Interference evaluation method, interference evaluation device, and obstacle installation system

Abstract

When a radio station device is installed according to station installation position data indicating a position that is designated by a user and at which the radio station device is to be installed, an obstacle is set on a propagation path of radio waves emitted by the radio station device, and obstacle data indicating the positions of both ends of the set obstacle and the height thereof is generated. When the radio station device is installed according to the station installation position data and the obstacle is installed according to the obstacle data, an interference evaluation is performed in which the influence of interference caused by the radio waves emitted by the radio station device is evaluated at each of a plurality of evaluation points.

Description

Technical Field

[0001] The present invention relates to an interference evaluation method, an interference evaluation apparatus, and an obstacle installation system.

Background Art

[0002] Interference evaluation is used when making adjustments such as providing an appropriate distance between mutual usage locations or changing the communication direction so that interference does not occur in multiple wireless communications using the same frequency. For example, in the technology disclosed in Non-Patent Document 1, as a result of interference evaluation, as shown in FIG. 3 of Non-Patent Document 1, an interference tolerance area that can coexist with other wireless communication systems hatched in blue and an interference area that requires a review of the operation / installation conditions of other wireless communication systems hatched in red are distinguishable and shown.

[0003] In the technology disclosed in Patent Document 1, as a result of interference evaluation, as shown in FIG. 21 of Patent Document 1, the interfered stations on the map are indicated by a triangle mark "△", and the distance of the ridge considering the terrain and the like around it is indicated by a dashed line, the separation distance with a ridge is indicated by a dotted line, and the separation distance that becomes the worst value without considering the ridge is indicated by a solid line enclosure.

[0004] In the technology disclosed in Patent Document 2, as a result of interference evaluation, the result shown in FIG. 29 of Patent Document 2 can be shown. In FIG. 29 of Patent Document 2, the positions of three interfered stations A, B, and C are indicated by white circle marks "〇", the position of one interfering station is indicated by a black circle mark "●", and the antenna direction of the interfering station is indicated by a dashed arrow. Also, the periphery of the interfering station is divided into a mesh shape, and in each divided mesh, the difference in the power level of the radio wave reaching from the interfering station is shown by a plurality of types of hatching patterns.

[0005] By using the interference evaluation results as described above, it is possible to clearly determine how to make adjustments, for example, where to relocate a wireless station of one wireless communication system, in order to share and use with other wireless communication systems.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Non-Patent Documents

[0007]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0008] By the way, in the future, as the number of scenarios using wireless communication increases, it is expected that there will be an increasing number of cases where multiple wireless station devices for base stations must be installed and shared even at close distances where the influence of interference reaches. In this case, based only on the results of interference evaluation as disclosed in Patent Documents 1 and 2 and Non-Patent Document 1 above, it becomes difficult to clearly determine how to perform shared use between different wireless communication systems. Therefore, for example, it is expected that it will also be required to provide obstacles that shield radio waves between different wireless communication systems and perform interference evaluation while appropriately changing the position, length, and height of the obstacles to identify the appropriate position, length, and height of the obstacles that enable shared use between different wireless communication systems.

[0009] In view of the above circumstances, an object of the present invention is to provide a technology that enables interference evaluation after providing an obstacle whose position, length, and height can be arbitrarily changed in an environment where wireless communication is used.

Means for Solving the Problems

[0010] One aspect of the present invention is an interference evaluation method including: an obstacle setting step of setting an obstacle on the propagation path of the radio wave transmitted by the radio base station device when the radio base station device is installed according to the station installation position data indicating the position where the radio base station device is installed and designated by the user, and generating obstacle data indicating the positions and heights of both ends of the set obstacle; and an interference evaluation step of performing interference evaluation for each evaluation point of the influence of interference by the radio wave transmitted by the radio base station device when the radio base station device is installed according to the station installation position data and the obstacle is installed according to the obstacle data.

[0011] One aspect of the present invention is an interference evaluation apparatus including: an obstacle setting unit that sets an obstacle on the propagation path of the radio wave transmitted by the radio base station device when the radio base station device is installed according to the station installation position data indicating the position where the radio base station device is installed and designated by the user, and generates obstacle data indicating the positions and heights of both ends of the set obstacle; and an interference evaluation unit that performs interference evaluation for each evaluation point of the influence of interference by the radio wave transmitted by the radio base station device when the radio base station device is installed according to the station installation position data and the obstacle is installed according to the obstacle data.

[0012] One aspect of the present invention is an obstacle installation system including the above interference evaluation apparatus and an obstacle installation device that installs a physical object of the obstacle according to the obstacle data generated by the obstacle setting unit of the interference evaluation apparatus.

Advantages of the Invention

[0013] According to the present invention, it becomes possible to perform interference evaluation after providing an obstacle whose position, length, and height can be arbitrarily changed.

Brief Description of the Drawings

[0014]

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Modes for Carrying Out the Invention

[0015] (First Embodiment) Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of an interference evaluation apparatus 1 according to the first embodiment. The interference evaluation apparatus 1 includes a display unit 11, an operation unit 12, a map data storage unit 13, a terrain data storage unit 14, and an information processing unit 15. The display unit 11 includes, for example, a screen such as a liquid crystal display, and displays images, characters, numerical values, etc. on the screen. The operation unit 12 includes, for example, an input device such as a keyboard or a mouse. When the input device is operated by the user of the interference evaluation apparatus 1, the operation unit 12 moves the position of the mouse pointer displayed on the screen of the display unit 11, presses the image of a button included in the image displayed on the screen, obtains the position of the mouse pointer within the screen, and captures input data given by the user's operations on the keyboard or mouse, and performs processing related to various operations such as these.

[0016] The map data storage unit 13 stores in advance map data created according to a predetermined map coordinate system. Here, the predetermined map coordinate system is a so-called geographic coordinate system that indicates positions on the earth by latitude and longitude. However, the map coordinate system is not limited to the geographic coordinate system, and any coordinate system that indicates positions on the earth may be used. The terrain data storage unit 14 stores in advance terrain data that can generate a change in elevation, that is, a vertical cross-sectional view of the terrain, on a straight line connecting two different points when the latitudes and longitudes of the two different points are specified. Such map data and terrain data are provided, for example, by the Geospatial Information Authority of Japan.

[0017] The information processing unit 15 includes an execution condition setting unit 21, a base station installation position setting unit 22, an antenna pattern setting unit 23, an obstacle setting unit 24, an interference evaluation unit 25, and a memory unit 26. The execution condition setting unit 21 is activated by receiving an instruction signal from the operation unit 12 when the user performs an operation to activate the execution condition setting unit 21 on the operation unit 12. When activated, the execution condition setting unit 21 displays the execution condition setting screen 41 shown in FIG. 2 on the screen of the display unit 11. When the data for interference evaluation is given on the execution condition setting screen 41, the execution condition setting unit 21 takes in the given data for interference evaluation and writes the taken-in data for interference evaluation into the memory unit 26.

[0018] When an image of a map represented by map data is displayed on the screen of the display unit 11, the base station installation position setting unit 22 sets, as the position where the radio base station device is to be installed, the position of a point specified on the map by the user operating the operation unit 12. The base station installation position setting unit 22 detects the coordinates in the coordinate system of the screen of the set position via the operation unit 12, and converts the detected coordinates into the coordinates in the map coordinate system, that is, the latitude and longitude, based on the map data corresponding to the portion of the map displayed on the screen. The base station installation position setting unit 22 generates data including the latitude and longitude obtained by the conversion as base station installation position data indicating the position where the radio base station device is to be installed.

[0019] The antenna pattern setting unit 23 generates antenna pattern data, which is data given by the user operating the operation unit 12 and indicates the antenna pattern of the radio base station device installed at the position indicated by the base station installation position data.

[0020] When an image of a map represented by map data is displayed on the screen of the display unit 11, the obstacle setting unit 24 sets the positions of the start point and the end point of a line segment specified on the map by the user operating the operation unit 12 as the positions of both ends of the obstacle. The obstacle setting unit 24 detects the coordinates in the coordinate system of the screen of the positions of the start point and the end point via the operation unit 12, and converts the detected coordinates of the start point and the end point into the coordinates in the map coordinate system, that is, the latitude and the longitude, based on the map data corresponding to the portion of the map displayed on the screen.

[0021] For example, the obstacle setting unit 24 calculates the latitude and the longitude of the position of the midpoint between the start point and the end point from the latitude and the longitude of each of the start point and the end point obtained by the conversion. The obstacle setting unit 24 displays, on the screen of the display unit 11, the shape of the vertical cross section of the terrain between the installation position of the radio base station device and the midpoint of the obstacle based on the calculated latitude and longitude of the midpoint, the latitude and longitude positions indicated by the base station installation position data, and the terrain data stored in the terrain data storage unit 14. The obstacle setting unit 24 takes in a numerical value indicating the height of the obstacle specified by the user operating the operation unit 12 while referring to the shape of the vertical cross section of the terrain displayed on the screen, and generates data including the numerical value indicating the taken-in height and the latitude and longitude of each of the start point and the end point as obstacle data.

[0022] The interference evaluation unit 25 evaluates, for each evaluation point, the influence of interference by the radio wave transmitted by the radio base station device when the radio base station device is installed according to the base station installation position data and the obstacle is installed according to the obstacle data, based on the data written in the storage unit 26 as data for interference evaluation by the execution condition setting unit 21, that is, the data of the radio base station information including the base station installation position data and the antenna pattern data, the obstacle data, and the data given on the other execution condition setting screen 41. The storage unit 26 stores the data for interference evaluation written by the execution condition setting unit 21.

[0023] (Processing by the interference evaluation apparatus according to the first embodiment) FIG. 3 is a flowchart showing the processing flow by the interference evaluation apparatus 1. When the user of the interference evaluation apparatus 1 performs an operation to activate the execution condition setting unit 21 on the operation unit 12, the execution condition setting unit 21 in the information processing unit 15 is activated by receiving an instruction signal from the operation unit 12 due to the operation. When activated, the execution condition setting unit 21 displays the execution condition setting screen 41 of FIG. 2 on the screen of the display unit 11 (step Sa1).

[0024] When the user operates the operation unit 12 to move the mouse pointer to the new addition button 53 of "■ Wireless station information" on the execution condition setting screen 41 and presses the new addition button 53, for example, clicks the button of the mouse, the execution condition setting unit 21 receives an instruction signal from the operation unit 12 due to the operation and displays the wireless station information editing screen 42 shown in FIG. 5 on the screen of the display unit 11 (step Sa2). Thereafter, in the wireless station information editing screen 42, as the process of step Sa3, the subroutine process of the wireless station setting process shown in FIG. 4 is started.

[0025] (Setting the position of the wireless station device) Proceeding to FIG. 4, the user operates the operation unit 12 to move the mouse pointer to the position of the map display button 81 (in the wireless station information editing screen 42 shown in FIG. 5, this "map display button 81" is located at a position to the right of the latitude / longitude 83 which is the position of the wireless station). When the user performs an operation of pressing the map display button 81 corresponding to the position of the mouse pointer on the operation unit 12, the station installation position setting unit 22 is activated by receiving an instruction signal from the operation unit 12 due to the operation. When activated, the station installation position setting unit 22 reads map data from the map data storage unit 13. The station installation position setting unit 22 displays the wireless station setting screen 43 shown in FIG. 6 including the image of the map represented by the read map data on the screen of the display unit 11. However, at this point, the triangular mark "▲" indicated by the reference numeral 151 is not displayed on the wireless station setting screen 43 (step Sb1).

[0026] When displaying the map included in the wireless station setting screen 43, that is, the layer of the map, such as the display magnification and scale of the map, the layer predetermined in the information processing unit 15 is applied and is not included in the items set by the user. The map included in the wireless station setting screen 43 can be enlarged or reduced, for example, by operating the zoom tool indicated by the reference numeral 141 with a mouse. For example, when the mouse pointer exists on the map, by performing a drag operation of the mouse, that is, an operation of moving the mouse pointer while pressing the button of the mouse, the display range of the map can be shifted in an arbitrary direction. The processes of enlarging and reducing the map and shifting the display range are processes performed by the base station installation position setting unit 22 according to the instruction signal from the operation unit 12 that has received the operations of enlarging and reducing the map and shifting the display range. In addition, in the functional unit other than the base station installation position setting unit 22 that performs map display, regarding the application of the layer predetermined in the information processing unit 15 and the processes related to the map such as enlargement and reduction and shifting of the display range, unless otherwise described, it is assumed to have the same configuration as the base station installation position setting unit 22.

[0027] By the user operating the operation unit 12, after the map in the desired range is displayed on the wireless station setting screen 43, the mouse pointer is moved to a position on the map included in the wireless station setting screen 43, which is the position where the wireless station device is to be installed. When the user performs an operation of selecting the position indicated by the mouse pointer on the operation unit 12, for example, an operation of clicking the button of the mouse, the operation unit 12 detects the coordinates of the selected position in the coordinate system of the screen (step Sb2). The operation unit 12 outputs the data of the detected coordinates to the base station installation position setting unit 22. The base station installation position setting unit 22 takes in the data of the coordinates output by the operation unit 12, and based on the map data corresponding to the portion of the map displayed on the screen when the data is taken in, converts the taken-in coordinates from the coordinate system of the screen to the map coordinate system to obtain coordinates represented by latitude and longitude. The base station installation position setting unit 22 generates data including the coordinates represented by the latitude and longitude obtained by the conversion as base station installation position data indicating the position where the wireless station device is to be installed (step Sb3).

[0028] The station installation position setting unit 22 displays a station installation position mark 151, which is represented by, for example, a triangle mark "▲", at a position corresponding to the station installation position data on the map of the wireless station setting screen 43 in FIG. 6, that is, at the position where the wireless station device is to be installed. The station installation position setting unit 22 displays the latitude numerical value included in the station installation position data in the latitude text box at the portion indicated by reference numeral 83 on the wireless station information editing screen 42 in FIG. 5, and displays the longitude numerical value included in the station installation position data in the longitude text box at the portion indicated by reference numeral 83 (step Sb4). Incidentally, in a state where the wireless station setting screen 43 is displayed on the screen of the display unit 11, assume that the user operates the operation unit 12 to rewrite any one of the numerical values displayed in the latitude and longitude text boxes displayed at the portion indicated by reference numeral 83 on the wireless station information editing screen 42. In this case, the station installation position setting unit 22 takes in the rewritten numerical value, and changes the position of the station installation position mark 151 displayed on the wireless station information editing screen 42 according to the taken-in numerical value.

[0029] When the user operates the operation unit 12, the mouse pointer is moved to the position of the button indicated by reference numeral 43e on the wireless station setting screen 43. When the user performs an operation of pressing the button corresponding to the position of the mouse pointer on the operation unit 12, the station installation position setting unit 22 receives an instruction signal from the operation unit 12 due to the operation, and closes the wireless station setting screen 43, that is, deletes it from the screen of the display unit 11.

[0030] (Setting of the antenna pattern of the wireless station device) When the user operates the operation unit 12, the mouse pointer is moved to the position of the antenna pattern display button 82 on the wireless station information editing screen 42 in FIG. 5. When the user performs an operation of pressing the antenna pattern display button 82 on the operation unit 12, the antenna pattern setting unit 23 is activated upon receiving an instruction signal from the operation unit 12 for this operation. When activated, the antenna pattern setting unit 23 displays an antenna pattern setting screen 44 shown in FIG. 7 on the screen of the display unit 11. In the antenna pattern setting screen 44, the lower figure on the right shows the antenna pattern 161 in the horizontal plane, and the upper figure on the right shows the antenna pattern 162 in the vertical plane. The figure on the left shows a three-dimensional antenna pattern 163 obtained by combining the antenna pattern 161 in the horizontal plane and the antenna pattern 162 in the vertical plane.

[0031] The user operates the operation unit 12 to move the mouse pointer to any position on the curve indicating the antenna pattern 161 in the horizontal plane of the antenna pattern setting screen 44 and performs a mouse dragging operation. When the antenna pattern setting unit 23 receives the movement amount obtained by the dragging operation from the operation unit 12, it deforms the curve indicating the antenna pattern 161 in the horizontal plane according to the received movement amount. Similarly, the user operates the operation unit 12 to move the mouse pointer to any position on the curve indicating the antenna pattern 162 in the vertical plane of the antenna pattern setting screen 44 and performs a mouse dragging operation. When the antenna pattern setting unit 23 receives the movement amount obtained by the dragging operation from the operation unit 12, it deforms the curve indicating the antenna pattern 162 in the vertical plane according to the received movement amount.

[0032] The antenna pattern setting unit 23 reflects the deformation of the horizontal plane antenna pattern 161 and the vertical plane antenna pattern 162 in the three-dimensional antenna pattern 163. The antenna pattern setting unit 23 displays, in the text box of the antenna azimuth angle at the portion indicated by reference numeral 84-1 in the radio station information editing screen 42 of FIG. 5, a numerical value corresponding to the shape of the curve indicating the horizontal plane antenna pattern 161, for example, in the unit [deg]. The antenna pattern setting unit 23 displays, in the text box of the antenna elevation angle at the portion indicated by reference numeral 84-1 in the radio station information editing screen 42, a numerical value corresponding to the shape of the curve indicating the vertical plane antenna pattern 162, for example, in the unit [deg]. Note that the antenna azimuth angle is the angle by which the pointing direction indicated by the curve of the horizontal plane antenna pattern 161 is inclined with respect to the front direction of the antenna in the horizontal plane. The antenna elevation angle is the angle by which the pointing direction indicated by the curve of the vertical plane antenna pattern 162 is inclined with respect to the front direction of the antenna in the vertical plane. Here, the front direction of the antenna is the upward direction in the antenna pattern setting screen 44.

[0033] As a result, the user can set an antenna pattern having a desired directivity by deforming both or either one of the curve indicating the horizontal-plane antenna pattern 161 and the curve indicating the vertical-plane antenna pattern 162 while referring to the three-dimensional antenna pattern 163 on the antenna pattern setting screen 44. When the directivity of the antenna tilts from the front direction of the antenna, the degree of influence of interference by radio waves also changes. Therefore, by performing interference evaluation based on the directivity of the antenna, it becomes possible to obtain a result showing a more realistic influence of interference. In a state where the antenna pattern setting screen 44 is displayed on the screen of the display unit 11, assume that the user operates the operation unit 12 and rewrites any one of the numerical values displayed in the text boxes for the antenna azimuth angle and the antenna elevation angle of the portion indicated by reference numeral 84-1 in the radio station information editing screen 42 of FIG. 5. In this case, the antenna pattern setting unit 23 takes in the rewritten numerical value and updates the display of the curve indicating the horizontal-plane antenna pattern 161, the curve indicating the vertical-plane antenna pattern 162, and the three-dimensional antenna pattern 163 displayed on the antenna pattern setting screen 44 of FIG. 7 according to the taken-in numerical value.

[0034] When the setting of the antenna pattern is completed, the user operates the operation unit 12 to move the mouse pointer to the position of the button indicated by the symbol 44e on the antenna pattern setting screen 44. When the user presses the button corresponding to the position of the mouse pointer on the operation unit 12, upon receiving an instruction signal from the operation unit 12 for this operation, the antenna pattern setting unit 23 closes the antenna pattern setting screen 44, that is, erases it from the screen of the display unit 11 (step Sb5). Note that in FIG. 4 which explains the wireless station setting up to this point, the antenna pattern was set in step Sb5. The setting of that antenna pattern was carried out on the antenna pattern setting screen 44 shown in FIG. 7 starting from pressing the button of the antenna pattern display 82 in FIG. 5. By slightly changing the operation as described above, it is also possible to set the antenna pattern as information to be registered in the wireless system in advance. In this case, the antenna pattern to be registered in the information of the wireless system is set in advance on the antenna pattern setting screen 44 shown in FIG. 7. When the operator sets the system name of the system specifications on the wireless station information editing screen 42 in FIG. 5 as a condition for interference evaluation, the operator can select by associating an antenna name corresponding to that wireless system. The antenna pattern corresponding to this antenna name is read out on the antenna pattern display 82 and shows the antenna pattern in FIG. 7 described above. That is, in the operation flow of FIG. 4, instead of "setting of the antenna pattern (step Sb5)", it may be set to "selection of the antenna (antenna pattern together with the antenna name)".

[0035] (Other settings related to the wireless station device) On the radio station information editing screen 42 of FIG. 5, the user operates the operation unit 12 to perform a selection operation on buttons of items other than the latitude, longitude of the part indicated by reference numeral 83, the antenna azimuth angle, and the antenna elevation angle of the part indicated by reference numeral 84-1, and an operation of writing characters and numerical values in a text box or the like (step Sb6). Note that numerical values are already displayed in the text boxes for the latitude and longitude of the part indicated by reference numeral 83, the antenna azimuth angle, and the antenna elevation angle of the part indicated by reference numeral 84-1 due to the processing in steps Sb1 to Sb5 described above. However, at the timing of the processing in step Sb6, the user may directly rewrite and change these numerical values.

