JP2008015572A - Radio wave propagation property calculation device, program, and radio wave propagation property calculation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To calculate physical quantity relating to a radio wave to be transmitted to a reception point with a small processing load even when the shape and arrangement of an obstacle are changed. <P>SOLUTION: When calculating the physical quantity of every propagation path of a radio wave on the basis of data stored in a model data storage region 111 for storing model data in which a transmission point and a reception point and a face to be an obstacle are defined on coordinates, a propagation path from the transmission point to the reception point is stored in a path retrieval data storage region 113 for each face relating to the propagation path, and when any change occurs on an arbitrary face, only the physical quantity of the radio wave to be propagated on the transmission path related by the arbitrary face is recalculated. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a technique for analyzing a state of a radio wave transmitted from a transmitting station.

  Conventionally, as a technique for analyzing the state of radio waves transmitted from a transmitting station, a technique for searching a large number of propagation paths from a transmitting station to a receiving station and analyzing physical quantities related to the radio waves propagated through the respective propagation paths is known. ing.

  For example, in the radio wave propagation characteristic estimation system described in Patent Document 1, a transmission point, a reception point, and an obstacle are arranged on coordinates, and a large number of propagation paths from the transmission point to the reception point are searched. The physical quantity related to the radio wave transmitted to the receiving point is calculated by calculating the influence of the radio wave due to the physical property value of the obstacle at.

JP 2004-304400 A

  However, in the conventional technique, when the shape, arrangement, etc. of the obstacle are changed, the search for the propagation path and the calculation of the physical quantity have to be performed all over again from the beginning, resulting in a heavy processing load and a long processing time.

  Therefore, an object of the present invention is to provide a technique capable of calculating a physical quantity related to a radio wave transmitted to a reception point with a small processing load even when the shape, arrangement, and the like of an obstacle are changed.

  In order to solve the above problems, the present invention stores a propagation path from a transmission point to a reception point for each surface of an obstacle involved in the propagation path. First, a propagation path involving the surface is extracted, and the physical quantity of the radio wave propagated through the extracted propagation path is recalculated.

  For example, the present invention includes a storage unit that stores a transmission point of a radio wave, a reception point of the radio wave, a shape of an obstructing surface, a position of the surface, and physical properties of the surface, and the reception point from the transmission point. A plurality of propagation paths up to, and a calculation unit that calculates, for each propagation path, a physical quantity of radio waves passing through the propagation path, the storage unit including the propagation path Search information for specifying the propagation path involved is stored for each plane involved in the path, and the calculation unit, when the plane is changed, the propagation path related to the changed plane. A process of extracting the search information from the search information, a process of recalculating the propagation path from the transmission point to the reception point via the extracted plane involved in the propagation path, and the recalculated Processing to calculate the physical quantity of radio waves passing through the propagation path , And performs.

  As described above, according to the present invention, since the propagation path from the transmission point to the reception point is stored for each surface of the obstacle involved in the propagation path, when a change occurs in the surface It is only necessary to extract the propagation path related to the surface and recalculate the physical quantity of the radio wave propagated through the extracted propagation path, and the physical quantity can be recalculated with a small processing load.

  FIG. 1 is a schematic diagram of a radio wave propagation characteristic calculation apparatus 100 according to an embodiment of the present invention.

  As illustrated, the radio wave propagation characteristic calculation device 100 includes a storage unit 110, a propagation path calculation unit 120, a physical quantity calculation unit 130, a display processing unit 140, an input unit 150, and a display unit 160. Yes.

  The storage unit 110 includes a model data storage area 111, a propagation path data storage area 112, a path search data storage area 113, a calculation data storage area 114, and a display data storage area 115.

  The model data storage area 111 stores data related to a surface that becomes an obstacle when the propagation path calculation unit 120 described later calculates the propagation path. For example, in the model data storage area 111, surface data 111a (see FIG. 2), shape data 111e (see FIG. 3), physical property data 111h (see FIG. 4), initial information data (not shown), Is memorized.

