant point cloud data and building point cloud data, a ground 3D model processing unit 22 that creates a 3D model of the ground based on the ground point cloud data, and a building 3D model processing unit 24 that creates a 3D model of a building based on the building point cloud data. The building 3D model processing unit 24 extracts contour data 30 for each building in the horizontal direction with respect to the ground from the building point cloud data, processes each contour data 30 based on a threshold value for the uneven portions 32 of the contour formed by each contour data 30, and creates a 3D model of the building based on the processed each contour data 30.

[0044] In the radio wave propagation simulation apparatus 10, it is available for the ray tracing method and can reduce the processing time for simulation using a 3D model.

[0045] Also, in the radio wave propagation simulation apparatus 10, the building 3D model processing unit 24 deletes the contour data 30 related to the uneven portions 32 below the threshold value from the contour data 30, and creates the 3D model of the building and the 3D model of the building based on the contour data 30 where the difference in the cross-sectional area of the adjacent contour data 30 is below the threshold value for the difference in the cross-sectional area.

[0046] Also, in the radio wave propagation simulation apparatus 10, the threshold value for the uneven portion is an integer multiple of the wavelength of the radio wave, and the threshold value for the difference in the cross-sectional area is an integer multiple of the square of the wavelength of the radio wave.

[0047] <Description of Embodiment Related to Program> The above-described radio wave propagation simulation apparatus 10 is realized, for example, by a computer 100 configured as shown in FIG. 10. FIG. 10 is a hardware explanatory diagram showing an example of a computer 100 that realizes the functions of the radio wave propagation simulation apparatus 10. The computer 100 includes a CPU 110, a RAM 120, a ROM 130, an auxiliary storage unit 140, a network interface (NW I / F) 150, an input unit 160, an output unit 170, and a storage medium interface (storage medium I / F) 180. These units are connected by a bus 190.

[0048] The CPU 110 operates based on programs stored in the ROM 130 or the auxiliary storage unit 140 and controls each unit. In the ROM 130, there are stored boot programs such as BIOS (Basic Input Output System) executed by the CPU 110 when the computer 100 is started up, and programs dependent on the hardware of the computer 100.

[0049] The auxiliary storage unit 140 is a large-capacity storage unit. In the auxiliary storage unit 140, programs executed by the CPU 110 and data used by the programs are stored.

[0050] The network interface 150 is a network interface for connecting to a public line.

[0051] The input unit 160 is an input device such as a keyboard and a mouse. The input device may include a touch panel, a camera, a microphone, etc.

[0052] The output unit 170 is a display unit such as a display. Also, the output unit 170 may include a speaker.

[0053] The memory medium interface 180 reads a program or data stored in a recording medium and provides it to the CPU 110 via the RAM 120. Examples of the recording medium include optical recording media such as DVDs, DVD-RAMs, Blu-ray (registered trademark) Disks, semiconductor memories such as flash memories, magneto-optical recording media such as MOs, tape media, magnetic recording media, and the like.

[0054] When the computer 100 functions as the radio wave propagation simulation device 10, the CPU 110 reads a program from the auxiliary storage unit 140 and executes the program loaded on the RAM 120 to realize the function of the contour data 30. Further, the CPU 110 may realize the function of the radio wave propagation simulation device 10 by reading a program from a recording medium via the memory medium interface 180 and executing the program loaded on the RAM 120.

[0055] The radio wave propagation simulation program includes an acquisition step of acquiring outdoor point cloud data, a filter processing step of filtering the acquired outdoor point cloud data, a ground separation processing step of separating the filtered outdoor point cloud data into ground point cloud data and outdoor object point cloud data, a building separation processing step of separating the outdoor object data into plant point cloud data and building point cloud data, a ground 3D model processing step of creating a 3D model of the ground based on the ground point cloud data, and a building 3D model processing step of creating a 3D model of a building based on the building point cloud data. The radio wave propagation simulation program is for causing the computer 100 to execute. In the building 3D model processing step, contour data 30 for each building in the horizontal direction with respect to the ground is extracted from the building point cloud data, and each contour data 30 is processed based on a threshold value for the uneven portions 32 of the contour formed by each contour data 30, and a 3D model of the building is created based on the processed contour data 30.

[0056] Note that the present invention is not limited to the above-described embodiments, and it goes without saying that various configurations can be adopted without departing from the gist of the present invention.