[0036] By operating the operation unit 12, the user moves the mouse pointer to the position of the OK button 86 on the radio station information editing screen 42. When the user performs an operation of pressing the OK button 86 corresponding to the position of the mouse pointer on the operation unit 12, the execution condition setting unit 21 receives an instruction signal from the operation unit 12 for this operation, captures the radio station information data, which is all the data given by the user's operation on the radio station information editing screen 42, stores the captured radio station information data in an internal storage area, and also reflects it on the execution condition setting screen 41. The execution condition setting unit 21 closes the radio station information editing screen 42, that is, deletes it from the screen of the display unit 11 (step Sb7).

[0037] For example, assume that the radio station information data generated by steps Sb1 to Sb6 described above is data generated when the button of "interfering station" is selected in a radio button for selecting either "interfering station" or "interfered station" in the part indicated by reference numeral 85 on the radio station information editing screen 42 of FIG. 5. Note that the interfering station means a radio station on the side that causes interference by transmitted radio waves and corresponds to the transmitting station. In contrast, the interfered station means a radio station on the side that receives interference by received radio waves and corresponds to the receiving station.

[0038] By the user operating the operation unit 12, the mouse pointer is moved to the position of the transmission station selection button 51 on the execution condition setting screen 41 in FIG. 2. When the user performs an operation of pressing the transmission station selection button 51 corresponding to the position of the mouse pointer on the operation unit 12, upon receiving an instruction signal from the operation unit 12 due to the operation, the execution condition setting unit 21 detects, from the data of the radio station information stored in the internal storage area, the data of the radio station information that contains data indicating that the "interfering station" button in the part indicated by the code 85 has been selected. The execution condition setting unit 21 displays, in the radio station information table 52 that shows data in tabular form on the execution condition setting screen 41, the record corresponding to the detected data of the radio station information. In the radio station information table 52, one record corresponding to one piece of radio station information data is displayed in one line. Therefore, when the execution condition setting unit 21 detects data of a plurality of radio station information, a plurality of lines of records corresponding to each of the data of the plurality of radio station information are displayed in the radio station information table 52.

[0039] Here, assume that the user wishes to modify or delete a record displayed in the wireless station information table 52 (step Sb8). When the user wishes to modify a record displayed in the wireless station information table 52 (step Sb8, modification), by operating the operation unit 12, the mouse pointer is moved to the position of any one of the records for which modification is desired and which is displayed in the wireless station information table 52 of the execution condition setting screen 41 in FIG. 2. After the user performs an operation of selecting the record corresponding to the position of the mouse pointer with respect to the operation unit 12, the mouse pointer is further moved to the modification button 54. When the user performs an operation of pressing the modification button 54 with respect to the operation unit 12, upon receiving an instruction signal from the operation unit 12 due to the operation, the execution condition setting unit 21 again displays the wireless station information editing screen 42 in FIG. 5 on the screen of the display unit 11 with the data included in the selected record being displayed. Thereafter, when the user modifies the station installation position data, the processes of steps Sb1 to Sb4 are performed. When the user modifies the antenna pattern, the process of step Sb5 is performed. When the user makes a selection state of a button, or modifies characters, numerical values, etc. displayed on the wireless station information editing screen 42, the process of step Sb6 is performed. After the modification is completed, the process of step Sb7 is performed.

[0040] In the case of the process of step Sb1 performed during the correction, the base station installation position setting unit 22 displays on the wireless station setting screen 43 of FIG. 6 a map within a range where the position of the base station installation position mark 151 corresponding to the selected record is at the center position of the map. In the case of the process of step Sb2 performed during the correction, since the base station installation position mark 151 is already displayed on the map, the following process will be performed. That is, the user moves the mouse pointer to the base station installation position mark 151, drags the base station installation position mark 151, and performs an operation to move the base station installation position mark 151 to a desired position. When the base station installation position mark 151 reaches the desired position by the drag operation and the user ends the drag operation, the operation unit 12 detects the position of the base station installation position mark 151 at the end of the drag operation as the position where the corrected wireless station device is to be installed. Thereafter, the processes of steps Sb3 and Sb4 are performed.

[0041] When the user first specifies the position of the wireless station device on the map and when the process of step Sb4 ends when correcting the position of the wireless station device on the map, if the user wishes to correct the position of the wireless station device set immediately before on the map, after step Sb4, the process from step Sb1 may be performed again. Also in this case, the processes of steps Sb1 and Sb2 performed during the above-described correction are performed, and thereafter, the processes of steps Sb3 and Sb4 are performed.

[0042] When the user desires to delete a record displayed in the wireless station information table 52 (step Sb8, deletion), by operating the operation unit 12, the mouse pointer is moved to the position of any one of the records in the wireless station information table 52 on the execution condition setting screen 41 of FIG. 2 for which deletion is desired. After the user performs an operation to select the record corresponding to the position of the mouse pointer on the operation unit 12, the mouse pointer is further moved to the delete button 55. When the user performs an operation of pressing the delete button 55 on the operation unit 12, upon receiving an instruction signal from the operation unit 12 due to the operation, the execution condition setting unit 21 deletes the selected record from the wireless station information table 52 and deletes the data corresponding to the selected record from the internal storage area (step Sb9).

[0043] When the user desires neither modification nor deletion, assuming that the creation of the wireless station information is completed (step Sb8, completion), the subroutine processing of the wireless station setting process ends. Note that in the subroutine processing of the wireless station setting process in FIG. 4, the order of performing the processing with steps Sb1 to Sb four as one set, the processing of step Sb5, and the processing of step Sb6 does not have to be the order shown in FIG. 4, and the three processes may be performed in an arbitrary order, such as performing the processing of step Sb5 first.

[0044] Returning to FIG. 3, when the user desires to add another wireless station device (step Sa4, Yes), the processing after step Sa2 is performed again. On the other hand, when the user does not desire to add another wireless station device (step Sa4, No), the user moves the mouse pointer to the map display button <62> of "■ Obstruction Information" on the execution condition setting screen 41 of FIG. 2 by operating the operation unit 12. When the user performs an operation of pressing the map display button <62> on the operation unit 12, upon receiving an instruction signal from the operation unit 12 due to the operation, the obstruction setting unit <24> is activated.

[0045] (Setting the positions of the start and end points of the obstruction) When activated, the obstacle setting unit 24 reads map data from the map data storage unit 13 and reads data on radio station information from the storage area inside the execution condition setting unit 21. The obstacle setting unit 24 displays on the screen of the display unit 11 an obstacle position setting screen 45-1 shown in FIG. 8 that includes an image of the map represented by the read map data and a station installation position mark 151 corresponding to the read data on radio station information. However, at this point, only the station installation position mark 151 is displayed on the obstacle position setting screen 45-1, and the black circles "●" indicated by reference numerals 152 and 154-1, the white circle "〇" indicated by reference numeral 154-2, and the dotted line indicated by reference numeral 153 are not displayed (step Sa5).

[0046] Note that in the process of step Sa5, when the number of pieces of read radio station information data is one, the obstacle setting unit 24 displays on the obstacle position setting screen 45-1 a map of a range in which the position of the station installation position mark 151 corresponding to the one piece of radio station information data is at the center of the map. When the number of pieces of read radio station information data is plural, the obstacle setting unit 24 displays on the obstacle position setting screen 45-1 a map reduced so as to include all of the plurality of station installation position marks 151 corresponding to each of the plurality of pieces of radio station information data.

[0047] The user operates the operation unit 12 to make the map of a desired area displayed on the obstacle position setting screen 45-1. After considering installing an obstacle on the propagation path of the radio wave transmitted by the radio station device installed at the station installation position mark 151, the user operates the operation unit 12 to move the mouse pointer to a position on the map included in the obstacle position setting screen 45-1, which is the starting point position of the obstacle. When the user performs an operation of selecting the position indicated by the mouse pointer with respect to the operation unit 12, the operation unit 12 detects the coordinates of the selected position in the coordinate system of the screen (step Sa6).

[0048] The operation unit 12 outputs the detected coordinate data to the obstacle setting unit 24. The obstacle setting unit 24 takes in the coordinate data output by the operation unit 12, and based on the map data corresponding to the portion of the map displayed on the screen when the data is taken in, converts the taken-in coordinates from the screen coordinate system to map coordinates to obtain coordinates represented by latitude and longitude. The obstacle setting unit 24 uses the data including the coordinates represented by the obtained latitude and longitude as the data indicating the starting point position of the obstacle.

[0049] The obstacle setting unit 24 displays an obstacle start point mark 152 represented by a black circle "●" at a position corresponding to the starting point of the obstacle on the map of the obstacle position setting screen 45-1 in FIG. 8. The obstacle setting unit 24 displays the numerical value of the latitude of the starting point of the obstacle in the text box for the latitude of the starting point information at the portion indicated by reference numeral 61 on the execution condition setting screen 41 in FIG. 2, and displays the numerical value of the longitude of the starting point of the obstacle in the text box for the longitude of the starting point information (step Sa7).

[0050] When, with the obstacle start point mark 152 displayed on the map of the obstacle position setting screen 45-1, the user performs a drag operation at an arbitrary position on the map with respect to the operation unit 12, the obstacle setting unit 24 receives an instruction signal for the operation from the operation unit 12, and displays the mark of the mouse pointer as a black circle "●" as indicated by reference numeral 154-1, and displays a dotted line segment 153 connecting the displayed black circle "●" of reference numeral 154-1 and the obstacle start point mark 152. When the obstacle setting unit 24 receives the amount of movement obtained by the drag operation from the operation unit 12, it changes the position of the black circle "●" of reference numeral 154-1 according to the received amount of movement, and updates the display of the dotted line segment 153 connecting the black circle "●" of reference numeral 154-1 and the obstacle start point mark 152. Here, assume that the position of the end point of the obstacle desired by the user is the position of the white circle "〇" indicated by reference numeral 154-2. Note that the white circle "〇" indicated by reference numeral 154-2 is shown only for the sake of convenience of explanation and is not displayed on the obstacle position setting screen 45-1.

[0051] Suppose that the drag operation continues and the mouse pointer indicated by reference numeral 154-1 reaches the position of the white circle "〇" indicated by reference numeral 154-2. When the user performs an operation to cancel the drag operation on the operation unit 12, that is, an operation to release the mouse button, the operation unit 12 detects the coordinates in the coordinate system of the screen at the position where the drag operation was canceled (step Sa8).

[0052] The operation unit 12 outputs the detected coordinate data to the obstacle setting unit 24. The obstacle setting unit 24 takes in the coordinate data output by the operation unit 12, and based on the map data corresponding to the portion of the map displayed on the screen when the data is taken in, converts the taken-in coordinates from the screen coordinate system to map coordinates to obtain coordinates represented by latitude and longitude. The obstacle setting unit 24 uses the data including the coordinates represented by the obtained latitude and longitude as data indicating the position of the end point of the obstacle. The obstacle setting unit 24 displays the numerical value of the latitude of the end point of the obstacle in the text box for the latitude of the end point information at the portion indicated by reference numeral 61 on the execution condition setting screen 41 in FIG. 2, and displays the numerical value of the longitude of the end point of the obstacle in the text box for the longitude of the end point information (step Sa9).

[0053] As shown in the obstacle position setting screen 45-1 in FIG. 9, the obstacle setting unit 24 deletes the obstacle start mark 152 and the dotted line segment 153 on the map, and returns the mark of the mouse pointer from the black circle "●" to its original display. The obstacle setting unit 24 displays a line segment 155 indicating the obstacle between the positions of the start point and the end point of the obstacle (step Sa10). Incidentally, in a state where the obstacle position setting screen 45-1 is displayed on the screen of the display unit 11, suppose that the user operates the operation unit 12 to rewrite any of the numerical values displayed in the text boxes for the latitude and longitude of the start point information and the text boxes for the latitude and longitude of the end point information displayed at the portion indicated by reference numeral 61 on the execution condition setting screen 41 in FIG. 2. In this case, the obstacle setting unit 24 takes in the rewritten numerical value and changes the position of the line segment 155 indicating the obstacle displayed on the obstacle position setting screen 45-1 according to the taken-in numerical value.

[0054] When the user operates the operation unit 12, the mouse pointer is moved to the position of the button indicated by the symbol 45-1e on the obstacle position setting screen 45-1. When the user performs an operation of pressing the button corresponding to the position of the mouse pointer on the operation unit 12, the obstacle setting unit 24 receives an instruction signal from the operation unit 12 due to the operation, and closes the obstacle position setting screen 45-1, that is, deletes it from the screen of the display unit 11.

[0055] (Setting the height of the obstacle) The user selects a record corresponding to any one of the radio station devices that he / she wants to affect the propagation of radio waves by the set obstacle from the records displayed in the radio station information table 52 on the execution condition setting screen 41 in FIG. 2. The user moves the mouse pointer to the position of the selected record by operating the operation unit 12. After the user performs an operation of selecting the record corresponding to the position of the mouse pointer on the operation unit 12, the user further moves the mouse pointer to the terrain display button 63 of "■Obstacle Information". When the user performs an operation of pressing the terrain display button 63 on the operation unit 12, the obstacle setting unit 24 is activated again after receiving an instruction signal from the operation unit 12 due to the operation.

[0056] When activated, the obstacle setting unit 24 acquires the local installation position data included in the selected record, that is, the numerical values indicating the latitude and longitude where the wireless station device is installed. The obstacle setting unit 24 acquires the numerical values displayed in the text boxes for the latitude and longitude of each of the start point information and the end point information of the portion indicated by the symbol 61. The obstacle setting unit 24 calculates the latitude and longitude of the midpoint of the obstacle based on the acquired numerical values. The obstacle setting unit 24 generates an image representing the shape of the vertical cross-section of the terrain on a straight line connecting the two points of the position of the latitude and longitude where the wireless station device is installed and the position of the latitude and longitude of the midpoint of the obstacle from the terrain data stored in the terrain data storage unit 14, and including at least the two points and having a certain length. The obstacle setting unit 24 displays the obstacle height setting screen 45-2 shown in FIG. 10 including the generated image of the shape of the vertical cross-section of the terrain (hereinafter, this image is referred to as the vertical cross-section shape 170) on the screen of the display unit 11. The obstacle setting unit 24, for example, displays the vertical cross-section shape 170 on the obstacle height setting screen 45-2 such that the position of the mark 172 indicating the obstacle is at the center position of the vertical cross-section shape 170, and the mark 171 indicating the wireless station device is displayed to the left of the mark 172 indicating the obstacle. The obstacle setting unit 24 displays, on the obstacle height setting screen 45-2, a horizontal axis indicating the distance and a vertical axis indicating the elevation as the coordinate system of the vertical cross-section shape 170 (step Sa11).

[0057] As an operation of the operation unit 12 by the user, assume that the mouse pointer is moved to the mark 172 indicating the obstacle and the mouse is dragged, and the mouse pointer is moved upward. In this case, when the obstacle setting unit 24 receives the amount of movement obtained by the dragging operation from the operation unit 12, it changes the shape of the mark 172 indicating the obstacle by extending it vertically like the mark indicated by the symbol 173 according to the received amount of movement. The vertical length of the shapes of the marks 172 and 173 indicating the obstacle represents the height of the obstacle, and changing the shape by extending it vertically corresponds to increasing the height of the obstacle. The obstacle setting unit 24 changes the vertical length of the mark 172 indicating the obstacle and displays the data of the numerical value indicating the height of the obstacle calculated based on the amount of movement received from the operation unit 12, for example, in units of [m], in the text box of the ground height at the portion indicated by the symbol 65 in the "■ Obstacle Information" of the execution condition setting screen 41 in FIG. 2. As a result, the user can know the detailed height of the obstacle from the numerical value displayed in the text box of the ground height at the portion indicated by the symbol 65 while adjusting the height of the obstacle based on the shape of the terrain on the obstacle height setting screen 45-2.

[0058] When the user finishes the dragging operation, the marks 172 and 173 indicating the obstacle are fixed in the shape at the end of the dragging operation, and the numerical value in the text box of the ground height at the portion indicated by the symbol 65 is also fixed to the numerical value at the end of the dragging operation. In addition, when the height of the obstacle is increased too much, conversely, the height of the obstacle can be lowered by moving the mouse pointer downward in the dragged state, and after the dragging operation is finished, the dragging operation can be performed again to correct the height of the obstacle. When the user operates the operation unit 12 to rewrite the numerical value in the text box of the ground height at the portion indicated by the symbol 65, the obstacle setting unit 24 takes in the rewritten numerical value and increases or decreases the vertical length of the marks 172 and 173 indicating the obstacle displayed on the obstacle height setting screen 45-2 according to the taken-in numerical value.

[0059] When the setting of the height of the obstacle is completed, the user operates the operation unit 12 to move the mouse pointer to the position of the button indicated by the symbol 45-2e on the obstacle height setting screen 45-2. When the user performs an operation of pressing the button corresponding to the position of the mouse pointer on the operation unit 12, the obstacle setting unit 24 receives an instruction signal from the operation unit 12 for this operation and closes the obstacle height setting screen 45-2, that is, deletes it from the screen of the display unit 11. As a result, numerical values are displayed in all the text boxes of "■Obstacle Information" on the execution condition setting screen 41 in FIG. 2, and the obstacle data including the numerical values displayed in these text boxes is completed (step Sa12).

[0060] Here, assume that the user wishes to modify or delete the numerical values displayed in the text boxes of the latitude and longitude of the start point information and the end point information of the part indicated by the symbol 61 on the execution condition setting screen 41 in FIG. 2, and the numerical value displayed in the text box of the ground height of the part indicated by the symbol 65 (step Sa13).

[0061] The process performed when the user wishes to modify these numerical values will be described (step Sa13, modification). When the user modifies the numerical values displayed in the text boxes of the latitude and longitude of the start point information and the end point information respectively, the processes of steps Sa5 to Sa9 are performed again. However, in the process of step Sa5 performed during the modification, the obstacle setting unit 24 acquires the numerical values displayed in the text boxes of the latitude and longitude of the start point information and the end point information of the part indicated by the symbol 61 on the execution condition setting screen 41, and displays the obstacle position setting screen 45-1 in FIG. 9 including the line segment 155 indicating the obstacle displayed at the position corresponding to the acquired numerical value on the screen of the display unit 11.

[0062] In the process of step Sa6 regarding the starting point of the obstacle performed during correction, assuming that the user operates the operation unit 12, first, the mouse pointer is moved to the position of the starting point of the line segment 155 indicating the obstacle. Subsequently, when the user performs a drag operation on the operation unit 12 at this position, the obstacle setting unit 24 receives the movement amount obtained by this drag operation from the operation unit 12, and changes the position of the starting point of the line segment 155 indicating the obstacle according to the received movement amount, and updates the display of the line segment 155 indicating the obstacle. When the user performs an operation to release the drag operation on the operation unit 12, the operation unit 12 detects the coordinates of the position where the drag operation is released in the coordinate system of the screen. The detected coordinates become the coordinates of the position of the new starting point of the obstacle, and then the process of step Sa7 is performed.

[0063] Similarly, in the process of step Sa8 regarding the ending point of the obstacle performed during correction, as an operation of the operation unit 12 by the user, the mouse pointer is moved to the position of the ending point of the line segment 155 indicating the obstacle. After this movement, when the user performs a drag operation on the operation unit 12 at this position, the obstacle setting unit 24 receives the movement amount obtained by this drag operation from the operation unit 12, and changes the position of the ending point of the line segment 155 indicating the obstacle according to the received movement amount, and updates the display of the line segment 155 indicating the obstacle. When the user performs an operation to release the drag operation on the operation unit 12, the operation unit 12 detects the coordinates of the position where the drag operation is released in the coordinate system of the screen. The detected coordinates become the coordinates of the position of the new ending point of the obstacle, and then the process of step Sa9 is performed. Thereby, the starting point and the ending point of the obstacle can be changed on the map. In the case of correction, since the starting point and the ending point of the obstacle have already been set, either one of the starting point and the ending point may be corrected, or both the starting point and the ending point may be corrected. When both are corrected, the starting point may be corrected first and then the ending point, or the ending point may be corrected first and then the starting point.

[0064] In the case of "modification" in step Sa13, if the user modifies the numerical value displayed in the altitude text box of the part indicated by reference numeral 65, the processes of steps Sa11 and Sa12 will be performed again. In the execution condition setting screen 41 of FIG. 2, the user can directly rewrite the numerical values displayed in the text boxes of the latitude and longitude of the start point information and the end point information of the part indicated by reference numeral 61 and the numerical value displayed in the altitude text box of the part indicated by reference numeral 65 by operating the operation unit 12 to modify the positions and heights of the start point and the end point of the obstacle.