  Information for identifying a surface that becomes an obstacle is registered in the surface data 111a. The surface data 111a in this embodiment is, for example, a surface for registering a surface ID for uniquely identifying each surface that becomes an obstacle as shown in FIG. 2 (schematic diagram of the surface data 111a). The ID registration column 111b, the shape ID registration column 111c for registering the shape ID for designating data for specifying the shape of the surface specified by the surface ID, and the physical properties of the surface specified by the surface ID A physical property ID registration field 111d for registering physical property IDs for designating data for specifying.

  In the shape data 111e, information for specifying the shape and position of the surface is registered for each shape ID. For example, as shown in FIG. 3 (schematic diagram of the shape data 111e), the shape data 111e in this embodiment includes a coordinate registration field 111f for registering the coordinates of the vertex of the surface for each shape ID, and coordinate registration. A connection destination registration field 111g for specifying the coordinates of the vertexes connected to the vertices registered in the field 111f. Therefore, the shape of the surface can be specified by specifying the vertex and the connection destination vertex.

  In the physical property data 111h, information for specifying the physical property of the surface is registered for each physical property ID. For example, as shown in FIG. 4 (schematic diagram of the physical property data 111h), the physical property data 111h in the present embodiment is a relative permittivity registration for registering the relative permittivity of an object forming a surface for each physical property ID. A column 111i, a relative permeability registration column 111j for registering the relative permeability of the object forming the surface, and a conductivity registration column 111k for registering the conductivity of the object forming the surface.

  That is, a shape ID and a physical property ID are specified for each surface ID in the surface data 111a, a corresponding surface shape is specified by the specified shape ID by the shape data 111e, and a physical property of the corresponding surface is specified by the specified physical property ID. By specifying by 111h, the shape and physical properties of the surface serving as an obstacle are specified for each surface.

  Although not shown in the figure, the model data storage area 111 includes initial information necessary for calculating a transmission point, a reception point, the maximum number of reflections, a propagation path such as a radio wave frequency, and a physical quantity. Stored as data.

  The propagation path data storage area 112 includes calculation point list data 112a (see FIG. 5), calculation point data 112d (see FIG. 6), propagation path data 112g (see FIG. 7), and event point data 112i (FIG. 8). Are stored).

  In the calculation point list data 112a, information for specifying a calculation point that is a radio wave reception point is registered. The calculation point list data 112a in the present embodiment is, for example, as shown in FIG. 5 (schematic diagram of the calculation point list data 112a), a calculation point for registering a calculation point ID for uniquely specifying the calculation point. An ID registration field 112b and a coordinate registration field 112c for specifying the coordinates of the calculation point specified by the calculation point ID are provided.

  In the calculation point data 112d, information for specifying a propagation path of radio waves up to the calculation point is registered for each calculation point which is a radio wave reception point. For example, as shown in FIG. 6 (schematic diagram of the calculation point data 112d), the calculation point data 112d in this embodiment is propagated from the transmission point to the calculation point that is the reception point for each calculation point ID. Register a propagation path ID registration field 112e for registering a propagation path ID for uniquely identifying a path and a determination result of whether the propagation path specified by the propagation path ID is valid or invalid. And a valid / invalid determination registration field 112f.

  In the propagation path data 112g, information for specifying an event point at which a radio wave is reflected, transmitted, diffracted or shielded is registered for each propagation path. For example, as shown in FIG. 7 (schematic diagram of the propagation path data 112g), the propagation path data 112g in the present embodiment is a radio wave in the propagation path specified by the propagation path ID for each propagation path ID. An event point ID registration field 112h for registering an event point ID for uniquely identifying an event point to be reflected, transmitted, diffracted or shielded is provided.

  In the event point data 112i, information for specifying the position and function of the event point is registered for each event point. For example, as shown in FIG. 8 (schematic diagram of the event point data 112i), the event point data 112i in this embodiment includes the coordinates of the event point specified by the event point ID for each event point ID. A coordinate registration field 112j to be registered, an event type registration field for registering an effect on the radio wave at the event point specified by the event point ID (in this embodiment, reflection, transmission, diffraction, or shielding), and an event point ID A surface ID registration field 112l for registering the surface ID of the surface including the event point specified by. When the event point is at the boundary between the surfaces, both surface IDs are registered in the surface ID registration field 112l.