Explanation of Reference Numerals

[0057] 10…Radio wave propagation simulation device 12…Control unit 14…Acquisition unit 16…Filter processing unit 18…Ground separation processing unit 20…Building separation processing unit 22…Ground 3D model processing unit 24…Building 3D model processing unit 26…Memory unit 28, 190…Bus 30, 30A~30C, …Contour data 32, 32A~32D…Concave-convex part 34…Top part 36, 36A~36D…3D model 100…Computer 110…CPU 120…RAM 130…ROM 140…Auxiliary storage unit 150…Network interface 160…Input unit 170…Output unit 180…Memory medium interface

Claims

1. An acquisition unit that acquires outdoor point cloud data, A filter processing unit that performs filter processing on the acquired outdoor point cloud data, A ground separation processing unit that separates the filtered outdoor point cloud data into ground point cloud data and outdoor object point cloud data, A building separation processing unit that separates the outdoor object data into plant point cloud data and building point cloud data, A ground 3D model processing unit that creates a 3D model of the ground based on the ground point cloud data, A building 3D model processing unit that creates a 3D model of a building based on the building point cloud data, Comprising, The building 3D model processing unit, Extracts contour data for each building in the horizontal direction with respect to the ground from the building point cloud data, processes each contour data based on a threshold value for the concave and convex portions of the contour formed by each contour data, and creates a 3D model of the building based on the processed contour data. A radio wave propagation simulation device.

2. In the radio wave propagation simulation device according to Claim 1, The building 3D model processing unit, Deletes the contour data related to the concave and convex portions below the threshold value from the contour data, Based on the contour data where the difference in the cross-sectional area of adjacent contour data is less than or equal to the threshold value for the difference in cross-sectional area, creates the 3D model of the building and the 3D model of the building. A radio wave propagation simulation device.

3. In the radio wave propagation simulation device according to Claim 1 or 2, The threshold value for the concave and convex portions is an integer multiple of the wavelength of the radio wave, and the threshold value for the difference in cross-sectional area is an integer multiple of the square of the wavelength of the radio wave. A radio wave propagation simulation device.

4. An acquisition step of acquiring outdoor point cloud data, A filter processing step of performing filter processing on the acquired outdoor point cloud data, A ground separation processing step of separating the filtered outdoor point cloud data into ground point cloud data and outdoor object point cloud data, A building separation processing step of separating the outdoor object data into plant point cloud data and building point cloud data, A ground 3D model processing step of creating a 3D model of the ground based on the ground point cloud data, A building 3D model processing step of creating a 3D model of a building based on the building point cloud data, Comprising, The building 3D model processing step, A radio wave propagation simulation method for extracting contour data for each building in the horizontal direction with respect to the ground from the building point cloud data, processing each contour data based on a threshold value for the concave and convex portions of the contour formed by each contour data, and creating a 3D model of the building based on the processed contour data for each building.

5. In the radio wave propagation simulation method according to claim 4, The building 3D model processing step is as follows: Deleting the contour data related to the concave and convex portions below the threshold value from the contour data, Based on the contour data where the difference in the cross-sectional area of adjacent contour data is equal to or less than a threshold value for the difference in cross-sectional area, a radio wave propagation simulation method for creating the 3D model of the building and the 3D model of the building.

6. In the radio wave propagation simulation method according to claim 4 or 5, The threshold value for the concave and convex portions is an integer multiple of the wavelength of the radio wave, and the threshold value for the difference in cross-sectional area is an integer multiple of the square of the wavelength of the radio wave in the radio wave propagation simulation method.

7. An acquisition step of acquiring outdoor point cloud data, A filter processing step of filtering the acquired outdoor point cloud data, A ground separation processing step of separating the filtered outdoor point cloud data into ground point cloud data and outdoor object point cloud data, A building separation processing step of separating the outdoor object data into plant point cloud data and building point cloud data, A ground 3D model processing step of creating a 3D model of the ground based on the ground point cloud data, A building 3D model processing step of creating a 3D model of the building based on the building point cloud data, A radio wave propagation simulation program for causing a computer to execute, comprising: The building 3D model processing step is as follows: Extracting contour data for each building in the horizontal direction with respect to the ground from the building point cloud data, processing each contour data based on a threshold value for the concave and convex portions of the contour formed by each contour data, and creating a 3D model of the building based on the processed contour data for each building.

8. In the radio wave propagation simulation program according to claim 7, The building 3D model processing step is as follows: Deleting the contour data related to the concave and convex portions below the threshold value from the contour data, A radio wave propagation simulation program that creates the 3D model of the building and the 3D model of the building based on the contour data whose difference in cross-sectional area of the adjacent contour data is equal to or less than the threshold value for the difference in cross-sectional area. **Claim 9** In the radio wave propagation simulation program according to claim 7 or 8, A radio wave propagation simulation program in which the threshold value for the uneven portion is an integer multiple of the wavelength of the radio wave, and the threshold value for the difference in area is an integer multiple of the square of the wavelength of the radio wave.

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