[0065] If the user desires to delete the numerical values displayed in the text boxes of the latitude and longitude of the start point information and the end point information of the part indicated by reference numeral 61 and the numerical value displayed in the altitude text box of the part indicated by reference numeral 65 and then perform the obstacle setting again (step Sa13, deletion), the user moves the mouse pointer to the position of the delete button 64 of "■Obstacle Information" on the execution condition setting screen 41 of FIG. 2 by operating the operation unit 12. The user presses the delete button 64 on the operation unit 12, and the operation unit 12 receives an instruction signal from this operation. Then, the obstacle setting unit 24 deletes the numerical values displayed in the text boxes of the latitude and longitude of the start point information and the end point information of the part indicated by reference numeral 61 and the numerical value displayed in the altitude text box of the part indicated by reference numeral 65 (step Sa14). After that, the processes of steps Sa5 to Sa12 for setting the obstacle will be performed. If the user desires neither modification nor deletion, assuming that the creation of the obstacle data is completed (step Sa13, completion), the process proceeds to step Sa15.

[0066] On the execution condition setting screen 41 of FIG. 2, the user operates the operation unit 12 to write characters and numerical values in the text boxes and the like of the remaining items, namely, the items of "■Interference Evaluation Area Setting" and "■Calculation Level Specification". Here, it is assumed that "consideration of attenuation due to terrain" is selected at least in the part indicated by reference numeral 72 of "■Calculation Level Specification" so that the interference evaluation considering the obstacle is performed (step Sa15).

[0067] When the user operates the operation unit 12, the mouse pointer is moved to the calculation execution button 73 on the execution condition setting screen 41. When the user presses the calculation execution button 73 on the operation unit 12, the execution condition setting unit 21 receives an instruction signal from the operation unit 12 due to the operation, and captures and acquires all data such as numerical values and characters displayed on the execution condition setting screen 41. Further, the data of the wireless station information stored in the internal storage area is read out and acquired. The execution condition setting unit 21 writes the acquired data to the storage unit 26. When the writing of the acquired data to the storage unit 26 is completed, the execution condition setting unit 21 activates the interference evaluation unit 25.

[0068] When the interference evaluation unit 25 is activated, it reads out the numerical values of the latitude and longitude of the upper left information and the numerical values of the latitude and longitude of the lower right information written in the four text boxes included in the portion indicated by the symbol 71 of "■ Interference Evaluation Area Setting" on the execution condition setting screen 41 from the storage unit 26. A rectangular area with the position indicated by the numerical values of the latitude and longitude of the upper left information as the upper left and the position indicated by the numerical values of the latitude and longitude of the lower right information as the lower right is set as the evaluation area. The interference evaluation unit 25 divides the evaluation area into a mesh shape including a predetermined number of rectangular meshes, each having the same area. The interference evaluation unit 25 sets each of the meshes generated by dividing the evaluation area into a mesh shape as an evaluation unit area, and sets the coordinates indicating the position of the center of each evaluation unit area in terms of latitude and longitude as the coordinates indicating the position of the evaluation point. The interference evaluation unit 25 reads out the data of the wireless station information from the storage unit 26. Here, it is assumed that there is only one piece of wireless station information data in the storage unit 26, and the following description will be made on the assumption that the interference evaluation unit 25 reads out one piece of wireless station information data.

[0069] The interference evaluation unit 25 reads out data indicating the calculation level designation selected in the portion indicated by the symbol 72 of "[■Calculation Level Designation]" on the execution condition setting screen 41 from the storage unit 26. As described above, the data indicating the calculation level designation read by the interference evaluation unit 25 includes data indicating that "consideration of attenuation due to terrain" has been selected. Therefore, the interference evaluation unit 25 obtains, from the terrain data stored in the terrain data storage unit 14, data indicating the shape of the vertical cross-section of the terrain between the position indicated by the station installation position data included in the read radio station information and the position of each of the plurality of evaluation points, that is, data indicating the change in the elevation of the terrain. The interference evaluation unit 25 reads out obstacle data from the storage unit 26. The interference evaluation unit 25 raises the elevation value by adding the height of the obstacle indicated by the read obstacle data to the elevation values of all positions on the straight line connecting the start point position and the end point position of the obstacle indicated by the read obstacle data, which are the elevation values indicated by the data indicating the shape of the vertical cross-section.

[0070] Based on the position indicated by the station installation position data, the position of any one of the evaluation points, the data of the radio station information other than the station installation position data, the data indicating the shape of the vertical cross-section of the terrain with the elevated elevation corresponding to the evaluation point, and the data indicating the calculation level designation, the interference evaluation unit 25 calculates the interference level at the evaluation point according to a predetermined propagation loss formula. Here, the interference level is, for example, the power level of the radio wave received by the radio station device, which is the interfered station installed at the evaluation point, when the radio station device, which is the interfering station, is installed at the position of the station installation position data included in the data of the radio station information and transmits radio waves according to conditions such as the transmission power set in the data of the radio station information. That is, the larger the value of the interference level, the greater the influence of the interference by the radio wave transmitted by the radio station device. If the value of the interference level is not less than the allowable interference level, necessary wireless communication becomes difficult due to the influence of the interference.

[0071] More specifically, the interference evaluation unit 25 determines whether there is a line of sight between the position indicated by the local installation position data and the position of the evaluation point of the object to be evaluated based on the shape of the vertical cross-section of the terrain with the elevation increased. When the interference evaluation unit 25 determines that there is a line of sight, it calculates the propagation loss using a predetermined propagation loss formula based on the distance between the position indicated by the local installation position data and the position of the evaluation point of the object to be evaluated, the data of the radio station information other than the local installation position data, and the data indicating the calculation level designation, and then calculates the interference level. On the other hand, when the interference evaluation unit 25 determines that there is no line of sight, it calculates the propagation loss using a predetermined propagation loss formula based on the distance between the position indicated by the local installation position data and the position of the evaluation point of the object to be evaluated, the data of the radio station information other than the local installation position data, and the data indicating the calculation level designation, considering the terrain edge obtained from the shape of the vertical cross-section of the terrain with the elevation increased and the loss caused by the edge, and then calculates the interference level. The interference evaluation unit 25 repeats the same operation for all the evaluation points to calculate the interference level for each evaluation point (step Sa16).

[0072] The interference evaluation unit 25 reads out the map data including the evaluation range from the map data storage unit 13. The interference evaluation unit 25 generates a heat map indicating the interference level for each evaluation unit area. For example, the interference evaluation unit 25 classifies the interference level for each evaluation unit area into any one of a plurality of predetermined categories, and selects a color to fill the evaluation unit area corresponding to each evaluation point so that the category with a smaller interference level has a darker color. The interference evaluation unit 25 generates an image in a rectangular shape filled with the selected color for each evaluation unit area, that is, an image of the heat map. The interference evaluation unit 25 generates an image in which the image of the map represented by the read map data is overlaid with the local installation position mark 151 corresponding to the local installation position data, the line segment 155 indicating the obstacle corresponding to the obstacle data, and the image of the generated heat map. The interference evaluation unit 25 displays, as the generated image, for example, the image shown in the interference evaluation result screen 46 shown in FIG. 11 on the screen of the display unit 11 (step Sa17), and ends the process.

[0073] In the interference evaluation result screen 46 shown in FIG. 11, the area indicated by reference numeral 180 is a rectangular evaluation area. For example, the area indicated by reference numeral 181 is one evaluation unit area included in the evaluation area 180. In the example shown in FIG. 11, as an example, an evaluation area 180 including 64 evaluation unit areas is shown. However, the number of evaluation unit areas included in the evaluation area 180 can be arbitrarily determined, and the user may specify different numbers for each calculation of the interference evaluation by the interference evaluation unit 25. As can be seen from FIG. 11, near the local installation position mark 151, the color of the evaluation unit area is light, and it can be seen that the interference level is high, that is, the influence of interference is large. On the other hand, as the distance from the local installation position mark 151 increases, the color of the evaluation unit area gradually becomes darker, and it can be seen that the influence of interference decreases. In this example, since the interfering station at the local installation position mark 151 uses an omnidirectional antenna (omni-antenna), the interference influence situation is as described above. Then, when comparing the color of the evaluation unit area on the side where the local installation position mark 151 exists with the color of the evaluation unit area on the side where the local installation position mark 151 does not exist, based on the position of the line segment 155 indicating the obstacle, it can be seen that the influence of interference by the radio wave transmitted by the radio station device installed at the position of the local installation position mark 151 is greatly reduced due to the presence of the obstacle.

[0074] In the process of step Sa16 described above, in the storage unit 26, there is only one piece of data of wireless station information, and the interference evaluation unit 25 is configured to read one piece of data of wireless station information. On the other hand, when a plurality of pieces of data of wireless station information are stored in the storage unit 26, the interference evaluation unit 25 will read a plurality of pieces of data of wireless station information. In this case, the interference evaluation unit 25 will perform the above-described processing for each combination of each of the plurality of pieces of data of wireless station information and each of the plurality of evaluation points. In this case, since a plurality of interference levels can be obtained at one evaluation point, the interference evaluation unit 25 calculates the interference level at one evaluation point as the sum of the plurality of interference levels obtained at the one evaluation point, and based on the interference levels for each evaluation point, generates and displays a heat map when a plurality of wireless station devices are installed. The interference evaluation unit 25 may generate a heat map other than the heat map shown in FIG. 11, for example, a heat map such as FIG. 21 of Patent Document 1 or FIG. 3 of Non-Patent Document 1.

[0075] In the interference evaluation apparatus 1 of the first embodiment described above, the display unit 11 displays on the screen an image of a map represented by map data created according to a predetermined map coordinate system. The station installation position setting unit 22 converts the position where the user designates to install the wireless station device on the map displayed on the screen into a position in the map coordinate system to obtain station installation position data. The obstacle setting unit 24 sets obstacles on the propagation path of the radio wave transmitted by the wireless station device when the wireless station device is installed according to the station installation position data, and generates obstacle data indicating the positions and heights of both ends of the set obstacles. The obstacle setting unit 24 further converts the positions of both ends of the obstacle designated by the user on the map displayed on the screen into positions in the map coordinate system to obtain data indicating the positions of both ends of the obstacle included in the obstacle data. The interference evaluation unit 25 performs interference evaluation to evaluate the influence of interference caused by the radio wave transmitted by the wireless station device for each of the predetermined evaluation points when the wireless station device is installed according to the station installation position data and the obstacles are installed according to the obstacle data.

[0076] For example, in the technology disclosed in Patent Document 1, the position of the wireless station device is specified by using a screen as shown in FIG. 6 of Patent Document 1. That is, as shown in FIG. 6 of Patent Document 1, the user operates, for example, a computer keyboard to input numerical values indicating the latitude and longitude indicating the position of the wireless station device into the latitude text box and the longitude text box in the third row from the top, thereby specifying the position of the wireless station device. Therefore, it is necessary to investigate and prepare in advance the numerical values of the latitude and longitude of the position where the wireless station device is to be installed, and this work is complicated and time-consuming. When performing interference evaluation, it is not common to set only one position as the position where the wireless station device is to be installed, and it is general to perform a number of positions as candidates for the position where the wireless station device is to be installed. Therefore, the work cost required for investigating, preparing, and further inputting the numerical values of the latitude and longitude of a number of positions becomes enormous.

[0077] On the other hand, in the interference evaluation device 1, on a map, the user can specify the position where the wireless station device is to be installed and obtain the latitude and longitude of the specified position. Therefore, the user does not need to investigate and prepare the latitude and longitude of the wireless station device in advance, and it is possible to reduce the work cost required to align the data related to the position of the wireless station device. In the interference evaluation device 1, when the user specifies the position where the wireless station device is to be installed, a station installation position mark 151 indicating the position of the wireless station device specified by the user is displayed on the map, enabling the position of the specified wireless station device to be presented to the user in a state that is easy to intuitively understand. Since the interference evaluation device 1 performs interference evaluation using the terrain data stored in the terrain data storage unit 14, the user does not need to investigate and prepare in advance the numerical values of the elevations of the terrain around the wireless station device, and it is possible to reduce the work cost required to align the numerical values of the elevations around the wireless station device. When manually investigating and setting the numerical values of the elevations of the terrain around the wireless station device, there is a risk of showing incorrect interference evaluation results due to human errors such as errors in the numerical values obtained through the investigation and setting errors. In contrast, since the interference evaluation device 1 obtains the elevations of the terrain around the wireless station device using the terrain data around the position of the wireless station device when the position of the wireless station device is specified, it is possible to prevent such human errors from occurring.

[0078] In the interference evaluation device 1, on a map, the user designates the positions of the start point and the end point of an obstacle, and obtains the latitude and longitude indicating the positions of the start point and the end point of the designated obstacle. In the interference evaluation device 1, the user designates the height of the obstacle based on the shape of the vertical cross-section of the terrain between the position of the wireless station device and the position of the midpoint of the obstacle. The interference evaluation device 1 adds the height of the obstacle to the elevation of the terrain on the line connecting the start point and the end point of the obstacle designated by the user, raises the elevation, and then performs interference evaluation. Therefore, by using the interference evaluation device 1, it becomes possible to perform interference evaluation after providing an obstacle whose position, length, and height can be arbitrarily changed. By using the result obtained by the interference evaluation, it becomes possible to examine in detail at which position and with what length and height of an obstacle installed, shared use between different wireless communication systems becomes possible.

[0079] In the interference evaluation apparatus 1 of the above-described first embodiment, the terrain data storage unit 14 may be further configured to store in advance building data, which is three-dimensional map data including the height and shape of buildings. Such building data is provided by private map vendors. In this case, when the obstacle setting unit 24 displays the obstacle height setting screen 45-2 in FIG. 10, it will display a shape obtained by adding the shape and height of the building obtained from the building data to the vertical cross-sectional shape 170, and the user will be able to determine the height of the obstacle based on the said shape. Also when the interference evaluation unit 25 calculates the interference level, it will be possible to calculate the interference level considering the shape and height of the building, and it will be possible to obtain a more accurate interference evaluation result. Also in this case, it is not necessary for the user to investigate and prepare in advance the numerical values of the shape and height of the building added to the elevation of the terrain around the radio station apparatus, and the work cost required to align the numerical values of the elevation around the radio station apparatus can be reduced. When storing the building data in advance in the terrain data storage unit 14, in order to be able to select whether to perform interference evaluation using this building data, similar to Patent Documents 1 and 2, a check box for "considering attenuation by buildings" may be provided in the item of "■ calculation level designation" on the execution condition setting screen 41. In the interference evaluation apparatus 1, in the item of "■ calculation level designation" on the execution condition setting screen 41, similar to Patent Documents 1 and 2, a check box for "considering additional loss" and a text box for giving the numerical value of the additional loss may be provided. Note that the additional loss is a certain loss that is uniformly added to the interference level calculated by the interference evaluation unit 25. Therefore, even if only "considering additional loss" is selected, that is, only the check box for "considering additional loss" among the plurality of check boxes in the item of "■ calculation level designation" is selected and the numerical value of the additional loss is written in the text box for "considering additional loss", it will not be possible to evaluate the influence of interference with the obstacles provided in the first embodiment described above. This is because, as described above, it is necessary for the check box for "considering attenuation by terrain" to be selected in order to evaluate the influence of interference with the obstacles provided.However, after setting the obstacles as described above, select the "Consider attenuation due to terrain" checkbox, and furthermore, it is possible to improve the accuracy of interference evaluation by considering several losses. From such a perspective, for example, when it is desired to match the evaluation result with the interference level at the actual measurement site, "Consider additional losses" may be added and selected.

[0080] In the above-described first embodiment, when setting the start and end positions of the obstacle, the obstacle position setting screen 45-1 shown in FIGS. 8 and 9 is used, and when setting the height of the obstacle, the obstacle height setting screen 45-2 shown in FIG. 10 is used. In contrast, on the execution condition setting screen 41, instead of the map display button 62 and the terrain display button 63, one display button may be arranged, and when the display button is selected, the obstacle setting unit 24 may display a single obstacle setting screen that combines the obstacle position setting screen 45-1 and the obstacle height setting screen 45-2 on the screen of the display unit 11. In this case, the user can perform the operation of specifying the start and end points of the obstacle and the operation of specifying the height of the obstacle in parallel on a single obstacle setting screen. In this case, for example, for the operation of specifying the start and end points of the obstacle, the operations shown in steps Sa6 and Sa8 described above may be performed, and for the operation of specifying the height of the obstacle, for example, the scroll wheel of the mouse may be used. The obstacle setting unit 24 changes the vertical length of the marks 172 and 173 indicating the obstacle according to the number of rotations and the rotation angle of the scroll wheel, and calculates the height of the obstacle based on the number of rotations and the rotation angle, and displays a numerical value indicating the calculated height in the text box of the ground height of the part indicated by the symbol 65 of "■Obstacle information" on the execution condition setting screen 41.

[0081] In the above-described first embodiment, with reference to the map displayed on the screen of the display unit 11, the user designates the position of the wireless station device or the positions of the start point and the end point of the obstacle. In contrast, initially, on the execution condition setting screen 41, the user operates the operation unit 12 to write characters or numerical values in the item of "■ Wireless station information" without using the map, write numerical values in the item of "■ Obstacle information" to perform interference evaluation, and upon receiving the result of the interference evaluation, correct the written content only when desired, and correct the data written using the map. As the timing for correction and deletion, for the data of the wireless station information, the timing of step Sb8 in FIG. 4 is shown, and for the obstacle data, the timing of step Sa13 in FIG. 3 is shown. However, these timings are merely examples, and once the data is generated, as long as it is before the operation of pressing the calculation execution button 73 performed in the process of step Sa16, correction and deletion may be performed at any timing. Similarly, for other data given to the interference evaluation apparatus 1 via the text box or the like on the execution condition setting screen 41, once the data is generated, as long as it is before the operation of pressing the calculation execution button 73 performed in the process of step Sa16, correction and deletion can be performed at any timing.

[0082] (Regarding obstacles) In the above-described first embodiment, a specific example of the actual object of the obstacle set by the obstacle setting unit 24 will be described. For example, a concrete structure 190 about 10 m high corresponding to a fence or a wall shown in FIG. 12(a), a structure in which a plurality of transportable panels 191-1 to 191-6 about 10 m high are arranged side by side as shown in FIG. 12(b), and a structure composed of radio wave shielding nets 193-1 to 193-3 which are nets for shielding radio waves shown in FIG. 12(c) and support columns 192-1 to 192-4 for supporting the radio wave shielding nets 193-1 to 193-3 can be used as obstacles. Here, the radio wave shielding nets 193-1 to 193-3 are nets made of an electromagnetic wave shielding material having a mesh structure, for example, as shown in the following references.

[0083] [References: Medical Aid Co., Ltd., "MG Net", [online], [searched on February 18, 2022], Internet <URL: https: / / www.medical-aid.co.jp / products / material / mgnet_emc / index.html >

[0084] Such an electromagnetic wave shielding material with a mesh structure is made of fibers that prevent the transmission of electromagnetic waves for EMC (Electromagnetic Compatibility) countermeasures. Since it allows air to pass through, it is less affected by the wind while being able to shield radio waves.

[0085] The structures shown in FIGS. 12(a) and 12(c) need to be permanently installed. In contrast, the structure shown in FIG. 12(b) is constructed by arranging a plurality of transportable panels 191-1 to 191-6. Therefore, the necessary number of panels can be temporarily installed when needed and removed when no longer needed. However, for the obstacle shown in FIG. 12(b), when installing or removing it, it is necessary to transport the panels 191-1 to 191-6 using a truck or install them using a crane, which requires a lot of time and manpower, resulting in a high installation cost. In contrast, as shown in FIG. 13, by using a plurality of large crane vehicles 195-1 to 195-3 to lift the radio wave shielding net 194 made of the above-described electromagnetic wave shielding material with a mesh structure, an obstacle having the same radio wave shielding performance as the structure in FIG. 12(c) and being transportable can be constructed. For example, as such crane vehicles 195-1 to 195-3, there are tire self-propelled all-terrain cranes that can lift up to about 120 m above the ground.

[0086] The construction method of constructing an obstacle by lifting a radio wave shielding net 194 using a plurality of crane vehicles 195-1 to 195-3 shown in Fig. 13 has the mobility that when an obstacle is needed, it can quickly move to the position where the obstacle is to be installed and install the obstacle. Furthermore, as long as a radio wave shielding net 194 of sufficient size is prepared, it also has the mobility to quickly respond to changes in the width of the obstacle, that is, the length between the starting point and the ending point of the obstacle, and changes in height. Therefore, compared with the obstacle shown in Fig. 12(b), the obstacle shown in Fig. 13 can be installed and removed in a shorter time and the installation cost can be kept low.