  The route search data storage area 113 stores valid route data 113a and invalid route data 113c.

  The effective path data 113a stores information for identifying a propagation path that is reflected, transmitted, or diffracted by the surface and determined to be effective for each surface. For example, as shown in FIG. 9 (schematic diagram of the effective path data 113a), the effective path data 113a in the present embodiment is reflected, transmitted, or rotated on the surface specified by the surface ID for each surface ID. An effective path ID registration field 113b is provided for registering a propagation path ID that identifies a propagation path that is determined to be valid.

  The invalid path data 113c stores information for specifying a propagation path shielded by the plane for each plane. For example, as shown in FIG. 10 (schematic diagram of invalid route data 113c), the invalid route data 113c in the present embodiment is a propagation route that is shielded by a surface specified by the surface ID for each surface ID. An invalid route ID registration field 113d for registering a propagation route ID for identifying

  Although not shown, the calculation data storage area 114 stores a physical quantity for each propagation path calculated by a physical quantity calculation unit 130 described later.

  The propagation path calculation unit 120 calculates a propagation path from the transmission point to the reception point. Specifically, the propagation path is calculated as follows.

  First, the propagation path calculation unit 120 transmits the transmission point, the reception point, the shape and physical properties of the obstacle surface, the maximum number of reflections, and the frequency of the radio wave from the operator of the radio wave propagation characteristic calculation apparatus 100 via the input unit 150. An input is received, a ray between a transmission point and a reception point is traced by a so-called image method, and a propagation path is calculated.

  For example, for each number of reflections, all combinations of the number of surfaces corresponding to the number of reflections are calculated as event generation order candidates, and a route from the transmission point to the reception point is calculated in order. To do. Such a calculation process can be performed by using a so-called image method or ray tracing method. Then, whether the route calculated in this way is an effective route or an invalid route is determined depending on whether or not the route is blocked by another surface.

  In addition, the propagation path calculation unit 120 calculates a propagation path, and when it is determined to be effective (not blocked by an arbitrary surface), specifies a surface to be reflected, transmitted, or diffracted in the propagation path, and searches for the path. In the data storage area 113, the propagation path ID of the propagation path is registered in the effective path data 113a corresponding to the surface ID of the identified surface. In the case of diffraction, the propagation path ID is registered in the effective path data 113a corresponding to the surface IDs of all the surfaces forming the boundary.

  Further, the propagation path calculation unit 120 calculates a propagation path, and when it is determined to be invalid (shielded by an arbitrary surface), the propagation path calculation unit 120 specifies a surface that shields the propagation path, and stores a route search data storage area. The propagation path ID of the shielded propagation path is registered in the invalid path data 113c corresponding to the surface ID of the identified surface 113.

  In addition, when the propagation path calculation unit 120 receives a surface change from the operator of the radio wave propagation characteristic calculation apparatus 100 via the input unit 150, the propagation path calculation unit 120 includes an effective route and an invalid route corresponding to the surface ID of the changed surface. Is extracted from the effective path data 113a and the invalid path data 113c in the path search data storage area 113, the extracted propagation path is recalculated, the validity / invalidity of the recalculated propagation path is determined, and the propagation path data 112 is determined. The necessary data is registered, and the propagation path ID of the propagation path determined to be valid is sent to the physical quantity calculation unit 130.

  In addition, the recalculation of the extracted propagation path uses the result of extracting the effective path and invalid path corresponding to the surface ID of the changed plane as the recalculation path, and changes the coordinates of the event points included in this recalculation path. This can be done by recalculating in correspondence with the formed surface.

  The physical quantity calculation unit 130 acquires the propagation path ID determined to be valid with reference to the calculation point data 112d in the propagation path data storage area 112, and transmits information on the event point of the acquired propagation path ID to the propagation path data 112g. And the acquired event point coordinates, event type and surface ID are extracted from the event point data 112i.

  Further, the physical property ID corresponding to the surface ID acquired from the event point data 112i is acquired from the surface data 111a, and the relative permittivity, the relative magnetic permeability, and the electrical conductivity corresponding to the acquired physical property ID are extracted from the physical property data 111h.

  Then, the physical quantity calculation unit 130 calculates the physical quantity of the radio wave acquired by propagating the propagation path from the extracted event point coordinates, event type, surface relative permittivity, relative permeability, and conductivity.

  The calculation of the physical quantity may be performed conventionally, but for example, the attenuation amount of the radio wave is calculated as follows.

First, the physical quantity calculation unit 130 calculates the incident angle θ and the emission angle θ of the radio wave to each event point from the transmission point, reception point, and event point of the propagation path for calculating the physical quantity, and reflects it on the surface from the frequency of the radio wave. In order to do so, the reflection coefficient R _TM or R _TE is calculated from the following equation (1) or (2).

  Equation (1) is used when radio waves are TM waves, and equation (2) is used when radio waves are TE waves.

In addition, the physical quantity calculation unit 130 calculates the incident angle θ and the radiation angle θ of the radio wave at each event point, and transmits through the surface from the frequency of the radio wave, the following equation (3) or (4) The transmission coefficient _TTM or _TTE is calculated from the equation.

  The expression (3) is used when the radio wave is a TM wave, and the expression (4) is used when the radio wave is a TE wave.

  Here, the complex refractive index n of the equations (1) to (4) is calculated by the following equation (5).

Further, μ is the magnetic permeability of each surface, ε _r is the relative permittivity of each surface, ε ₀ is the vacuum permittivity, and σ is the conductivity of each surface.

  Further, the physical quantity calculation unit 130 calculates the total distance D from the transmission point of the propagation path for calculating the physical quantity to the reception point via the event point, and calculates the distance attenuation amount L from the following equation (6). Is calculated.

  Here, λ is the wavelength of the radio wave.

  Then, the attenuation amount of the radio wave in the propagation path is calculated by multiplying all the reflection coefficient, transmission coefficient and distance attenuation amount calculated as described above.

  In addition, when the physical quantity calculation unit 130 receives a propagation path ID of a propagation path that has been determined to be valid by recalculation from the propagation path calculation unit 120, the physical quantity of the radio wave that has passed through the propagation path corresponding to the propagation path ID. Is calculated in the same manner as described above.

  The display processing unit 140 generates display data representing the propagation path calculated by the propagation path calculation unit 120 and the physical quantity calculated by the physical quantity calculation unit 130 in a predetermined display format, and displays the display data on the display unit 160 described later. Process.

  For example, for the propagation path calculated by the propagation path calculation unit 120, as shown in FIG. 13 (schematic diagram of display data for displaying the propagation path), the transmission point is a transmission antenna and the reception point is a reception antenna. And each propagation path from the transmitting antenna to the receiving antenna is indicated by an arrow.

  The physical quantity calculated by the physical quantity calculation unit 130 is, for example, as shown in FIG. 14 (schematic diagram of display data displaying the electric field intensity / phase distribution), and the electric field intensity / phase distribution in each propagation path. Is displayed in a coordinate system with the vertical axis representing the imaginary part and the horizontal axis representing the real part, or as shown in FIG. 15 (schematic diagram of display data displaying delay distribution), the delay distribution in each propagation path Is displayed in a coordinate system with the vertical axis representing the electric field strength and the horizontal axis representing the arrival time.

  In the present embodiment, by specifying a specific propagation path in FIG. 13 via an input unit 150 and a display unit 160 (to be described later) (for example, the specific propagation path displayed on the display unit 160 is input to the input unit). The display format such as the color and line shape of the propagation path specified in FIG. 13 is changed, and the physical quantity corresponding to the specified propagation path in FIGS. By changing the display format of the portion for displaying the physical quantity, it is possible to easily grasp the physical quantity corresponding to the specific propagation path.