[0087] (Specific example of using the interference evaluation device) Next, a specific example of using the interference evaluation device 1 of the first embodiment will be described. Here, the example to be described is a case assuming the shared use of a wireless communication service provided by a wireless station device temporarily installed in a field park when an outdoor event is held in a field park, for example, and a wireless communication service provided by a wireless station device permanently installed in existing facilities around the field park.

[0088] Fig. 14 is a diagram showing an example of a map represented by the map data stored in the map data storage unit 13. In the map, an artificial island 200 which is a landfill is shown. The shape of the artificial island 200 is a shape with a recess, and there are existing port facilities in the area on the right side of the recessed part, that is, the lower right area of Fig. 14. There is a field park where an outdoor event is temporarily held in the area on the left side of the recessed part.

[0089] FIG. 15 is a diagram showing the shape of a vertical cross-section of the terrain on the line of the dashed-dotted line 201 in the map shown in FIG. 14, and buildings and the like existing on the ground. In FIG. 15, the dashed-dotted line 201 corresponds to the dashed-dotted line 201 in FIG. 14, and the shape of the ground 202 shows the shape of the vertical cross-section of the terrain on the line of the dashed-dotted line 201. In the area of the port facility on the right side of FIG. 15, an administrative building 211, a gantry crane 212 used for loading and unloading containers, and a utility pole 213 are constructed, and radio station devices 221-1 and 221-2 for base stations are permanently installed on the utility pole 213. In FIG. 15, the portions indicated by reference numerals 203-1 and 203-2 are the sea, and a ship such as a container ship berths on the side of reference numeral 203-2.

[0090] In the area of the outdoor park on the left side of FIG. 15, utility poles 215 and 216 are constructed, and a temporary stage 214 is constructed for an outdoor event temporarily held. For providing a wireless communication service in the outdoor event, a radio station device 222-1 for a base station is temporarily installed on the utility pole 215, and radio station devices 222-2 and 222-3 for base stations are temporarily installed on the utility pole 216. As shown in FIG. 15, the terrain of the ground 202 has slight undulations near the center that are lower than the height of the multi-story administrative building 211 and is generally flat terrain.

[0091] In this case, if no measures are taken to prevent radio wave interference, the radio waves transmitted by the radio station devices 222-1, 222-2, and 222-3 installed in the country park will reach the terminal station devices carried by people located in the port facility. Therefore, if the radio station devices 222-1, 222-2, and 222-3 temporarily installed in the country park and the radio station devices 221-1 and 221-2 permanently installed in the port facility use the same radio frequency, interference will occur to the terminal station devices carried by people located in the port facility. Using the interference evaluation device 1, identify the position and height of the starting point and ending point of the obstacle 230 installed between the area of the country park and the area of the port facility, which can reduce the interference. That is, regarding the radio station devices 222-1, 222-2, and 222-3 installed in the area of the country park as interfering stations, and setting the area including the country park and the port facility as the evaluation range, the interference evaluation device 1 performs an interference evaluation considering the obstacle 230, the terrain of the ground 202, and the management building 211, gantry crane 212, temporary stage 214, and utility poles 213, 215, and 216, which are buildings on the ground. Repeatedly set the position of the starting point and ending point and the height of the obstacle 230 so that the interference level in the area of the port facility obtained by the interference evaluation by the interference evaluation device 1 becomes the desired interference level. In FIG. 15, as an example of the position where the obstacle 230 finally specified by such a procedure is installed, the position of the undulation with the highest elevation near the center of the artificial island 200 is shown.

[0092] According to the obstacle data of the obstacle 230 identified using the interference evaluation device 1, for example, the crane vehicle 195-1 shown in FIG. 13 is moved to the position of the starting point indicated by the obstacle data, the crane vehicle 195-3 is moved to the position of the ending point indicated by the obstacle data, and the crane vehicle 195-2 is moved to the position of the midpoint between the starting point and the ending point. By lifting the radio wave shielding net 194 having a lateral width equal to or greater than the length between the starting point and the ending point of the obstacle and a vertical width equal to or greater than the height of the obstacle to the height indicated by the obstacle data by means of a crane, the actual obstacle 230 can be temporarily installed. Thereby, the interference generated in the area of the port facility by the radio waves transmitted by the temporarily installed radio station devices 222-1, 222-2, 222-3 can be reduced, and it becomes possible to share and use the temporarily installed radio station devices 222-1, 222-2, 222-3 and the permanently installed radio station devices 221-1, 221-2. In the above example, a port facility is shown as an example of the facility around the country park, but the facility around the country park is not limited to the port facility and may be other facilities such as a seaport airport.

[0093] (Second Embodiment) In the first embodiment, the user designates the position of the radio station device that becomes the interfering station, and the positions and height of the starting point and the ending point of the obstacle. The interference evaluation device 1 evaluates the influence of the interference caused by the radio waves transmitted by the radio station device in consideration of the obstacle installed at the designated positions of the starting point and the ending point and the height. In contrast, in the second embodiment, by designating the position of the radio station device that becomes the interfering station and the interference-affected area in which the influence of the interference caused by the radio waves transmitted by the radio station device is desired to be reduced, the positions and height of both ends of the obstacle that reduce the influence of the interference caused by the radio waves transmitted by the radio station device in the interference-affected area are calculated and presented.

[0094] In other words, in the first embodiment, a problem is set in which the position of the radio station device serving as the interfering station, and the positions and heights of the start and end points of the obstacle are used as inputs, and the range affected by interference is obtained as an output. On the other hand, in the second embodiment, a problem is set in which the position of the radio station device serving as the interfering station and the area to be interfered with whose interference effect is desired to be reduced to a certain interference level are used as inputs, and the positions and heights of both ends of the obstacle that reduces the interference effect on the area to be interfered with to a certain interference level are obtained. In this case, it can be said that the problem of the second embodiment is the inverse problem of the problem of the first embodiment.

[0095] FIG. 16 is a block diagram showing the configuration of the interference evaluation apparatus 1a according to the second embodiment. In the second embodiment, the same components as those in the first embodiment are denoted by the same reference numerals, and different components will be described below.

[0096] The interference evaluation apparatus 1a includes a display unit 11, an operation unit 12, a map data storage unit 13, a terrain data storage unit 14a, and an information processing unit 15a. The terrain data storage unit 14a stores in advance terrain data in which profile data indicating the types of land such as the ground (more specifically, urban areas, residential areas, farmlands, etc.), rivers, seas, mountain forests, and roads is added to the terrain data stored in the terrain data storage unit 14 of the first embodiment. The information processing unit 15a includes an execution condition setting unit 21a, a station installation position setting unit 22, an antenna pattern setting unit 23, an obstacle setting unit 24a, an interference evaluation unit 25a, a storage unit 26a, an area to be interfered with setting unit 31, an interference determination unit 32, and an obstacle determination unit 33.

[0097] The execution condition setting unit 21a has the same configuration as the execution condition setting unit 21 of the first embodiment for components other than the following configuration. When the execution condition setting unit 21 of the first embodiment is activated, the execution condition setting screen 41 in FIG. 2 is displayed on the screen of the display unit 11. On the other hand, when the execution condition setting unit 21a of the second embodiment is activated, the execution condition setting screen 41a shown in FIG. 17 is displayed on the screen of the display unit 11.

[0098] The storage unit 26a stores the data written by the execution condition setting unit 21a. The storage unit 26a stores in advance, in association with the type of obstacle, the value of the weight per unit area of the obstacle for each type of obstacle described with reference to FIGS. 12 and 13. Here, the types of obstacles include, for example, the permanent concrete structure 190 shown in FIG. 12(a), the structure formed by arranging the transportable panels 191-1 to 191-6 shown in FIG. 12(b), and the radio wave shielding nets 193-1 to 193-3 and 194 shown in FIGS. 12(c) and 13.

[0099] The storage unit 26a stores the obstacle condition table 27 shown in FIG. 18. The obstacle condition table 27 has a data format including items such as "obstacle height upper limit value", "obstacle width upper limit value", "obstacle weight upper limit value", "obstacle type", "obstacle height increase ratio", "obstacle approach ratio", "type of land for which obstacle installation is to be avoided", "lower limit value of radio station approach distance", and "initial obstacle height". In the item of "obstacle height upper limit value", a value indicating the upper limit value of the height of the obstacle specified by the user is written, for example, in the unit of [m]. In the item of "obstacle width upper limit value", a value indicating the width of the obstacle specified by the user, that is, the upper limit value of the length between both ends of the obstacle, is written, for example, in the unit of [m]. In the item of "obstacle weight upper limit value", a value indicating the upper limit value of the weight of the obstacle specified by the user is written, for example, in the unit of [kg]. In the item of "obstacle type", the content indicating the type of the obstacle specified by the user is written. Note that the "radio wave shielding net" shown as an example in FIG. 18 indicates that the type of the obstacle is the radio wave shielding nets 193-! to 193-3 and 194 shown in FIGS. 12(c) and 13.

[0100] Suppose that a user intends to install an obstacle by lifting a radio wave shielding net 194 with a crane using crane vehicles 195-1 to 195-3 shown in FIG. 13, for example. In this case, the user will specify "radio wave shielding net" as the type of obstacle. Based on the height to which the radio wave shielding net 194 can be lifted by the crane vehicles 195-1 to 195-3 to be used, the number of available crane vehicles 195-1 to 195-3, and the size of the radio wave shielding net 194 that can be prepared, etc., the upper limit value of the height of the obstacle and the upper limit value of the width of the obstacle will be determined. Since the weight that can be lifted by one crane vehicle is known, the user will determine the upper limit value of the weight of the radio wave shielding net 194 that can be lifted according to the number of crane vehicles 195-1 to 195-3 that can be prepared, that is, the upper limit value of the weight of the obstacle.

[0101] In the obstacle condition table 27, in the item of "obstacle height increase ratio", when the obstacle setting unit 24a re-sets the obstacle, the ratio indicating by what percentage the height of the obstacle is increased compared to the previous time is pre-written in, for example, the unit of "%". In the item of "obstacle approach ratio", when the obstacle setting unit 24a re-sets the obstacle, the ratio indicating by what percentage the distance between the obstacle and the radio station device is reduced to bring the obstacle closer to the radio station device is pre-written in, for example, the unit of "%". In the item of "type of land for which the installation of the obstacle is to be avoided", data indicating the type of land for which the user wants to avoid the installation of the obstacle is pre-written. In the item of "lower limit value of radio station approach distance", when the obstacle setting unit 24a re-sets to bring the obstacle closer to the radio station device, the distance indicating how close the obstacle can be brought is pre-written in, for example, the unit of [m]. In the item of "initial height of obstacle", the value indicating the height of the obstacle set when the obstacle setting unit 24a first sets the obstacle is written by the obstacle setting unit 24a in, for example, the unit of [m].

[0102] The user can define land types such as "rivers" and "seas" within the range of land types shown in the profile data included in the terrain data stored in the terrain data storage unit 14a, where it is considered difficult to install obstacles. The user can define the following distances as the lower limit of the wireless station approach distance. For example, in the case of an outdoor event held in the outdoor park shown as an example in the first embodiment, the closer the obstacle 230 is brought to the wireless station devices 222-1, 222-2, and 222-3 installed in the outdoor park, the more the interference effect in the port facility area can be reduced. However, installing the obstacle 230 in the outdoor park area is likely to divide the event venue or narrow the venue, which is considered unacceptable to the event organizer. Therefore, in this case, it is necessary to determine the lower limit of the wireless station approach distance so that the obstacle 230 does not significantly divide the outdoor park area or narrow the venue.

[0103] In the items of the obstacle condition table 27, the items of "obstacle height upper limit value", "obstacle width upper limit value", "obstacle weight upper limit value", and "obstacle type" are assumed to be specified by the user, and this is specified using the part indicated by the symbol 99 of "■ obstacle condition information" on the execution condition setting screen 41a in FIG. 17. In contrast, the items of "obstacle height increase ratio", "obstacle approach ratio", "land type to avoid installing obstacles", and "lower limit of wireless station approach distance" are assumed to be pre-written in the obstacle condition table 27. Similar to the items of "obstacle height upper limit value", "obstacle width upper limit value", "obstacle weight upper limit value", and "obstacle type", text boxes or the like for specifying the items of "obstacle height increase ratio", "obstacle approach ratio", "land type to avoid installing obstacles", and "lower limit of wireless station approach distance" may be provided in the part indicated by the symbol 99 on the execution condition setting screen 41a so that the user can specify them.

[0104] When an image of a map represented by map data is displayed on the screen of the display unit 11, the interference area setting unit 31 sets, as an interference area, an area surrounded by a plurality of points specified on the map by a user operating the operation unit 12. The interference area setting unit 31 detects, via the operation unit 12, the coordinates of a plurality of points specified by the user in the coordinate system of the screen, and converts each of the coordinates of the detected plurality of points into coordinates in the map coordinate system, that is, latitude and longitude, based on the map data corresponding to the portion of the map displayed on the screen. The interference area setting unit 31 generates, as interference area data, data including the numerical values indicating the latitude and longitude of each of the plurality of points obtained by the conversion and the data indicating the order of connecting the points.

[0105] When performing the initial setting, the obstacle setting unit 24a generates a line segment indicating an obstacle on the propagation path of the radio wave transmitted by the radio station device, which is an interfering station installed at the position indicated by the base station installation position data, between the position indicated by the base station installation position data and the interference area indicated by the interference area data, and specifies the latitude and longitude of the positions at both ends of the generated line segment. When performing the initial setting, the obstacle setting unit 24a sets, as the height of the obstacle, the higher altitude value between the height at which the antenna of the radio station device is installed and the maximum altitude in the interference area obtained from the terrain data stored in the terrain data storage unit 14. The obstacle setting unit 24a generates obstacle data including the latitude, longitude, and height of both ends of the obstacle.

[0106] When the obstacle setting unit 24a receives a reset instruction signal from the interference determination unit 32, it performs resetting of the obstacle so as to reduce the influence of interference by the radio wave transmitted by the radio station device. When the obstacle setting unit 24a receives a reset instruction signal from the obstacle determination unit 33, it performs resetting of the obstacle so as not to meet the obstacle tolerance condition determined by the obstacle determination unit 33.

[0107] The interference evaluation unit 25a has the same configuration as the interference evaluation unit 25 of the first embodiment, except for the following configuration. When the interference evaluation unit 25 of the first embodiment calculates the interference level for each evaluation point, it generates an image of a heat map and displays an interference evaluation result screen 46 shown in FIG. 11 including the generated heat map image on the screen of the display unit 11. In contrast, when the interference evaluation unit 25a of the second embodiment calculates the interference level for each evaluation point, it outputs a determination instruction signal including data of coordinates indicating the position of each evaluation point in latitude and longitude and data indicating the calculated interference level for each evaluation point to the interference determination unit 32.

[0108] The interference determination unit 32 determines whether the interference levels of all the evaluation points included in the interference area among the interference levels for each evaluation point calculated by the interference evaluation unit 25a satisfy the allowable interference level determined by the user.

[0109] The obstacle determination unit 33 determines whether the obstacles set by the obstacle setting unit 24a satisfy the predetermined obstacle allowable conditions. Here, the predetermined obstacle allowable conditions are the conditions defined by the items of "obstacle height upper limit value", "obstacle width upper limit value", "obstacle weight upper limit value", "wireless station approach distance lower limit value", and "type of land where obstacle installation is to be avoided" in the obstacle condition table 27 shown in FIG. 27.

[0110] (Processing by the interference evaluation apparatus according to the second embodiment) FIG. 19 is a flowchart showing the processing flow by the interference evaluation apparatus 1a. In the following, in the first embodiment, in the case where an outdoor event is held in a field park in the artificial island 200 described with reference to FIGS. 14 and 15, the processing of presenting the conditions of the obstacles set by the interference evaluation apparatus 1a according to the second embodiment is shown as an example. However, in FIG. 15, it is assumed that three wireless station devices 222-1, 222-2, and 222-3 are installed in the field park. In the following, an example in which one wireless station device serving as an interfering station is installed in the field park is shown.

[0111] The processes of steps Sc1 to Sc4 are the same as the processes of steps Sa1 to Sa4 in the first embodiment shown in FIG. 3. However, in the first embodiment, the process that was performed by the execution condition setting unit 21 is performed by the execution condition setting unit 21a, and the execution condition setting unit 21a displays the execution condition setting screen 41a in FIG. 17 on the screen of the display unit 11 in the process of step Sc1. As described above, here, in order to show an example of setting the position of one wireless station device, in step Sc4, the user will make a "No" determination. Thereafter, as the process of step Sc5, the subroutine process of the interference area setting process shown in FIG. 20 is performed by the interference area setting unit 31.

[0112] (Setting of the interference area) Proceeding to FIG. 20, the user moves the mouse pointer to the map display button 92 of "■ Interference Area Information" on the execution condition setting screen 41a in FIG. 17 by operating the operation unit 12. When the user presses the map display button 92 with respect to the operation unit 12, the interference area setting unit 31 is activated upon receiving an instruction signal from the operation unit 12 due to this operation. When activated, the interference area setting unit 31 reads out map data from the map data storage unit 13 and reads out data of the wireless station information from the storage area inside the execution condition setting unit 21a. The interference area setting unit 31 displays the interference area setting screen 47 shown in FIG. 23 including the map image represented by the read map data and the station installation position mark 151a corresponding to the data of the read wireless station information on the screen of the display unit 11. However, at this point, only the station installation position mark 151a is displayed on the interference area setting screen 47, and the polygon indicated by the reference numeral 156 and the broken lines indicated by the reference numerals 157-1 to 157-4 are not displayed (step Sd1).

[0113] Here, in the process of step Sd1, the interference area setting unit 31 reads the data of one piece of wireless station information, and thus displays on the interference area setting screen 47 a map of a range where the position of the station installation position mark 151a corresponding to the data of one piece of wireless station information is at the center position of the map. Note that in the process of step Sd1, when the interference area setting unit 31 reads the data of a plurality of pieces of wireless station information, it displays on the interference area setting screen 47 a map reduced so as to include all of the plurality of station installation position marks 151a corresponding to each of the read data of the plurality of pieces of wireless station information.

[0114] The user operates the operation unit 12 to make the map of the port facility area to be set as the interference area displayed on the interference area setting screen 47. The user determines one vertex of the interference area in the shape of a polygon to be at the position of the first vertex. Here, it is assumed that the user determines vertex 156-1 to be at the position of the first vertex. The user operates the operation unit 12 to move the mouse pointer to the position of vertex 156-1. When the user performs an operation of selecting the position indicated by the mouse pointer with respect to the operation unit 12, the operation unit 12 detects the coordinates of the selected position in the coordinate system of the screen (step Sd2).

[0115] The operation unit 12 outputs the detected coordinate data to the interference area setting unit 31. The interference area setting unit 31 takes in the coordinate data output by the operation unit 12, and based on the map data corresponding to the portion of the map displayed on the screen when the data is taken in, converts the taken-in coordinates from the coordinate system of the screen to the map coordinate system to obtain coordinates represented by latitude and longitude. The interference area setting unit 31 sets the data of the coordinates represented by the latitude and longitude obtained by the conversion as the data indicating the position of the first vertex of the interference area. The interference area setting unit 31 assigns the first index to the data of the coordinates of the first vertex represented by latitude and longitude and writes and stores it in the internal storage area (step Sd3).

[0116] The user performs an operation to surround the interfered area, for example, in a clockwise direction, with reference to the first vertex. That is, the user moves the mouse pointer to the position of vertex 156-2, which is the second vertex of the interfered area, by operating the operation unit 12. When the user performs an operation to select the position indicated by the mouse pointer with respect to the operation unit 12, the operation unit 12 detects the coordinates of the selected position in the coordinate system of the screen (step Sd4).

[0117] The operation unit 12 outputs the detected data of the coordinates of the second vertex to the interfered area setting unit 31. The interfered area setting unit 31 takes in the data of the coordinates of the second vertex output by the operation unit 12, and based on the map data corresponding to the portion of the map displayed on the screen when the data is taken in, converts the taken-in coordinates from the coordinate system of the screen to coordinates represented by latitude and longitude (step Sd5).

[0118] The interfered area setting unit 31 determines whether the data of the coordinates of the second vertex obtained by the conversion matches the data of the coordinates of the first vertex stored in the internal storage area (step Sd6). Here, since the data of the coordinates of the second vertex and the data of the coordinates of the first vertex do not match, the interfered area setting unit 31 determines that the data of the coordinates of the second vertex and the data of the coordinates of the first vertex do not match (step Sd6, No). The interfered area setting unit 31 assigns a second index to the data of the coordinates of the second vertex obtained by the conversion and writes and stores it in the internal storage area.