  In addition, when a specific physical quantity is specified in FIGS. 14 and 15, the display format of the part that displays the specified physical quantity is changed, and in FIG. 13, the propagation path corresponding to the specified physical quantity is changed. The display format of the part to be displayed is changed.

  Further, when the display processing unit 140 receives a change of the surface from the operator of the radio wave propagation characteristic calculation apparatus 100 via the input unit 150 and the display unit 160, the display processing unit 140 displays the fact that the surface has been changed and the changed surface. Information to be identified is notified to the propagation path calculation unit 120.

  The input unit 150 is an input device such as a keyboard or a mouse for inputting data, and the display unit 160 is a coordinate or a calculated propagation path for inputting a transmission point, a reception point, or an obstacle surface. Is a display device such as a display.

  The radio wave propagation characteristic calculation apparatus 100 described above can be configured by a so-called computer.

  For example, the storage unit 110 can be configured by an auxiliary storage device such as a hard disk, and the propagation path calculation unit 120, the physical quantity calculation unit 130, and the display processing unit 140 are configured by an arithmetic device such as a CPU (Central Processing Unit). Is possible.

  Processing for calculating the physical quantity of radio waves in the radio wave propagation characteristic calculation apparatus 100 configured as described above will be described with reference to the flowchart shown in FIG.

  First, the propagation path calculation unit 120 requests the operator of the radio wave propagation characteristic calculation apparatus 100 to input initial information (S170). Here, the initial information includes the transmission point, the reception point, the shape and physical properties of the obstruction surface, the maximum number of reflections R, and the frequency of the radio wave. In addition, regarding the transmission point, the reception point, and the shape of the surface, three-dimensional coordinates are displayed on the display unit 160, and these pieces of information are specified through the input unit 150.

  When the initial information is input (S171), the propagation path calculation unit 120 registers the input initial information in the model data storage area 111 (S172). Specifically, a surface ID is assigned to each input surface and registered in the surface ID registration field 111b of the surface data 111a, and a shape ID is assigned to the shape of this surface and registered in the shape ID registration field 111c. In addition, a physical property ID is assigned to the physical property of the surface and registered in the physical property ID registration field 111d. Then, for the shape specified by the shape ID, the coordinates of the vertex of the surface and the coordinates of the other vertex to which the vertex is connected by the side are registered in the shape data 111e. Further, for the physical property specified by the physical property ID, the relative dielectric constant, the relative magnetic permeability, and the electrical conductivity are registered in the physical property data 111h.

  Further, the transmission point, the reception point, the maximum number of reflections R, and the frequency of the radio wave are stored in the model data storage area 111 as initial information data.

  Then, when the initial information is input, the propagation path calculation unit 120 starts searching for a propagation path.

  First, the propagation path calculation unit 120 determines whether or not the direct waves at the transmission point and the reception point are blocked by the surface (S173). If not shielded (S173), a unique propagation path ID is assigned to the direct wave propagation path, and the effective path ID registration field 113b for all the surface IDs of the effective path data 113a in the path search data storage area 113 is assigned. In addition to registering the direct wave propagation path ID, the necessary information is registered in the propagation path data storage area 112 (S174).

  Here, in the registration to the propagation path data storage area 112, first, a unique calculation point ID is assigned to the reception point input by the operator, and the calculation point ID and the coordinates of the reception point are registered in the calculation point list data 112a. To do. Then, the calculation point data 112d related to the calculation point ID is generated, the direct wave propagation path ID is registered, and the identification code indicating “valid” is registered. Further, when the direct wave passes through the surface, a point on the surface to be transmitted is specified, a unique event point ID is assigned as the event point, and propagation path data is related to the propagation path ID. The event point coordinates, the identification code indicating the transmission, and the surface ID of the surface including the event point are registered in the event point data 112i in association with the event point ID. When the direct wave is diffracted, a point on the surface to be diffracted is specified, a unique event point ID is assigned to the point as an event point, and propagation path data is associated with the propagation path ID. The event point data includes the event point coordinates, the identification code indicating the diffraction, and the surface ID (in this case, plural) of the surface including the event point in association with the event point ID. Register to 112i.

  On the other hand, when the direct wave is shielded by the surface (S173), a unique propagation path ID is assigned to the propagation path of the direct wave, and the shielded surface ID of the invalid route data 113c in the route search data storage area 113 is assigned. The direct wave propagation path ID is registered in the corresponding invalid path ID registration column 113d, and necessary information is registered in the propagation path data storage area 112 (S175).

  Here, in the registration to the propagation path data storage area 112, first, a unique calculation point ID is assigned to the reception point input by the operator, and the calculation point ID and the coordinates of the reception point are registered in the calculation point list data 112a. To do. Then, calculation point data 112d related to the calculation point ID is generated, a direct wave propagation path ID is registered, and an identification code indicating “invalid” is registered.

  Next, the propagation path calculation unit 120 sets the number of reflections r to “1” (S176).

  Then, the propagation path calculation unit 120 searches for a propagation path having the number of reflections r by a so-called image method, and assigns a unique propagation path ID to each searched propagation path (S177).

  Among the propagation paths searched in step S177, those not yet checked whether or not they are shielded are extracted (S178), and it is calculated whether or not the extracted propagation paths are shielded by a surface (S178). S179).

  If the extracted propagation path is not shielded (S179), the effective path data 113a in the path search data storage area 113 corresponds to the surface ID of the surface on which the radio wave is reflected, diffracted or transmitted in the extracted propagation path. The propagation path ID of the extracted propagation path is registered in the effective path ID registration field 113b, and necessary information is registered in the propagation path data storage area 112 (S180).

  Here, in the registration to the propagation path data storage area 112, first, the propagation path ID of the propagation path extracted in the calculation point data 112d related to the calculation point ID corresponding to the reception point input by the operator is registered, and “valid” "Is registered. Furthermore, a point on the surface where the propagation path is reflected, transmitted or transmitted is specified, and the event point is assigned a unique event point ID, and is registered in the propagation path data 112g in association with the propagation path ID. In association with the event point ID, the coordinates of the event point, the identification code indicating reflection or transmission, and the surface ID of the surface including the event point are registered in the event point data 112i.

  On the other hand, when the extracted propagation path is blocked (S179), the invalid path ID corresponding to the surface ID of the surface where the radio wave is shielded in the extracted propagation path in the invalid path data 113c of the path search data storage area 113. The propagation path ID of the extracted propagation path is registered in the registration field 113d, and necessary information is registered in the propagation path data storage area 112 (S181).

  Here, in the registration to the propagation path data storage area 112, first, the propagation path ID of the extracted propagation path is registered in the calculation point data 112d related to the reception point input by the operator, and identification indicating “invalid” is performed. Register the code.

  Then, when there is a propagation path that has not yet been checked for the presence or absence of shielding in the searched propagation path (S182), the propagation path calculation unit 120 repeats the processing from step S178 to step S181 to search for the found propagation path. If there is no propagation path that has not been checked for shielding (S182), it is determined whether the number of reflections r is equal to or greater than the maximum number of reflections R (S183).

  If the number of reflections r is not equal to or greater than the maximum number of reflections R (S183), “1” is incremented to r (S184), and the processing from step S177 to step S183 is repeated.

  When the number of reflections r is equal to or greater than the maximum number of reflections R (S183), the calculation point data 112d stored in the propagation path data storage area 112 corresponds to the propagation path ID determined to be valid. The physical quantity of the radio wave passing through the propagation path is calculated by the physical quantity calculation unit 130 and stored in the calculation data storage area 114 (S185), and the process ends.

  Note that the propagation path and physical quantity calculated as described above are displayed on the display unit 160 as display data in a predetermined display format in the display processing unit 140.

  FIG. 12 is a flowchart showing a process for recalculating a physical quantity when a surface is changed.