[0119] By repeating the processes of steps Sd4 to Sd6 performed on the second vertex from the third vertex to the seventh vertex indicated by the symbols 156-3, 156-4, 156-5, 156-6, 156-7, which are the vertices of the interfered area, in the internal storage area of the interfered area setting unit 31, data in which each of the positions of the seven vertices of the interfered area is represented by seven coordinate data in terms of latitude and longitude and an index indicating the selected order is assigned to each is stored.

[0120] When the user operates the operation unit 12 to move the mouse pointer to the position indicated by the symbol 156-1 which is the first vertex, and the processes of steps Sd4, Sd5, and Sd6 are performed, here, in the process of step Sd6, the interference area setting unit 31 determines that the data of the coordinates obtained by the conversion matches the data of the coordinates of the first vertex (step Sd6, Yes). As a result, the interference area setting unit 31 determines that the process of surrounding one interference area has ended, and reads out the data of the seven coordinates stored in the internal storage area, to which indexes indicating the selected order are assigned respectively. The interference area setting unit 31 connects the positions indicated by the data of the seven coordinates in the order indicated by the index with straight lines, and displays the interference area frame 156 formed by the connected straight lines on the map of the interference area setting screen 47.

[0121] The interference area setting unit 31 reads out the data of the seven coordinates stored in the internal storage area, to which indexes indicating the selected order are assigned respectively, and uses the read data as interference area data. The interference area setting unit 31 outputs the interference area data to the execution condition setting unit 21a. When the execution condition setting unit 21a takes in the interference area data output by the interference area setting unit 31, it refers to the indexes included in the taken-in interference area data and generates a record in which the data of the seven coordinates are arranged in order from the data of the first coordinate. The execution condition setting unit 21a displays the generated record in the interference area information table 91 of "■ Interference area information" on the execution condition setting screen 41a in FIG. 17 (step Sd7).

[0122] When the user operates the operation unit 12 to move the mouse pointer to the position of the button indicated by the symbol 47e on the interference area setting screen 47. When the user presses the button corresponding to the position of the mouse pointer on the operation unit 12, receiving the instruction signal from the operation unit 12 due to the operation, the interference area setting unit 31 closes the interference area setting screen 47, that is, deletes it from the screen of the display unit 11 (step Sd8).

[0123] Here, it is assumed that the user wishes to modify or delete a record displayed in the interference area information table 91 (step Sd9). When the user wishes to modify a record displayed in the interference area information table 91 (step Sd9, modification), by operating the operation unit 12, the mouse pointer is moved to the position of any one of the records for which modification is desired and which is displayed in the interference area information table 91 of the execution condition setting screen 41a in FIG. 17. After the user performs an operation of selecting the record corresponding to the position of the mouse pointer with respect to the operation unit 12, the mouse pointer is further moved to the map display button 92. When the user performs an operation of pressing the map display button 92 with respect to the operation unit 12, the interference area setting unit 31 is activated upon receiving an instruction signal from the operation unit 12 corresponding to the operation.

[0124] When activated, the interference area setting unit 31 acquires the interference area data, which is the content of the selected record, from the execution condition setting unit 21a, reads the map data from the map data storage unit 13, and reads the data of the wireless station information from the storage area inside the execution condition setting unit 21a. The interference area setting unit 31 displays the interference area setting screen 47 in FIG. 23, which includes the map image represented by the read map data, the station installation position mark 151a corresponding to the data of the read wireless station information, and the interference area frame 156 indicated by the acquired interference area data, on the screen of the display unit 11 (step Sd10).

[0125] The user moves the mouse pointer to the position of any one of the vertices 156-1 to 156-7 whose position in the interference area frame 156 is to be corrected by operating the operation unit 12. When the user performs a drag operation on the operation unit 12 at the said position, the interference area setting unit 31 receives the movement amount obtained by the drag operation from the operation unit 12, changes the position of any one vertex 156-1 to 156-7 to be corrected according to the received movement amount, and updates the display of the interference area frame 156. When the user performs an operation to cancel the drag operation on the operation unit 12, the operation unit 12 detects the coordinates of the position where the drag operation is cancelled in the coordinate system of the screen (step Sd11).

[0126] The operation unit 12 outputs the detected coordinate data to the interference area setting unit 31. The interference area setting unit 31 takes in the coordinate data output by the operation unit 12, converts the taken-in coordinates from the coordinate system of the screen to the map coordinate system to obtain coordinates represented by latitude and longitude. The interference area setting unit 31 rewrites the coordinate data of the vertex to be corrected in the acquired interference area data with the coordinate data obtained by the conversion, and outputs the rewritten interference area data to the execution condition setting unit 21a. When the execution condition setting unit 21a takes in the interference area data output by the interference area setting unit 31, it displays the record generated based on the taken-in interference area data in the interference area information table 91 of "■ Interference area information" on the execution condition setting screen 41a in FIG. 17 (step Sd12). If there are a plurality of vertices to be corrected, the processes of steps Sd11 and Sd12 are repeated, and then the process proceeds to step Sd8.

[0127] When the user wishes to delete a record displayed in the interference area information table 91 (step Sd9, deletion), by operating the operation unit 12, the mouse pointer is moved to the position of any one record in the interference area information table 91 on the execution condition setting screen 41a of FIG. 17 for which deletion is desired. After the user performs an operation to select the record corresponding to the position of the mouse pointer on the operation unit 12, the mouse pointer is further moved to the delete button 93. When the user performs an operation to press the delete button 93 on the operation unit 12, upon receiving an instruction signal from the operation unit 12 due to the operation, the execution condition setting unit 21a deletes the record selected from the interference area information table 91 (step Sd13). Incidentally, when a new interference area is set after the record is deleted, the processing from step Sd1 and subsequent steps will be performed again.

[0128] When the user does not wish to modify or delete, assuming that the creation of the interference area data is completed (step Sd9, completion), the subroutine processing of the interference area setting process ends. Incidentally, when the user sets another interference area, the processing of step Sc5 is further performed, and the subroutine processing of the interference area setting process will be performed.

[0129] (Setting of the allowable interference level) Returning to FIG. 19, by the user operating the operation unit 12, the mouse pointer is moved to the text box for the allowable interference level in the portion indicated by the symbol 95 of "■ Interference area information" on the execution condition setting screen 41a of FIG. 17. When the user performs an operation to select the text box on the operation unit 12, the execution condition setting unit 21 causes a cursor to be displayed in the text box and enables text input. By the user operating the operation unit 12, a numerical value indicating the allowable interference level is written in the text box, for example, in the unit [dBm] (step Sc6).

[0130] (Setting of the obstacle conditions) By operating the operation unit 12, the user moves the mouse pointer to the text box of the "height upper limit value" in the part indicated by the symbol 99 of "■ obstacle condition information" on the execution condition setting screen 41a in FIG. 17. When the user performs an operation of selecting the text box on the operation unit 12, the execution condition setting unit 21 causes a cursor to be displayed in the text box and enables text input. The user writes the upper limit value of the height of the obstacle, for example, in units of [m], into the text box by operating the operation unit 12. By the same operation, the user writes the upper limit value of the width of the obstacle, for example, in units of [m], into the text box of the "width upper limit value" in the part indicated by the symbol 99, and writes the upper limit value of the weight of the obstacle, for example, in units of [kg], into the text box of the "weight upper limit value" in the part indicated by the symbol 99. The user selects one of the obstacle types in the pull-down menu in the part indicated by the symbol 99 by operating the operation unit 12 (step Sc7). The process of step Sc8 is the same as the process of step Sa15 in the first embodiment shown in FIG. 3 and is performed on the execution condition setting screen 41a in FIG. 17.

[0131] By operating the operation unit 12, the user moves the mouse pointer to the obstacle setting button 75 on the execution condition setting screen 41a. When the user performs an operation of pressing the obstacle setting button 75 on the operation unit 12, upon receiving an instruction signal from the operation unit 12 due to the operation, the execution condition setting unit 21a captures and acquires all data such as numerical values and characters displayed on the execution condition setting screen 41a, and further reads and acquires the data of the wireless station information stored in the internal storage area. The execution condition setting unit 21a writes the acquired data into the storage unit 26a.

[0132] When the execution condition setting unit 21a writes a value in the text box for the upper height limit of the part indicated by the symbol 99 in the "■ Obstacle Condition Information" of the execution condition setting screen 41a, it writes the value in the "Upper Obstacle Height Limit" item of the obstacle condition table 27 in the storage unit 26a. Similarly, for the value written in the text box for the upper width limit of the part indicated by the symbol 99, the execution condition setting unit 21a writes the value in the "Upper Obstacle Width Limit" item of the obstacle condition table 27 in the storage unit 26a. For the value written in the text box for the upper weight limit of the part indicated by the symbol 99, the execution condition setting unit 21a writes the value in the "Upper Obstacle Weight Limit" item of the obstacle condition table 27 in the storage unit 26a. For the type of obstacle selected in the pull-down menu of the part indicated by the symbol 99, the execution condition setting unit 21a writes the type in the "Obstacle Type" item of the obstacle condition table 27 in the storage unit 26a. When the writing of the acquired data to the storage unit 26a is completed, the execution condition setting unit 21 activates the obstacle setting unit 24a.

[0133] When the obstacle setting unit 24a is activated, it reads out the data of the wireless station information and the interference area data written in the storage unit 26a. The obstacle setting unit 24a sets a line segment indicating the first obstacle between the position indicated by the station installation position data included in the read wireless station information data and the interference area indicated by the read interference area data. For example, as shown in FIG. 23, four line segments 157-1, 157-2, 157-3, 157-4 that do not pass through the inside of the interference area frame 156 are set from among the seven line segments that can be drawn from the position of the station installation position mark 151a indicated by the position indicated by the station installation position data to the vertices 156-1 to 156-7 of the interference area frame 156. As shown in FIG. 24, the obstacle setting unit 24a sets a line segment 155a-1 with the midpoints of the two outer line segments 157-1 and 157-4 as both ends as the line segment indicating the first obstacle.

[0134] The obstacle setting unit 24a reads out, from the data of the radio station information stored in the storage unit 26a, the numerical value indicating the height at which the antenna of the radio station device written in the text box of the antenna ground height of the portion shown by reference numeral 84-2 in the radio station information editing screen 42 of FIG. 5 is installed. Note that the numerical value indicating the height at which the antenna of the radio station device is installed is represented, for example, in units of [m]. The obstacle setting unit 24a detects the maximum elevation within the range of the interference area frame 156 from the terrain data stored in the terrain data storage unit 14. The obstacle setting unit 24a sets the higher altitude value among the height at which the antenna of the radio station device is installed and the maximum elevation in the interference area as the initial value of the height of the obstacle. The obstacle setting unit 24a writes the initial value of the height of the obstacle, for example, in units of [m], to the item of "obstacle initial height" in the obstacle condition table 27 of the storage unit 26a. The obstacle setting unit 24a generates obstacle data including the latitude and longitude of both ends of the obstacle and the height. The obstacle setting unit 24a writes the generated obstacle data to the storage unit 26a for storage (step Sc9).

[0135] The obstacle setting unit 24a reads out map data from the map data storage unit 13, and displays on the screen of the display unit 11 an obstacle display screen 48 shown in FIG. 24 including the map image represented by the read map data, the station installation position mark 151 corresponding to the station installation position data included in the data of the radio station information, the interference area frame 156 corresponding to the interference area data, and the line segment 155a-1 indicating the obstacle corresponding to the generated obstacle data. Note that in FIG. 24, the line segments 155a-2 and 155a-3 indicating the obstacle are also shown, but these line segments are not displayed at this point. In the obstacle display screen 48, only one line segment indicating the obstacle is displayed, so here, only the line segment 155a-1 is displayed (step Sc10).

[0136] The obstacle setting unit 24a activates the interference evaluation unit 25a. The interference evaluation unit 25a performs the same processing as when it was activated by the execution condition setting unit 21 in step Sa16 of the first embodiment, and calculates the interference level for each evaluation point. The interference evaluation unit 25a outputs a determination instruction signal including data of coordinates indicating the position of each evaluation point in latitude and longitude and data indicating the calculated interference level for each evaluation point to the interference determination unit 32 (step Sc11).

[0137] The interference determination unit 32 captures the determination instruction signal output by the interference evaluation unit 25a, and captures the data of the coordinates of each evaluation point included in the captured determination instruction signal and the data indicating the interference level for each evaluation point. The interference determination unit 32 reads the interfered area data from the storage unit 26a. The interference determination unit 32 extracts all the evaluation points existing within the interfered area frame 156 indicated by the read interfered area data based on the data of the coordinates of each of the captured evaluation points (step Sc12). The interference determination unit 32 reads the data indicating the allowable interference level written in the text box of the allowable interference level of the portion indicated by the code 95 of the execution condition setting screen 41a from the storage unit 26a. The interference determination unit 32 determines whether the interference levels of all the evaluation points within the extracted interfered area frame 156 satisfy the read allowable interference level, that is, whether the interference levels of all the evaluation points within the interfered area frame 156 are less than the allowable interference level (step Sc13).

[0138] When the interference determination unit 32 determines that the interference levels of all the evaluation points are not less than the allowable interference level, in other words, when it determines that the interference level of any one of the evaluation points is equal to or higher than the allowable interference level (step Sc13, No), it outputs a reset instruction signal to the obstacle setting unit 24a. When the obstacle setting unit 24a receives the reset instruction signal from the interference determination unit 32, it starts the subroutine process of the obstacle reset process shown in FIG. 21 (step Sc14).

[0139] (Reset of obstacles (reset instruction from the interference determination unit)) Proceeding to FIG. 21, the obstacle setting unit 24a captures a reset instruction signal (step Se1). The obstacle setting unit 24a determines whether the captured reset instruction signal contains data indicating a determination result (step Se2). Since the reset instruction signal output by the interference determination unit 32 does not contain data indicating a determination result, the obstacle setting unit 24a determines that the reset instruction signal does not contain data indicating a determination result (step Se2, No). The obstacle setting unit 24a reads obstacle data from the storage unit 26a. The obstacle height upper limit value written in the item of "Obstacle height upper limit value" of the obstacle condition table 27 in the storage unit 26a and the obstacle height increase ratio written in the item of "Obstacle height increase ratio" are read. When the obstacle setting unit 24a increases the height of the obstacle indicated by the read obstacle data at a predetermined ratio, that is, the read obstacle height increase ratio, it determines whether the increased height of the obstacle exceeds the obstacle height upper limit value (step Se4).

[0140] When the obstacle setting unit 24a determines that the height of the obstacle increased at a predetermined ratio does not exceed the obstacle height upper limit value (step Se4, No), it sets the obstacle with the height increased at the predetermined ratio as the obstacle to be reset, rewrites the obstacle data stored in the storage unit 26a with the obstacle data indicating the obstacle to be reset, sets the reset result as "OK" (step Se5), and ends the subroutine process of the obstacle reset process.

[0141] On the other hand, when the obstacle setting unit 24a determines that the height of the obstacle increased at a predetermined rate exceeds the upper limit value of the obstacle height (step Se4, Yes), the obstacle setting unit 24a performs a process of moving the obstacle closer to the radio station device. The obstacle setting unit 24a reads out the obstacle approach ratio written in the "obstacle approach ratio" item of the obstacle condition table 27 in the storage unit 26a. Here, assume that the read obstacle approach ratio by the obstacle setting unit 24a is 50% shown as an example in the obstacle condition table 27 of FIG. 18. Here, the position of the obstacle is the position of the line segment 155a-1 indicating the obstacle in FIG. 24. In this case, the obstacle setting unit 24a uses, as the position of one end of the obstacle to be reset, a point obtained by moving the position of one end, which is on the line segment 157-1 among both ends of the line segment 155a-1, closer to the position of the base station installation position mark 151a by a length corresponding to 50% of the length between the position of one end on the line segment 157-1 and the position of the base station installation position mark 151a. Similarly, the obstacle setting unit 24a uses, as the position of the other end of the obstacle to be reset, a point obtained by moving the position of the other end, which is on the line segment 157-4 among both ends of the line segment 155a-1, closer to the position of the base station installation position mark 151a by a length corresponding to 50% of the length between the position of the other end on the line segment 157-4 and the position of the base station installation position mark 151a. As a result, the position of the line segment indicating the obstacle to be reset becomes the position indicated by the line segment 155a-2. The obstacle setting unit 24a sets the data indicating the positions of both ends of the line segment 155a-2 in terms of latitude and longitude as the data of the coordinates indicating the positions of both ends of the obstacle to be reset (step Se6).

[0142] The obstacle setting unit 24a calculates the coordinates of the midpoint of the obstacle to be reset from the data of the coordinates of both ends of the obstacle. The obstacle setting unit 24a calculates the distance between the obstacle to be reset and the radio station device based on the calculated data of the coordinates of the midpoint of the obstacle to be reset and the base station installation position data corresponding to the base station installation position mark 151a. The obstacle setting unit 24a reads out the radio station approach distance lower limit value written in the "radio station approach distance lower limit value" item of the obstacle condition table 27 in the storage unit 26a. The obstacle setting unit 24a determines whether the calculated distance between the obstacle to be reset and the radio station device is equal to or greater than the radio station approach distance lower limit value (step Se7).

[0143] Assume that the obstacle setting unit 24a determines that the calculated distance between the obstacle to be reset and the radio station device is equal to or greater than the lower limit value of the radio station approach distance (step Se7, Yes). In this case, the obstacle setting unit 24a reads out the numerical value indicating the initial obstacle height written in the "Initial Obstacle Height" item of the obstacle condition table 27 in the storage unit 26a, and sets the numerical value indicating the read initial obstacle height as the height of the obstacle to be reset. The obstacle setting unit 24a rewrites the obstacle data stored in the storage unit 26a with the obstacle data indicating the obstacle to be reset, sets the reset result as "OK" (step Se8), and ends the subroutine process of the obstacle reset process.

[0144] On the other hand, when the obstacle setting unit 24a determines that the calculated distance between the obstacle to be reset and the radio station device is less than the lower limit value of the radio station approach distance (step Se7, No), it sets the reset result as "NG" (step Se9) and ends the subroutine process of the obstacle reset process.

[0145] Through the above subroutine process of the obstacle reset process, while the interference level of all evaluation points in the interfered area does not satisfy the allowable interference level, the obstacle setting unit 24a repeatedly receives a reset instruction signal from the interference determination unit 32, and while the height of the obstacle is equal to or less than the upper limit value of the obstacle height, increases the height of the obstacle at a predetermined ratio. When the height of the obstacle exceeds the upper limit value of the obstacle height, as shown in FIG. 24, the obstacle setting unit 24a moves the obstacle closer to the radio station device, resets the height of the obstacle to the initial value, and again performs a process of gradually making the conditions of the obstacle stricter, such as increasing the height of the obstacle at a predetermined ratio. Therefore, while the interference level of all evaluation points in the interfered area does not satisfy the allowable interference level, the position of the obstacle changes in the order of the position of line segment 155a-1, the position of line segment 155a-2, and the position of line segment 155a-3, as shown in FIG. 24. Then, when the distance between the obstacle and the radio station device becomes less than the lower limit value of the radio station approach distance, the obstacle setting unit 24a outputs a reset result "NG" to indicate that an obstacle that satisfies the allowable interference level for all evaluation points in the interfered area cannot be set.

[0146] Returning to FIG. 19, when the obstacle setting unit 24a finishes the subroutine process of the obstacle re-setting process, it determines whether the re-setting result is "OK" or "NG" (step Sc15). When the obstacle setting unit 24a determines that the re-setting result is "OK" (step Sc15, OK), the obstacle data indicating the obstacles re-set in the subroutine process of the obstacle re-setting process is used as new obstacle data, and the processes after step Sc10 are performed. On the other hand, when the obstacle setting unit 24a determines that the re-setting result is "NG" (step Sc15, NG), it displays on the screen of the display unit 11 a message indicating that no obstacle that satisfies the allowable interference level and the obstacle allowable conditions has been obtained (step Sc16), and ends the process.

[0147] On the other hand, in the process of step Sc13, when the interference determination unit 32 determines that the interference levels of all the evaluation points are less than the allowable interference level (step Sc13, Yes), it outputs a determination instruction signal including data indicating the result of the interference evaluation to the obstacle determination unit 33. When receiving the determination instruction signal from the interference determination unit 32, the obstacle determination unit 33 starts the subroutine process of the obstacle allowable condition determination process shown in FIG. 22 (step Sc17).

[0148] (Determination of Obstacle Allowable Conditions) Proceeding to FIG. 22, the obstacle determination unit 33 reads the obstacle data from the storage unit 26a (step Sf1). The obstacle determination unit 33 reads the upper limit value of the obstacle height written in the item of "Upper Limit Value of Obstacle Height" in the obstacle condition table 27 of the storage unit 26a. The obstacle determination unit 33 determines whether the numerical value indicating the height of the obstacle included in the read obstacle data exceeds the read upper limit value of the obstacle height (step Sf2). When the obstacle determination unit 33 determines that the numerical value indicating the height of the obstacle exceeds the upper limit value of the obstacle height (step Sf2, No), it outputs a determination result indicating that it exceeds the upper limit value of the obstacle height and is "NG" (step Sf3), and ends the subroutine process of the obstacle allowable condition determination process.

[0149] On the other hand, when the obstacle determination unit 33 determines that the numerical value indicating the height of the obstacle does not exceed the upper limit value of the obstacle height (step Sf2, Yes), next, the obstacle determination unit 33 calculates the width of the obstacle, which is the length between both ends of the obstacle, from the data of the coordinates of both ends of the obstacle shown in the obstacle data. The upper limit value of the obstacle width written in the item of "upper limit value of obstacle width" in the obstacle condition table 27 of the storage unit 26a is read out. The obstacle determination unit 33 determines whether the numerical value indicating the calculated width of the obstacle exceeds the read upper limit value of the obstacle width (step Sf4). When the obstacle determination unit 33 determines that the numerical value indicating the width of the obstacle exceeds the upper limit value of the obstacle width (step Sf4, No), it outputs a determination result indicating that it exceeds the upper limit value of the obstacle width and is "NG" (step Sf5), and ends the subroutine process of the obstacle allowable condition determination process.

[0150] On the other hand, when the obstacle determination unit 33 determines that the numerical value indicating the width of the obstacle does not exceed the upper limit value of the obstacle width (step Sf4, Yes), next, it multiplies the numerical value indicating the height of the obstacle by the numerical value indicating the width of the obstacle to calculate the area of the obstacle. The obstacle determination unit 33 reads out from the storage unit 26a the weight per unit area corresponding to the type of obstacle written in the item of "type of obstacle" in the storage unit 26a. The obstacle determination unit 33 multiplies the calculated area by the read weight per unit area to calculate the weight of the obstacle. The obstacle determination unit 33 reads out the upper limit value of the obstacle weight written in the item of "upper limit value of obstacle weight" in the obstacle condition table 27 of the storage unit 26a. The obstacle determination unit 33 determines whether the calculated weight of the obstacle exceeds the upper limit value of the obstacle weight (step Sf6). When the obstacle determination unit 33 determines that the calculated weight of the obstacle exceeds the upper limit value of the obstacle weight (step Sf6, No), it outputs a determination result indicating that it exceeds the upper limit value of the obstacle weight and is "NG" (step Sf7), and ends the subroutine process of the obstacle allowable condition determination process.

[0151] On the other hand, when the obstacle determination unit 33 determines that the calculated weight of the obstacle does not exceed the upper limit value of the obstacle weight (step Sf6, Yes), next, the obstacle determination unit 33 calculates the coordinates of the midpoint of the obstacle indicated by the obstacle data from the data of the coordinates of both ends of the obstacle. The obstacle determination unit 33 reads out the station installation position data included in the data of the radio station information from the storage unit 26a. The obstacle determination unit 33 calculates the distance between the obstacle and the radio station device based on the calculated data of the coordinates of the midpoint of the obstacle and the station installation position data. The obstacle determination unit 33 reads out the lower limit value of the radio station approach distance written in the item of "lower limit value of radio station approach distance" in the obstacle condition table 27 of the storage unit 26a. The obstacle determination unit 33 determines whether the calculated distance between the obstacle and the radio station device is less than the lower limit value of the radio station approach distance (step Sf8). When the obstacle determination unit 33 determines that the calculated distance between the obstacle and the radio station device is less than the lower limit value of the radio station approach distance (step Sf8, No), the obstacle determination unit 33 outputs a determination result indicating that it is less than the lower limit value of the radio station approach distance and is "NG" (step Sf9), and ends the subroutine process of the obstacle allowable condition determination process.

[0152] On the other hand, when the obstacle determination unit 33 determines that the calculated distance between the obstacle and the radio station device is not less than the lower limit value of the radio station approach distance (step Sf8, Yes), next, the obstacle determination unit 33 reads out, from the profile data included in the terrain data stored in the terrain data storage unit 14a, data indicating the type of land where the obstacle indicated by the obstacle data is installed. The obstacle determination unit 33 determines whether the type of land where the obstacle indicated by the obstacle data is installed corresponds to the type of land written in the item of "type of land where installation of obstacle is to be avoided" in the obstacle condition table 27 of the storage unit 26a (step Sf10). When the obstacle determination unit 33 determines that the type of land where the obstacle indicated by the obstacle data is installed corresponds to the type of land written in the item of "type of land where installation of obstacle is to be avoided" in the obstacle condition table 27 of the storage unit 26a (step Sf10, No), the obstacle determination unit 33 outputs a determination result indicating that it corresponds to the type of land where installation of obstacle is to be avoided and is "NG" (step Sf11), and ends the subroutine process of the obstacle allowable condition determination process.

[0153] On the other hand, when the obstacle determination unit 33 determines that the type of land where the obstacle indicated by the obstacle data is installed does not correspond to the type of land written in the "Type of land where installation of obstacles is to be avoided" item of the obstacle condition table 27 in the storage unit 26a (step Sf10, Yes), it outputs a determination result "OK" (step Sf12) and ends the subroutine process of the obstacle allowable condition determination process. In the subroutine process of the obstacle allowable condition determination process in FIG. 22, the determination processes in steps Sf2, Sf4, Sf6, Sf8, and Sf10 may be performed in any order.

[0154] Returning to FIG. 19, the obstacle determination unit 33 determines whether the determination result is "OK" or "NG" (step Sc18). When the obstacle determination unit 33 determines that the determination result is "NG" (step Sc18, NG), it outputs a reset instruction signal including data indicating the determination result to the obstacle setting unit 24a. When receiving the reset instruction signal from the obstacle determination unit 33, the obstacle setting unit 24a starts the subroutine process of the obstacle reset process shown in FIG. 21 (step Sc14).

[0155] (Reset of obstacles (reset instruction from the obstacle determination unit)) Proceeding to FIG. 21, the obstacle setting unit 24a fetches the reset instruction signal (step Se1). The obstacle setting unit 24a determines whether the fetched reset instruction signal contains data indicating the determination result (step Se2). Since the reset instruction signal output by the obstacle determination unit 33 contains data indicating the determination result, the obstacle setting unit 24a determines that the reset instruction signal contains data indicating the determination result (step Se2, Yes). The obstacle setting unit 24a reads the obstacle data from the storage unit 26a and adjusts the positions and heights of both ends of the obstacle indicated by the obstacle data according to the data indicating the determination result included in the reset instruction signal.

[0156] For example, when the determination result by the obstacle determination unit 33 indicates that the height of the obstacle exceeds the upper limit value of the obstacle height, rewrite the height of the obstacle data to the upper limit value of the obstacle height written in the "upper limit value of obstacle height" item of the obstacle condition table 27 in the storage unit 26a, and use the obstacle data after the rewrite as the obstacle data indicating the obstacle to be reset. For example, when the determination result by the obstacle determination unit 33 indicates that the width of the obstacle exceeds the upper limit value of the obstacle width, adjust the coordinates of both ends included in the obstacle data so that it becomes equal to or less than the upper limit value of the obstacle width written in the "upper limit value of obstacle width" item of the obstacle condition table 27 in the storage unit 26a, and use the obstacle data after the adjustment as the obstacle data indicating the obstacle to be reset. For example, when the determination result by the obstacle determination unit 33 indicates that the weight of the obstacle exceeds the upper limit value of the obstacle weight, adjust the coordinates of both ends and the height included in the obstacle data so that it becomes equal to or less than the upper limit value of the obstacle weight written in the "upper limit value of obstacle weight" item of the obstacle condition table 27 in the storage unit 26a, and use the obstacle data after the adjustment as the obstacle data indicating the obstacle to be reset. For example, when the determination result by the obstacle determination unit 33 indicates that it is less than the lower limit value of the wireless station approach distance, adjust the coordinates of both ends included in the obstacle data so that it becomes equal to or greater than the lower limit value of the wireless station approach distance written in the "lower limit value of wireless station approach distance" item of the obstacle condition table 27 in the storage unit 26a, and use the obstacle data after the adjustment as the obstacle data indicating the obstacle to be reset. For example, when the determination result by the obstacle determination unit 33 indicates that it corresponds to the type of land where the installation of the obstacle is to be avoided, referring to the terrain data stored in the terrain data storage unit 14a, adjust the coordinates of both ends included in the obstacle data so that the obstacle is not installed on the type of land written in the "type of land where the installation of the obstacle is to be avoided" item of the obstacle condition table 27 in the storage unit 26a, and use the obstacle data after the adjustment as the obstacle data indicating the obstacle to be reset.

[0157] The obstacle setting unit 24a rewrites the obstacle data stored in the storage unit 26a into the obstacle data indicating the obstacle to be reset, sets the reset result as "OK" (step Se3), and ends the subroutine process of the obstacle reset process. Thereafter, the determination process of step Sc15 described above is performed by the obstacle setting unit 24a.

[0158] On the other hand, in the process of step Sc18 in FIG. 19, when the obstacle determination unit 33 determines that the determination result is "OK" (step Sc18, OK), it displays on the screen of the display unit 11 the content of the obstacle data indicating the obstacle to be determined, that is, the numerical values indicating the positions of both ends of the obstacle in latitude and longitude and the numerical value indicating the height of the obstacle. Based on the data indicating the result of the interference evaluation included in the determination instruction signal received from the interference determination unit 32, the obstacle determination unit 33 generates, for example, image data showing the result of the interference evaluation shown in FIG. 11 as a heat map, and displays the image represented by the generated image data on the screen of the display unit 11. Based on the local installation position data stored in the storage unit 26a, the obstacle data, and the terrain data stored in the terrain data storage unit 14a, the obstacle determination unit 33 generates, for example, image data obtained by adding data indicating the position of the radio station device, the position of the midpoint of the obstacle, and the height to the terrain data between the radio station device and the obstacle shown in FIG. 10, and displays the image represented by the generated image data on the screen of the display unit 11 (step Sc19). Note that in the process of step Sc18, the position of the obstacle on the map when the obstacle determination unit 33 makes an "OK" determination has already been displayed on the screen of the display unit 11 in the process of step Sc10. By referring to the screen of the display unit 11, the user can grasp the conditions of the obstacle that satisfy the allowable interference level and the obstacle allowable conditions.

[0159] In the process of FIG. 19 described above, the order of performing the processes of step Sc1 to Sc4 as one set, the process of step Sc5, the process of step Sc6, the process of step Sc7, and the process of step Sc8 does not have to be the order shown in FIG. 19, and the five processes may be performed in an arbitrary order, such as performing the process of step Sc5 first.

[0160] In the interference evaluation apparatus 1a of the second embodiment described above, the interference area setting unit 31 sets an interference area designated by a user and generates interference area data indicating the range of the set interference area. The interference determination unit 32 determines whether or not the result of the interference evaluation performed by the interference evaluation unit 25a for the evaluation points included in the interference area satisfies a predetermined allowable interference level. The obstacle setting unit 24a sets an obstacle at a position between the position indicated by the local installation position data and the interference area indicated by the interference area data, and when the interference determination unit 32 determines that the result of the interference evaluation performed for the evaluation points included in the interference area does not satisfy the allowable interference level, the obstacle is reset so as to reduce the influence of interference by the radio wave transmitted by the radio station apparatus.

[0161] When the flow of the processing in the second embodiment described above is arranged based on the flowchart shown in FIG. 19, for example, it can be arranged as follows. Steps Sc2 to Sc9 are the steps of setting initial conditions. Steps Sc2 to Sc4 are the processes of setting the position of the radio station apparatus as the interfering station and various conditions regarding the radio station apparatus. Steps Sc5 and Sc6 are the processes of setting the interference area and the allowable interference level in the interference area. Step Sc7 is the process of setting the conditions of the obstacle such as the upper limit values of the height and width of the obstacle. Step Sc8 is the process of setting the conditions for the interference evaluation. Step Sc9 is the process of setting the obstacle to be the target of the first interference evaluation.

[0162] Step Sc10 is the process of displaying an obstacle on the map, and step Sc11 is the process of performing an interference evaluation. The processes of steps Sc12 and Sc13 are the processes of determining whether or not the first constraint condition is satisfied. Here, the first constraint condition is the condition that the set obstacle satisfies the allowable interference level in the interference area.

[0163] Steps Sc14 to Sc16 are processes for resetting obstacles. Steps Sc17 to Sc19 are processes for determining whether the second constraint condition is satisfied. Here, the second constraint condition is the condition that the set obstacles satisfy the obstacle allowable conditions.

[0164] That is, in the second embodiment, it can also be interpreted that within the range of the set initial conditions, calculations are performed to calculate the positions and heights of both ends of the obstacles that are solutions satisfying the first constraint condition and the second constraint condition. Therefore, in an environment where wireless communication is used, while performing interference evaluation after providing obstacles whose positions, lengths, and heights can be arbitrarily changed, it is also possible to specify the conditions of the obstacles that satisfy the first constraint condition and the second constraint condition determined by the user.

[0165] In the above second embodiment, as the obstacle allowable conditions that the obstacles, which are the second constraint conditions, should satisfy, "obstacle height upper limit value", "obstacle width upper limit value", "obstacle weight upper limit value", "lower limit value of the proximity distance to the wireless station", and "type of land where the installation of the obstacle is to be avoided" are defined. Among these, "obstacle height upper limit value", "obstacle width upper limit value", and "obstacle weight upper limit value" indirectly indicate the installation cost of the obstacle to be installed. Therefore, it can also be said that the second constraint condition indicates the constraint condition of the installation cost of the obstacle. The amount indicating the installation cost of the obstacle may be directly added as the second constraint condition. In this case, a text box for writing the amount of the installation cost is provided in the portion indicated by reference numeral 99 on the execution condition setting screen 41a in FIG. 17, and the user calculates in advance the amount indicating the installation cost upper limit value and writes the calculated amount indicating the installation cost upper limit value into the text box. The obstacle determination unit 33 calculates the amount required for installing the obstacle from the height and width of the obstacle and determines whether the calculated amount exceeds the installation cost upper limit value.

[0166] In the above-described second embodiment, an example is shown of how to determine the upper limit value of the obstacle weight when the user designates "radio wave shielding net" as the type of obstacle. On the other hand, assume that the user designates as the type of obstacle a heavy obstacle such as the permanent concrete structure 190 shown in Fig. 12(a) or the transportable panels 191-1 to 191-6 shown in Fig. 12(b), and an obstacle for which the ground bearing capacity is important during installation. In this case, the user may, for example, preliminarily investigate the ground bearing capacity of the land where the obstacle may be installed and determine the upper limit value of the obstacle weight per unit area. When the upper limit value of the obstacle weight per unit area is the subject of determination in the obstacle allowable condition determination process of step Sc17, it is necessary as a prerequisite that the depth length of the obstacle is predetermined. The obstacle determination unit 33 calculates the weight of the obstacle from the height and width of the obstacle and the weight per unit area of the obstacle. The obstacle determination unit 33 calculates the weight of the obstacle per unit area on the installation surface based on the installation area of the obstacle on the ground that can be calculated from the length of the width of the obstacle and the predetermined depth length, and determines whether it exceeds the upper limit value of the obstacle weight per unit area.

[0167] In the above-described second embodiment, when the obstacle setting unit 24a performs re-setting of the obstacle, as shown in step Se4 of Fig. 21, while the height of the obstacle does not exceed the upper limit value of the obstacle height written in the "upper limit value of obstacle height" item of the obstacle condition table 27, the height of the obstacle is increased at a predetermined ratio. On the other hand, the obstacle setting unit 24a may, for example, increase the height of the obstacle at a predetermined ratio while not exceeding three times the "initial obstacle height" of the obstacle condition table 27, and when it exceeds three times the "initial obstacle height", proceed to the process of step Se6. Note that three times is just an example, and how many times to set it is appropriately determined according to the type of obstacle and the like.

[0168] In the above-described second embodiment, as shown in step Sc9 of FIG. 19, the obstacle setting unit 24a sets a line segment having the midpoints of each of the two outer line segments 157-1 and 157-4 as both ends as the line segment indicating the first obstacle. As shown in step Se6 of FIG. 21, when the obstacle setting unit 24a re-sets the obstacle, one end of the line segment indicating the obstacle is located on the line of the line segment 157-1, and the other end of the line segment indicating the obstacle is located on the line of the line segment 157-4. In other words, one end of the line segments 155a-1, 155a-2, 155a-3 indicating the obstacles shown in FIG. 24 is located on the line of the line segment 157-1, and the other end of the line segments 155a-1, 155a-2, 155a-3 is located on the line of the line segment 157-4. On the other hand, for example, in the case of the line segment 155a-1, the obstacle setting unit 24a may extend the line segment 155a-1 at each of both ends at a predetermined ratio on the straight line including the line segment 155a-1, and set the coordinates of both ends of the extended line segment 155a-1 as the coordinates of both ends of the obstacle. Instead of determining the extension ratio in advance, the extension ratio may be changed according to the number of times of re-setting the obstacle, such as increasing the extension ratio as the obstacle approaches the wireless station device. In this way, extending the line segments 155a-1, 155a-2, 155a-3 having both ends (starting point and ending point) on the two outermost line segments 157-1 and 157-4 of the line connecting the interference area and the interfering station is not only a simple straight-line propagation of radio waves, but also a countermeasure considering diffraction at the ends of the obstacles. That is, the extension of both ends at the obstacle has the effect of suppressing the influence of interference by the radio wave to be less than the allowable level in the interference area even if the radio wave from the interfering station is diffracted somewhat at both ends of the obstacle. Further, for the first obstacle set in the process of step Sc9, as in the first embodiment, the user may specify the positions of the starting point and the ending point of the obstacle and the height of the obstacle.

[0169] In the above-described second embodiment, as shown in step Se4 of FIG. 21, the obstacle setting unit 24a increases the height of the obstacle at the obstacle height ratio written in the "Obstacle Height Ratio" item of the obstacle condition table 27. In contrast, the obstacle setting unit 24a may, for example, decrease the ratio as the number of times of increasing the height increases. By doing so, as the height of the obstacle increases, the increase in height becomes smaller, and more specifically, the probability of specifying the height of the obstacle that satisfies the allowable interference level can be increased. As shown in step Se6 of FIG. 21, the obstacle setting unit 24a moves the obstacle closer to the radio station device at the obstacle approach ratio written in the "Obstacle Approach Ratio" item of the obstacle condition table 27. In contrast, the obstacle setting unit 24a may, for example, decrease the ratio as the number of times of approaching increases. By doing so, as the obstacle gets closer to the radio station device, the distance that the obstacle moves toward the radio station device becomes shorter, and more specifically, the probability of specifying the positions of both ends of the obstacle that satisfies the allowable interference level can be increased.

[0170] In the above-described second embodiment, as shown in FIG. 18, a river and a sea are shown as an example of the "type of land where installation of an obstacle is to be avoided" in the obstacle condition table 27. In addition to this, for example, the type indicating the landowner, for example, national land, public land, private land, etc. may be specified, or types such as roads and parks may be specified. For example, in the case of the example described with reference to FIGS. 14 and 15 in the first embodiment, if it is land owned by a local government that is the administrator of a field park, or land owned by the operator of a port facility that is affected by interference from radio waves transmitted by a wireless station device installed in the field park, it is considered that it is easy to conduct negotiations for installing an obstacle. On the other hand, if an obstacle is to be installed at a location where a highway exists, it will be necessary to negotiate with the operator of the highway that is not affected by interference from radio waves transmitted by the wireless station device installed in the field park, and it is assumed that the negotiations will be difficult. Therefore, in this case, for example, "roads" including highways may be specified as the "type of land where installation of an obstacle is to be avoided". When specified in this way, even if the interference level of all evaluation points in the interference area satisfies the allowable interference level when the position of the obstacle is set to the position of the line segment 155a-2 indicating the obstacle shown in FIG. 24, since a part of the line segment 155a-2 is located on the road, the obstacle allowable conditions are not satisfied, and the determination result in step Sc18 of FIG. 19 is "NG". Therefore, the obstacle setting unit 24a will reset the obstacle so as to avoid the highway.

[0171] In the above-described second embodiment, the interference evaluation unit 25a divides the area specified in the text box for interference evaluation area setting indicated by reference numeral 71 on the execution condition setting screen 41a in FIG. 17 into a mesh pattern, and sets each of the divided meshes as an evaluation unit area, and performs interference evaluation for each evaluation point set for each evaluation unit area. On the other hand, the interference evaluation unit 25a may, for example, set the smallest rectangular area including the interference area frame 156, divide the area of the set rectangular area into meshes, set each of the divided meshes as an evaluation unit area, and perform interference evaluation for each evaluation point set for each evaluation unit area. By doing so, the number of evaluation points for performing interference evaluation can be reduced, so that the calculation time required for interference evaluation can be shortened.

[0172] In the above-described second embodiment, as shown in step Sc10 of FIG. 19, each time the obstacle setting unit 24a generates new obstacle data, the obstacle data stored in the storage unit 26a is rewritten with the new obstacle data so as to show a line segment indicating an obstacle on the map. On the other hand, the obstacle setting unit 24a stores all the generated obstacle data in the storage unit 26a as a history, and when an obstacle that satisfies the allowable interference level and the obstacle allowable conditions is obtained, in the process of step Sc19, the obstacle data generated by re-setting is arranged and displayed as a history in order from the obstacle data generated first. At that time, line segments corresponding to each of the obstacle data arranged and displayed as a history may be listed and shown on the map. By doing so, it becomes possible for the user to obtain better obstacle data by checking the history and modifying a part of the intermediate obstacle data.

[0173] In the above-described second embodiment, as shown in step Sf6 of FIG. 22, the obstacle determination unit 33 calculates the area of the obstacle by multiplying the value indicating the height of the obstacle by the value indicating the width of the obstacle, and multiplies the calculated area by the weight per unit area read out to calculate the weight of the obstacle. On the other hand, for example, when the type of obstacle specified by the user is "radio wave shielding net", the radio wave shielding nets 193-1 to 193-3 and 194 can shield radio waves even if they are slightly separated from the ground. Therefore, a length that may be separated from the ground is determined in advance and stored in the storage unit 26a in advance, and the obstacle determination unit 33 subtracts the predetermined length from the value indicating the height of the obstacle indicated by the obstacle data, and uses the resulting value as the height of the obstacle to calculate the weight of the obstacle. If the radio wave shielding net can be shortened in the vertical direction in this way, the following becomes possible. Since the shortened portion can be expanded in the horizontal direction, for example, using the same area of radio wave shielding net, the influence of interference can be reduced over a wider range. In addition, by shortening it, the burden of the supporting force against the influence of the wind direction outdoors can be reduced, so it becomes possible to change the vehicle type of the crane vehicle that suspends the radio wave shielding net to a vehicle type with a smaller supporting force. Therefore, since the range of vehicle type selection expands, it becomes possible to easily find a desired crane vehicle from the available crane vehicles.

[0174] In the above-described second embodiment, the timing of step Sd9 in FIG. 20 is shown as the timing for correcting and deleting the interfered area data. However, this timing is an example, and once the interfered area data is generated, as long as it is before the operation of pressing the obstacle setting button 75 performed in the process of step Sc9, the interfered area data may be corrected and deleted at an arbitrary timing. Similarly, for other data given to the interference evaluation device 1a via the execution condition setting screen 41a and the radio station information editing screen 42, once the data is generated, as long as it is before the operation of pressing the obstacle setting button 75 performed in the process of step Sc9, the correction and deletion may be performed at an arbitrary timing.

[0175] In the above-described second embodiment, when explaining the processing of the interference evaluation apparatus 1a shown in FIG. 19, the number of wireless station apparatuses is set to one and the number of interference-affected areas to be set is set to one. However, a plurality of wireless station apparatuses may be set, or a plurality of interference-affected areas may be set. When a plurality of wireless station apparatuses are provided, the interference evaluation unit 25a sums up a plurality of interference levels obtained at one evaluation point as the interference level at one evaluation point, in the same manner as in the first embodiment. The interference evaluation unit 25a generates a heat map when a plurality of wireless station apparatuses are installed based on the interference levels summed up for each evaluation point.

[0176] (Third Embodiment) In the second embodiment, in order to prevent an obstacle from approaching too close to a wireless station apparatus that affects interference, an item "lower limit value of wireless station approach distance" is provided in the obstacle condition table 27 as shown in FIG. 18, and the positions of both ends of the obstacle are set so that the distance between the obstacle and the wireless station apparatus does not become less than the wireless station approach distance shown in the item "lower limit value of wireless station approach distance". On the other hand, in the third embodiment, in order not to reduce the service coverage rate of the communication service provided by the wireless station apparatus, the range of the communication service provided by the wireless station apparatus is predetermined, and the positions and heights of both ends of the obstacle that satisfy the allowable interference level and the obstacle allowable conditions are presented so that no obstacle is installed within the range.

[0177] FIG. 25 is a block diagram showing the configuration of the interference evaluation apparatus 1b according to the third embodiment. In the third embodiment, the same components as those in the first and second embodiments are denoted by the same reference numerals, and different components will be described below.

[0178] The interference evaluation device 1b includes a display unit 11, an operation unit 12, a map data storage unit 13, a terrain data storage unit 14a, and an information processing unit 15b. The information processing unit 15b includes an execution condition setting unit 21b, a base station installation position setting unit 22, an antenna pattern setting unit 23, an obstacle setting unit 24b, an interference evaluation unit 25b, a storage unit 26b, a victim area setting unit 31, an interference determination unit 32, an obstacle determination unit 33b, a communication service providing area setting unit 34, and a communication service ensuring state determination unit 35.

[0179] When an image of a map represented by map data is displayed on the screen of the display unit 11, the communication service providing area setting unit 34 sets, as a communication service providing area, an area surrounded by a plurality of points specified on the map by a user operating the operation unit 12 according to the base station installation position data. The communication service providing area setting unit 34 detects, via the operation unit 12, the coordinates of the plurality of points specified by the user in the coordinate system of the screen, and converts each of the detected coordinates of the plurality of points into coordinates in the map coordinate system, that is, latitude and longitude, based on the map data corresponding to the portion of the map displayed on the screen. The communication service providing area setting unit 34 generates, as communication service providing area data, data including numerical values indicating the latitude and longitude of each of the plurality of points obtained by the conversion and data indicating the order of connecting the points.

[0180] When an obstacle is installed according to the obstacle data, the communication service ensuring state determination unit 35 determines whether the installed obstacle is located in the area indicated by the communication service providing area data, that is, the communication service providing area.

[0181] The execution condition setting unit 21b has the same configuration as the execution condition setting unit 21a in the second embodiment for configurations other than the following. When an operation of pressing the new addition button 53 or the modification button 54 on the execution condition setting screen 41a in FIG. 17 is performed, the execution condition setting unit 21a in the second embodiment, similar to the execution condition setting unit 21 in the first embodiment, displays the wireless station information editing screen 42 in FIG. 5 on the screen of the display unit 11. In contrast, when an operation of pressing the new addition button 53 or the modification button 54 on the execution condition setting screen 41a in FIG. 17 is performed, the execution condition setting unit 21b in the third embodiment displays the wireless station information editing screen 42b shown in FIG. 26 on the screen of the display unit 11.

[0182] The obstacle setting unit 24b has the same configuration as the obstacle setting unit 24a in the second embodiment for configurations other than the following. When re-setting an obstacle, the obstacle setting unit 24a in the second embodiment performs a determination process of determining whether the distance between the obstacle to be re-set and the wireless station device is equal to or greater than the lower limit value of the wireless station approach distance. In contrast, the obstacle setting unit 24b in the third embodiment, instead of the determination process, performs a determination process of determining whether the obstacle to be re-set is not located in the service provision area when re-setting an obstacle.

[0183] The interference evaluation unit 25b has the same configuration as the interference evaluation unit 25 in the first embodiment for configurations other than the following. When the interference evaluation unit 25 in the first embodiment calculates the interference level for each evaluation point, it generates an image of a heat map and displays the interference evaluation result screen 46 shown in FIG. 11 including the generated heat map image on the screen of the display unit 11. In contrast, when the interference evaluation unit 25b in the third embodiment calculates the interference level for each evaluation point, it writes and stores in the storage unit 26b data indicating the range of each evaluation unit area, data of coordinates indicating the position of each evaluation point in latitude and longitude, and data indicating the calculated interference level for each evaluation point. The interference evaluation unit 25b outputs a determination instruction signal including data indicating the range of each evaluation unit area to the communication service assurance state determination unit 35.

[0184] The storage unit 26b stores the data written by the execution condition setting unit 21b. Similar to the storage unit 26a of the second embodiment, the storage unit 26b stores in advance, in association with the type of obstacle, the value of the weight per unit area of the obstacle for each type of obstacle, which was described with reference to FIGS. 12 and 13. The storage unit 26b stores in advance the obstacle condition table 27b shown in FIG. 27. The difference between the obstacle condition table 27 of the second embodiment in FIG. 18 and the obstacle condition table 27b of the third embodiment in FIG. 27 is that the obstacle condition table 27 has an item of "lower limit value of obstacle approach distance", while the obstacle condition table 27b does not have an item of "lower limit value of obstacle approach distance". In other words, the data format of the obstacle condition table 27b is a data format having items excluding the item of "lower limit value of obstacle approach distance" from the items of the obstacle condition table 27.

[0185] The obstacle determination unit 33b has the same configuration as the obstacle determination unit 33 of the second embodiment for configurations other than the following. The obstacle determination unit 33 of the second embodiment performs a determination process of determining whether the distance between the obstacle and the radio station device is less than the lower limit value of the radio station approach distance. In contrast, the obstacle determination unit 33b of the third embodiment is configured not to perform the determination process.

[0186] (Processing by the interference evaluation apparatus of the third embodiment) FIG. 28 is a flowchart showing the flow of processing by the interference evaluation apparatus 1b. Similar to the second embodiment, hereinafter, in the first embodiment, in the case where an outdoor event is held in the artificial island 200 described with reference to FIGS. 14 and 15 in a field park, a process of presenting the conditions of the obstacles to be set by the interference evaluation apparatus 1b of the third embodiment is shown as an example. However, in FIG. 15, it is assumed that three radio station devices 222-1, 222-2, and 222-3 are installed in the field park. Hereinafter, an example of installing one radio station device serving as an interfering station in the field park is shown. Regarding the interfered area, similar to the example shown in the second embodiment, an example of setting one interfered area is shown.

[0187] The processes of steps Sg1 to Sg4 are the same as the processes of steps Sa1 to Sa4 of the first embodiment shown in FIG. 3. However, in the first embodiment, the process that was performed by the execution condition setting unit 21 is performed by the execution condition setting unit 21b. The execution condition setting unit 21b, in the process of step Sg1, displays the execution condition setting screen 41a of FIG. 17 on the screen of the display unit 11, similar to the execution condition setting unit 21a of the second embodiment. As described above, here, in order to show an example of setting the position of one wireless station device, in step Sg4, the user will make a "No" determination.

[0188] (Setting of Communication Service Provision Area) The user moves the mouse pointer to the position of any one record containing the data of the wireless station information displayed in the wireless station information table 52 of the execution condition setting screen 41a of FIG. 17 in which the user wants to set the communication service provision area, by operating the operation unit 12. After the user performs an operation of selecting the record corresponding to the position of the mouse pointer on the operation unit 12, the user further moves the mouse pointer to the correction button 54. When the user performs an operation of pressing the correction button 54 on the operation unit 12, the execution condition setting unit 21b receives an instruction signal from the operation unit 12 due to the operation, and displays the wireless station information editing screen 42b of FIG. 26 on the screen of the display unit 11.

[0189] Subsequently, in the second embodiment, the subroutine process of the interference area setting process by the interference area setting unit 31 described with reference to FIG. 20 is performed as a communication service providing area setting process by the communication service providing area setting unit 34 by being read and replaced as follows. Listing the content to be read and replaced, the interference area is read and replaced with the communication service providing area, the interference area data is read and replaced with the communication service providing area data, the interference area setting unit 31 is read and replaced with the communication service providing area setting unit 34, the execution condition setting unit 21a is read and replaced with the execution condition setting unit 21b, the map display button 92 in FIG. 17 is read and replaced with the map display button 88 in FIG. 26, the delete button 93 in FIG. 17 is read and replaced with the delete button 89 in FIG. 26, the interference area information table 91 in FIG. 17 is read and replaced with the communication service providing area information table 87 in FIG. 26, the interference area setting screen 47 shown in FIG. 23 is read and replaced with the communication service providing area setting screen 49 shown in FIG. 32, and the interference area frame 156 shown in FIG. 23 is read and replaced with the communication service providing area frame 158 shown in FIG. 32.

[0190] The communication service providing area setting process is a process of setting the area of the communication service provided by the radio station device installed according to the station installation position data. In the case of the outdoor event held in the outdoor park of the artificial island 200 described as an example in the first and second embodiments, the communication service providing area is the outdoor park. Therefore, the range of the outdoor park including the station installation position mark 151a as shown in FIG. 32 is set as the communication service providing area frame 158 by the communication service providing area setting unit 34. In the communication service providing area setting process, the communication service providing area setting unit 34 generates communication service providing area data indicating the communication service providing area frame 158. The communication service providing area is an area associated with any one radio station device. Therefore, the communication service providing area data is included in the data of the radio station information corresponding to the radio station device that provides the communication service in the communication service providing area indicated by the communication service providing area data.

[0191] When the communication service providing area setting process performed by the communication service providing area setting unit 34 ends, the user operates the operation unit 12 to move the mouse pointer to the position of the OK button 86 on the wireless station information editing screen 42. When the user operates the operation unit 12 to press the OK button 86 corresponding to the position of the mouse pointer, upon receiving an instruction signal from the operation unit 12 due to the operation, the execution condition setting unit 21b takes in the data of the wireless station information, which is the data given by the user's operation on the wireless station information editing screen 42b, and while storing the taken-in data of the wireless station information in the internal storage area, reflects it also on the execution condition setting screen 41a. The execution condition setting unit 21b closes the wireless station information editing screen 42b, that is, deletes it from the screen of the display unit 11 (step Sg5).

[0192] Here, a method of generating communication service providing area data after generating the data of the wireless station information by the processes of steps Sg1 to Sg4 and adding it to the data of the wireless station information is shown, but the timing of generating the communication service providing area data is not limited to this timing. By the user operating the operation unit 12 to move the mouse pointer to the position of the map display button 88 and selecting the map display button 88 at an arbitrary timing when the wireless station information editing screen 42b in the process of the flowchart shown in FIG. 4 is being displayed on the screen of the display unit 11 and before the operation of pressing the OK button 86 is performed, the communication service providing area setting unit 34 can be activated to generate the communication service providing area data.

[0193] Steps Sg6 to Sg11 perform the same processes as steps Sc5 to Sc10 of the second embodiment shown in FIG. 19. However, the process performed by the execution condition setting unit 21a is performed by the execution condition setting unit 21b, the process performed by the obstacle setting unit 24a is performed by the obstacle setting unit 24b, and the data written to the storage unit 26a is written to the storage unit 26b.

[0194] After the process of step Sg11, the obstacle setting unit 24b activates the interference evaluation unit 25b. The interference evaluation unit 25b performs the same process as when it was activated by the execution condition setting unit 21 in step Sa16 of the first embodiment, and calculates the interference level for each evaluation point. The interference evaluation unit 25b writes and stores in the storage unit 26b the data indicating each range of the evaluation unit area, the data of the coordinates indicating the position of each evaluation point in latitude and longitude, and the data indicating the calculated interference level for each evaluation point. The interference evaluation unit 25b outputs a determination instruction signal including the data indicating each range of the evaluation unit area to the communication service availability determination unit 35 (step Sg12). When receiving the determination instruction signal from the interference evaluation unit 25b, the communication service availability determination unit 35 starts the subroutine process of the communication service availability determination process shown in FIG. 29 (step Sg13).

[0195] (Determination of whether the obstacle is located in the communication service providing area) Proceeding to FIG. 29, the communication service availability determination unit 35 captures the determination instruction signal output by the interference evaluation unit 25b, and reads and acquires the data indicating each range of the evaluation unit area included in the captured determination instruction signal (step Sh1). The communication service availability determination unit 35 reads the communication service providing area data included in the data of the radio station information stored in the storage unit 26b. Based on the data indicating each range of the acquired evaluation unit area and the read communication service providing area data, the communication service availability determination unit 35 extracts the evaluation unit areas having a range overlapping with the range indicated by the communication service providing area data. The communication service availability determination unit 35 writes and stores in the storage unit 26b the data indicating the evaluation unit areas having a range overlapping with the range indicated by the extracted communication service providing area data (step Sh2).

[0196] The communication service availability determination unit 35 reads obstacle data from the storage unit 26b. Based on the data indicating the range of each of the acquired evaluation unit areas and the data of the coordinates at both ends included in the obstacle data, the communication service availability determination unit 35 extracts the evaluation unit areas in which there is a line segment connecting the data of the coordinates at both ends included in the obstacle data (step Sh3).

[0197] The communication service availability determination unit 35 determines whether or not the evaluation unit area extracted for the communication service providing area data and the evaluation unit area extracted for the obstacle data overlap (step Sh4). When the communication service availability determination unit 35 determines that the evaluation unit area extracted for the communication service providing area data and the evaluation unit area extracted for the obstacle data overlap (step Sh4, Yes), it outputs a determination result indicating that there is an overlap in the communication service providing area and it is "NG" (step Sh5), and ends the subroutine processing of the communication service availability determination process.

[0198] On the other hand, when the communication service availability determination unit 35 determines that the evaluation unit area extracted for the communication service providing area data and the evaluation unit area extracted for the obstacle data do not overlap (step Sh4, No), it outputs a determination result of "OK" (step Sh6), and ends the subroutine processing of the communication service availability determination process. In the processing of FIG. 29 above, the processing of step Sh2 and the processing of step Sh3 may be interchanged. That is, the processing of step Sh2 may be performed after the processing of step Sh3.

[0199] Returning to FIG. 28, the communication service assurance state determination unit 35 determines whether the determination result by the subroutine process of the communication service assurance state determination process is "OK" or "NG" (step Sg14). When the communication service assurance state determination unit 35 determines that the determination result is "NG" (step Sg14, NG), it outputs a reset instruction signal including data indicating the determination result to the obstacle setting unit 24b. When receiving the reset instruction signal from the communication service assurance state determination unit 35, the obstacle setting unit 24b starts the subroutine process of the obstacle reset process shown in FIG. 30 (step Sg17).

[0200] (Reset of Obstacles) In the subroutine process of the obstacle reset process shown in FIG. 30, the processes of steps Si1 to Si6, Si8, and Si9 are the same as the processes of steps Se1 to Se6, Se8, and Se9 performed by the obstacle setting unit 24a in the subroutine process of the obstacle reset process of the second embodiment shown in FIG. 21, and are performed by the obstacle setting unit 24b. However, in the case of the process of step Si3, when the determination result included in the reset instruction signal is the determination result by the communication service assurance state determination unit 35 and indicates that there is an overlap in the communication service providing area, the obstacle setting unit 24b performs the following process. The obstacle setting unit 24b reads out the obstacle data from the storage unit 26b and the data indicating the evaluation unit area having an overlapping range with the range indicated by the communication service providing area data. Based on the read data, the obstacle setting unit 24b adjusts the coordinates at both ends included in the obstacle data so that no obstacle is located in the evaluation unit area having an overlapping range with the range indicated by the communication service providing area data, and sets the obstacle data after the adjustment as the obstacle data indicating the obstacle to be reset.

[0201] As the process of step Si7 in the subroutine process of the obstacle re - setting process, the obstacle setting unit 24b performs the following process. That is, the obstacle setting unit 24b reads out the data indicating the range of each evaluation unit area generated by the interference evaluation unit 25b from the storage unit 26b, the obstacle data, and the data indicating the evaluation unit area having a range overlapping with the range indicated by the communication service providing area data. The obstacle setting unit 24b extracts the evaluation unit area in which the line segment connecting the coordinate data at both ends included in the obstacle data exists based on the data indicating the range of each read evaluation unit area and the coordinate data at both ends included in the obstacle data. The communication service ensuring state determination unit 35 determines whether the evaluation unit area having a range overlapping with the range indicated by the communication service providing area data does not overlap with the extracted evaluation unit area for the obstacle data (step Si7). When the communication service ensuring state determination unit 35 determines that the evaluation unit area having a range overlapping with the range indicated by the communication service providing area data does not overlap with the extracted evaluation unit area for the obstacle data (step Si7, Yes), the process proceeds to step Si8. Conversely, when it is determined that they overlap (step Si7, No), the process proceeds to step Si9.

[0202] The processes of steps Sg18 and Sg19 performed after the subroutine process of the obstacle re - setting process are the same as the processes of steps Sc15 and Sc16 performed by the obstacle setting unit 24a in the process of the second embodiment shown in FIG. 19, and are performed by the obstacle setting unit 24b.

[0203] On the other hand, in the process of step Sg14, when the communication service ensuring state determination unit 35 determines that the determination result is "OK" (step Sg14, OK), it reads out the coordinate data indicating the position of each evaluation point in latitude and longitude from the storage unit 26b and the data indicating the interference level for each calculated evaluation point. The communication service ensuring state determination unit 35 outputs a determination instruction signal including the coordinate data indicating the position of each read evaluation point in latitude and longitude and the data indicating the interference level for each calculated evaluation point to the interference determination unit 32. Then, the processes of steps Sg15 and Sg16 are performed.

[0204] The processes of steps Sg15 and Sg16 are the same as the processes of steps Sc12 and Sc13 in the second embodiment shown in FIG. 19, and are performed by the interference determination unit 32. When the interference determination unit 32 determines "No" in step Sg16 (step Sg16, No), a reset instruction signal is output to the obstacle setting unit 24b. Thereafter, as the process of step Sg17, the subroutine process of the obstacle reset process of the third embodiment described above is performed by the obstacle setting unit 24b. On the other hand, when the interference determination unit 32 determines "Yes" in step Sg16 (step Sg16, Yes), a determination instruction signal including data indicating the result of the interference evaluation is output to the obstacle determination unit 33b. When receiving the determination instruction signal from the interference determination unit 32, the obstacle determination unit 33b starts the subroutine process of the obstacle allowable condition determination process shown in FIG. 31 (step Sg20).

[0205] (Determination of Obstacle Allowable Conditions) As described above, the subroutine process of the obstacle allowable condition determination process in the third embodiment shown in FIG. 31 is the same as the process in which the process of steps Sf10 and Sf12 in the subroutine process of the obstacle allowable condition determination process in the second embodiment shown in FIG. 22, which was performed by the obstacle determination unit 33 in the second embodiment, is excluded, and when a "Yes" determination is made in the process of step Sf6, the process of step Sf10 is performed. In other words, the processes of steps Sj1 to Sj7 in FIG. 31 are the same as the processes of steps Sf1 to Sf7 in FIG. 22 and are performed by the obstacle determination unit 33b, and the processes of steps Sj8 to Sj10 in FIG. 31 are the same as the processes of steps Sf10 to Sf12 in FIG. 22 and are performed by the obstacle determination unit 33b. In the subroutine process of the obstacle allowable condition determination process in FIG. 31, the determination processes of steps Sj2, Sj4, Sj6, and Sj8 may be performed in any order.

[0206] The processes of steps Sg21 and Sg22, which are performed after the subroutine process of the obstacle tolerance condition determination process, are the same processes as steps Sc18 and Sc19 performed by the obstacle determination unit 33 in the process of the second embodiment shown in FIG. 19, and are performed by the obstacle determination unit 33b.

[0207] In addition, in the process of FIG. 28 described above, the order of performing the processes of steps Sg1 to Sg5 as one set, the process of step Sg6, the process of step Sg7, the process of step Sg8, and the process of step Sg9 does not have to be the order shown in FIG. 28, and the five processes may be performed in an arbitrary order, such as performing the process of step Sg6 first.

[0208] In the interference evaluation apparatus 1b of the third embodiment described above, the communication service providing area setting unit 34 sets the providing area of the communication service provided by the radio station apparatus installed according to the location data of the station installation position in the area designated by the user, and generates communication service providing area data indicating the range of the set communication service providing area. The communication service ensuring state determination unit 35 determines whether or not the installed obstacle is located in the communication service providing area indicated by the communication service providing area data when an obstacle is installed according to the obstacle data. The obstacle setting unit 24b re-sets the obstacle so that the obstacle is not included in the communication service providing area when the communication service ensuring state determination unit 35 determines that the obstacle is located in the communication service providing area.

[0209] That is, in the third embodiment, it can be interpreted that within the range of the set initial conditions, in addition to the first constraint condition and the second constraint condition, an operation is performed to calculate the positions and heights of both ends of the obstacle that is a solution satisfying the newly set third constraint condition. Here, the third constraint condition is that the obstacle defined as the second constraint condition in the second embodiment satisfies the condition that there is no obstacle in the communication service provision area, instead of the condition that the distance between the radio station device and the obstacle within the condition that the obstacle satisfies the obstacle tolerance condition does not become less than the lower limit value of the radio station approach distance. Thereby, in the third embodiment, in an environment where wireless communication is used, while performing interference evaluation after providing an obstacle whose position, length, and height can be arbitrarily changed, it is possible to specify the conditions of the obstacle that satisfy the first constraint condition, the second constraint condition, and the third constraint condition determined by the user.

[0210] In the above-described third embodiment, the timing of correction and deletion of the communication service provision area data corresponds to the timing of step Sd9 when the interference area setting process in FIG. 20 is read as the process of setting the communication service provision area, but this timing is an example. As long as it is the timing after the communication service provision area data is generated once and before the operation of pressing the obstacle setting button 75 performed in the process of step Sg10, the communication service provision area data may be corrected or deleted at an arbitrary timing. Similarly, for other data given to the interference evaluation device 1b via the execution condition setting screen 41a and the radio station information editing screen 42b, as long as it is the timing after the data is generated once and before the operation of pressing the obstacle setting button 75 performed in the process of step Sg10, it is possible to correct and delete at an arbitrary timing.

[0211] In the above-described third embodiment, when explaining the processing of the interference evaluation apparatus 1b shown in FIG. 28, the number of radio station apparatuses is set to one, the number of interference areas to be set is one, and the number of communication service providing areas to be set is one. However, the number of radio station apparatuses may be plural, a plurality of interference areas may be set, or one or a plurality of communication service providing areas may be set for each radio station apparatus. When the number of radio station apparatuses is plural, as described in the first embodiment, the interference evaluation unit 25b obtains the sum of a plurality of interference levels obtained at one evaluation point as the interference level at the one evaluation point. Then, the interference evaluation unit 25b generates a heat map when a plurality of radio station apparatuses are installed based on the interference levels obtained by summing up the plurality of interference levels for each evaluation point.

[0212] (Another configuration example considering a building (Part 1)) FIG. 33 is a diagram showing a case where a radio station apparatus 301 serving as an interfering station and a radio station apparatus 302 serving as an interfered station are located inside a building 300. As an example of the building 300, for example, a building including a large office room or a building serving as an exhibition hall is assumed. In this case, in addition to the direct wave 310 that directly reaches the radio station apparatus 302 transmitted by the radio station apparatus 301, there are reflected waves 311, 312, and 313 that are reflected by the walls of the building 300 and reach the radio station apparatus 302. Here, the paths of the reflected waves 311, 312, and 313 are shown as an example. The reflected wave 311 is an example of a reflected wave by the ceiling of the building 300, the reflected wave 312 is an example of a reflected wave by the back wall of the building 300, and the reflected wave 313 is an example of a reflected wave by the front wall of the building 300.

[0213] In the case of Fig. 33, when applying the above-described first to third interference evaluation apparatuses 1, 1a, and 1b, it is necessary to provide data indicating the internal structure of the building 300 to the interference evaluation apparatuses 1, 1a, and 1b. The interference evaluation units 25, 25a, and 25b perform interference evaluation based on data indicating the internal structure of the building 300 in addition to the position, length, and height of the obstacle 320 installed in the building 300 and the position of the radio station apparatus 301. In the obstacle 320 shown in Fig. 33, the reflected wave 311 reaching via the ceiling of the building 300 and the reflected wave 312 reaching via the back wall of the building 300 cannot be blocked. Therefore, in the case of the first embodiment, the user uses the interference evaluation apparatus 1 to block the direct wave 310 and the reflected wave 313 and also block the reflected waves 311 and 312 based on the result of the interference evaluation by the interference evaluation unit 25, and specifies the position, length, and height of the obstacle 320 such that the interference level in the area near the radio station apparatus 302 serving as the interfered station satisfies the allowable interference level. In the case of the second and third embodiments, the obstacle setting units 24a and 24b block the direct wave 310 and the reflected wave 313 and also block the reflected waves 311 and 312 based on the result of the interference evaluation by the interference evaluation units 25a and 25b, and specify the position, length, and height of the obstacle 320 such that the interference level in the area near the radio station apparatus 302 serving as the interfered station satisfies the allowable interference level and present them to the user. Note that, as the obstacle 320 used in the case of Fig. 33, for example, in the office of a large room, a partition or the like can be applied, and in the venue of an exhibition, a partition wall of a booth or the like can be applied.

[0214] (Another configuration example considering a building (Part 2)) FIG. 34 is a diagram showing an example in which a radio station device 301a serving as an interfering station is located outdoors, a radio station device 302a serving as an interfered station is located inside a building 300a, and there is an opening 330 such as a window in the building 300a. In this case, it is assumed that in the future, a high frequency band will be used for wireless communication for the radio wave 340 transmitted by the radio station device 301a. The radio wave 340 having such a high frequency is blocked to some extent by the wall of the building 300a, but reaches the radio station device 302a through the opening 330. Therefore, by covering the opening 330 with an obstacle having the same size as the opening 330 and shielding the radio wave 340 near the opening 330, the intrusion of the radio wave 340 into the building 300a can be significantly reduced.

[0215] In the case shown in FIG. 34, when applying the above-described first to third interference evaluation apparatuses 1, 1a, 1b, it is necessary to provide the interference evaluation apparatuses 1, 1a, 1b with data regarding the opening 330 of the building 300a, for example, data indicating the position of the opening 330 in the map coordinate system and the size of the opening 330. The interference evaluation units 25, 25a, 25b perform interference evaluation based on data indicating the position and size of the opening 330 of the building 300a in addition to the position, length, and height of the radio station apparatus 301a and the position of the obstacle 320a. Therefore, in the case of the first embodiment, the user uses the interference evaluation apparatus 1 to determine, based on the result of the interference evaluation by the interference evaluation unit 25, the position, length, and height of the obstacle 320a such that the interference level in the area near the location of the radio station apparatus 302a serving as the interfered station satisfies the allowable interference level. In the case of the second and third embodiments, the obstacle setting units 24a, 24b identify and present to the user the position, length, and height of the obstacle 320a such that the interference level in the area near the location of the radio station apparatus 302a serving as the interfered station satisfies the allowable interference level based on the result of the interference evaluation by the interference evaluation units 25a, 25b. Note that even in the reverse configuration, that is, when the radio station apparatus 301a located indoors is the interfered station and the radio station apparatus 302a located inside the building 300a is the interfering station, the position, length, and height of the obstacle 320a can be identified by the same processing. As an obstacle used in the case of FIG. 34, for example, if it is to be installed permanently, when the opening is a window glass, an obstacle configured by embedding a member that shields radio waves in a mesh shape in the window glass can be applied. On the other hand, if it is to be installed temporarily, an obstacle having a size similar to that of the opening 330 and made of a material that shields radio waves, such as a curtain, blind, partition, or screen, can be applied.

[0216] As the obstacles 320 and 320a in the case shown in FIGS. 33 and 34, the obstacle 400 shown in FIG. 35 may be applied. The obstacle 400 includes a radio wave shielding stretch film 401 that shields radio waves like a screen, a winding unit 402 that winds up the radio wave shielding stretch film 401 like a roller curtain, a support unit 403 that supports the winding unit 402, and casters 404-1 to 404-4 attached to the support unit 403. Therefore, it can be easily moved to a place where the obstacle 400 is to be installed, and an obstacle of any height can be provided within the length range of the radio wave shielding stretch film 401. Therefore, by using the obstacle 400, when it is desired to temporarily install a makeshift obstacle, it becomes easy to install an obstacle whose position, length, and height are changed flexibly according to the influence of interference. Note that the support unit 403 may support the winding unit 402 in the vertical direction so as to expand and contract the radio wave shielding stretch film 401 in the horizontal direction. Instead of the radio wave shielding stretch film 401 and the winding unit 402, each slat (blade) may be applied with a member that shields radio waves and a blind structure that expands and contracts in the vertical direction. Instead of the winding unit 402, a structure like an accordion curtain that opens and closes in the left-right direction with respect to the radio wave shielding stretch film 401 may be applied.

[0217] (Regarding the obstacle installation system) In addition to a plurality of crane vehicles 195-1 to 195-3 shown in FIG. 13 and a radio wave shielding net 194, an apparatus equipped with a communication device is used as an obstacle installation apparatus. When the interference evaluation apparatuses 1, 1a, and 1b of the first to third embodiments can specify the conditions of an obstacle that appropriately reduces the influence of interference by radio waves, the interference evaluation apparatuses 1, 1a, and 1b generate obstacle installation instruction data in which the date and time of installing the obstacle are added to the obstacle data indicating the obstacle. The interference evaluation apparatuses 1, 1a, and 1b transmit the generated obstacle installation instruction data to the communication device of the obstacle installation apparatus via a communication network by a communication unit provided inside with the generated obstacle installation instruction data. By referring to the obstacle installation instruction data received by the communication device, the obstacle installation apparatus can construct an obstacle installation system in which an obstacle having the length and height indicated in the obstacle installation instruction data is installed at the date and time and position indicated in the obstacle installation instruction data. As the obstacle installation apparatus, an apparatus obtained by adding a communication device to the obstacle 400 shown in FIG. 35 may be used. In this case, it becomes possible to construct the above-described obstacle installation system indoors. By constructing such an obstacle installation system, when holding a temporary event as shown in the above-described example or quickly establishing a disaster evacuation shelter due to a disaster, it becomes possible to quickly and easily install an obstacle that reduces the influence of interference by radio waves.

[0218] In the above description, it is assumed that the obstacle installation instruction data displayed on the communication device is referred to by the person driving the crane vehicles 195-1 to 195-3 or the person operating the cranes of the crane vehicles 195-1 to 195-3, and these persons move the crane vehicles 195-1 to 195-3 to install the radio wave shielding net 194, or the obstacle installation instruction data displayed on the communication device is referred to by the person moving the obstacle 400, and this person moves the obstacle 400 to extend the radio wave shielding expandable film 401 to a desired length. However, in the future, if a crane vehicle that autonomously moves and operates the crane according to the obstacle installation instruction data or an obstacle 400 that autonomously moves and extends the radio wave shielding expandable film 401 according to the obstacle installation instruction data is manufactured without human intervention, the interference evaluation devices 1, 1a, and 1b only need to transmit the obstacle installation instruction data to the communication device of the obstacle installation device, and it will be possible to automatically construct an obstacle having a desired length and height at a desired date and time and at a desired position.

[0219] In the first to third embodiments and other configuration examples described above, in the interference evaluation devices 1, 1a, and 1b, the obstacle is represented by a two-dimensional rectangular shape having a set height, which is a line segment connecting the coordinates of both ends of the obstacle. However, since the shape of the obstacle actually installed is an object in three-dimensional space, it will have a thickness. However, it is not necessarily required to have a cuboid shape as shown in Fig. 12(a). Depending on the land division, terrain, etc., it may not be possible to make the shape of the obstacle a cuboid shape, and it may also have a shape with slack like the radio wave shielding nets 193-1 to 193-3 shown in Fig. 12(c) or the radio wave shielding net 194 shown in Fig. 13.

[0220] In the first to third embodiments and other configuration examples described above, the obstacle setting units 24, 24a, and 24b are configured to set one obstacle, but a plurality of obstacles may be installed.

[0221] In the configuration of the above-described embodiment, in the processes shown in step Sc13 of FIG. 19, steps Se3, Se4, Se7 of FIG. 21, steps Sf2, Sf4, Sf6, Sf8 of FIG. 22, step Sg16 of FIG. 28, steps Si3, Si4 of FIG. 30, and steps Sj2, Sj4, Sj6 of FIG. 31, determination processes using inequality signs or inequality signs with equality signs are performed. However, the present invention is not limited to the above embodiment, and the determination processes of "whether it exceeds or not", "whether it is less than or not", "whether it is greater than or equal to or not", and "whether it is less than or equal to or not" are merely examples, and depending on how the threshold value is determined, they may be replaced with the determination processes of "whether it is greater than or equal to or not", "whether it is less than or equal to or not", "whether it exceeds or not", and "whether it is less than or not", respectively.

[0222] The interference evaluation apparatuses 1, 1a, 1b in the above-described embodiment may be realized by a computer. In that case, a program for realizing this function may be recorded on a computer-readable recording medium, and the program recorded on this recording medium may be read into a computer system and executed to realize it. Here, the "computer system" is assumed to include hardware such as an OS and peripheral devices. Also, the "computer-readable recording medium" refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, a CD-ROM, etc., and a storage device such as a hard disk built in a computer system. Further, the "computer-readable recording medium" refers to something that dynamically holds a program for a short time, like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, and may also include something that holds a program for a certain time, like a volatile memory inside a computer system that becomes a server or a client in that case. Also, the above program may be for realizing a part of the above-described function, and may further be realizable in combination with a program already recorded in the computer system for the above-described function, and may also be realized using a programmable logic device such as an FPGA (Field Programmable Gate Array).

[0223] As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and designs and the like within the scope not departing from the gist of the present invention are also included.

Industrial Applicability

[0224] It can be used when evaluating the influence of interference by radio waves.

Explanation of Signs

[0225] 1... Interference evaluation device, 11... Display unit, 12... Operation unit, 13... Map data storage unit, 14... Terrain data storage unit, 15... Information processing unit, 21... Execution condition setting unit, 22... Base station installation position setting unit, 23... Antenna pattern setting unit, 24... Obstacle setting unit, 25... Interference evaluation unit, 26... Storage unit

Claims

1. When the wireless station device is installed according to the station installation position data indicating the position where the user designates and where the wireless station device is to be installed, in the range of terrain and existing buildings different from the obstacles in the propagation path of the radio wave transmitted by the wireless station device, an obstacle setting step of setting obstacles and generating obstacle data indicating the positions and heights of both ends of the set obstacles; An interference evaluation step of performing interference evaluation to evaluate the influence of interference by the radio wave transmitted by the wireless station device for each evaluation point when the wireless station device is installed according to the station installation position data and the obstacles are installed according to the obstacle data; An interference evaluation method including the above.

2. A display step of displaying an image of a map represented by map data created according to a predetermined map coordinate system on a screen; A station installation position setting step of converting the position where the user designates to install the wireless station device on the map displayed on the screen into the position in the map coordinate system to obtain the station installation position data, including: The obstacle setting step includes: Converting the positions of both ends of the obstacle designated by the user on the map displayed on the screen into the positions in the map coordinate system to obtain data indicating the positions of both ends of the obstacle included in the obstacle data; The interference evaluation method according to Claim 1.

3. An interference area setting step of setting an interference area designated by the user and generating interference area data indicating the range of the set interference area; An interference determination step of determining whether the result of the interference evaluation performed on the evaluation points included in the interference area indicated by the interference area data by the interference evaluation step satisfies a predetermined allowable interference level, including: The obstacle setting step includes: Setting the obstacle at a position between the position indicated by the station installation position data and the interference area indicated by the interference area data, and when it is determined by the interference determination step that the result of the interference evaluation performed on the evaluation points included in the interference area does not satisfy the allowable interference level, resetting the obstacle so as to reduce the influence of interference by the radio wave transmitted by the wireless station device; The interference evaluation method according to Claim 1.

4. A communication service providing area setting step of setting a communication service providing area, which is an area designated by a user and is provided by the wireless station device installed according to the local installation position data, and generating communication service providing area data indicating the range of the set communication service providing area; A communication service availability status determination step of determining whether or not the installed obstacle is located in the communication service providing area indicated by the communication service providing area data when the obstacle is installed according to the obstacle data, and The obstacle setting step includes: When it is determined in the communication service availability status determination step that the obstacle is located in the communication service providing area, resetting the obstacle so that the obstacle is not included in the communication service providing area; The interference evaluation method according to claim 3.

5. An obstacle determination step of determining whether or not the obstacle installed according to the obstacle data satisfies a predetermined obstacle tolerance condition, and The obstacle setting step includes: When it is determined in the obstacle determination step that the obstacle does not satisfy the obstacle tolerance condition, resetting the obstacle so that the obstacle satisfies the obstacle tolerance condition; The interference evaluation method according to claim 3 or claim 4.

6. The interference evaluation step includes: When the evaluation point exists inside a building, performing interference evaluation in consideration of the structure of the building; The interference evaluation method according to any one of claims 1 to 5.

7. An obstacle setting unit that, when the wireless station device is installed according to the local installation position data indicating the position where the wireless station device is to be installed, which is a position designated by the user, sets terrain and obstacles different from existing buildings in the range where interference is evaluated on the propagation path of the radio wave transmitted by the wireless station device, and generates obstacle data indicating the positions and heights of both ends of the set obstacles; An interference evaluation unit that performs interference evaluation for each evaluation point to evaluate the influence of interference caused by the radio wave transmitted by the wireless station device when the wireless station device is installed according to the local installation position data and the obstacle is installed according to the obstacle data; An interference evaluation apparatus comprising:

8. The interference evaluation apparatus according to claim 7; and An obstacle installation device that installs a physical object of the obstacle according to the obstacle data generated by the obstacle setting unit of the interference evaluation apparatus. An obstacle installation system comprising:

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