  First, when the plane P is changed by the operator via the display unit 160 and the input unit 150 (S200), the propagation path calculation unit 120 determines whether the change of the plane P is a deletion (S201). If the change of the surface P is not deletion (S201), the information of the changed surface P ′ is registered in the model data storage area 111 (S202).

  Here, in the present embodiment, the change of the surface is assumed to be the change of the coordinates of the surface (shape deformation, parallel movement, rotation, reduction, enlargement, etc.) and the deletion of the surface.

  In addition, the registration of the changed surface P ′ information in the model data storage area 111 is performed by assigning a surface ID to the changed surface P ′ and registering it in the surface ID registration field 111b of the surface data 111a. The shape ID is assigned to the shape of P ′ and registered in the shape ID registration column 111c, and the physical property ID of the surface P before change is acquired and registered in the physical property ID registration column 111d. Then, for the shape specified by the shape ID, the coordinates of the vertex and the coordinates of the other vertex to which the vertex is connected are registered in the shape data 111e. Changes other than the deletion of the surface can be specified by specifying the coordinates of the vertex of the surface.

  For example, as shown in FIG. 16 (schematic diagram of display data for displaying a propagation path), the operator of the radio wave propagation characteristic calculation apparatus 100 inputs the input unit 150 and the display unit. It can be accepted by specifying the surface to be changed via 160 and changing its position and shape.

  Next, the propagation path calculation unit 120 extracts the effective path data 113a of the plane P from the path search data storage area 113, and specifies the propagation path registered in the effective path ID registration column 113b of the plane P (S203). .

  Then, out of the identified propagation paths, the propagation paths that have not been rechecked are extracted, the propagation paths are recalculated (S204), and whether or not the recalculated propagation paths are valid is determined. Determination is made (S205).

  Here, whether or not the propagation path is valid indicates that when the plane P is deleted, only the other planes are received from the transmission point without passing through the deleted plane P among the planes passing through the propagation path. If the surface P is changed to the surface P ′, even if the surface P is changed to the surface P ′ among the surfaces passing through the propagation path, the transmission point is determined. Judgment is made based on whether or not radio waves reach the receiving point from

  If it is determined that the recalculated propagation path is valid (S205), a unique propagation path ID is assigned to the recalculated propagation path, and this propagation path ID is sent to the physical quantity calculation unit 130. Necessary information is registered in the propagation path data storage area 112 (S206).

  Here, the registration to the propagation path data storage area 112 is performed by registering the propagation path ID of the recalculated propagation path in the calculation point data 112d related to the calculation point ID corresponding to the reception point and identifying “valid”. Register the code. Furthermore, a point on the surface where the propagation path is reflected, transmitted or transmitted is specified, and the event point is assigned a unique event point ID, and is registered in the propagation path data 112g in association with the propagation path ID. In association with the event point ID, the coordinates of the event point, the identification code indicating reflection or transmission, and the surface ID of the surface including the event point are registered in the event point data 112i.

  If there is a propagation path that has not been rechecked yet (S207), the processing from step S204 to step S207 is repeated.

  On the other hand, when there is no propagation path that has not been rechecked (S207), the propagation path calculation unit 120 extracts the invalid path data 113c of the plane P from the path search data storage area 113, and the plane P The propagation path registered in the invalid path ID registration field 113d is specified (S208).

  Then, out of the identified propagation paths, the propagation paths that have not been rechecked are extracted, the propagation paths are recalculated (S209), and whether or not the recalculated propagation paths are valid is determined. Verification is performed (S210).

  Here, whether or not the propagation path is valid depends on whether the propagation path shielded by the plane P deletes the plane P or changes the plane P to the plane P ′, so that the radio wave reaches the reception point from the transmission point. Judgment is made based on whether or not

  If it is determined that the recalculated propagation path is valid (S210), a unique propagation path ID is assigned to the recalculated propagation path, and this propagation path ID is sent to the physical quantity calculation unit 130. Necessary information is registered in the propagation path data storage area 112 (S211).

  Here, the registration to the propagation path data storage area 112 is performed by registering the propagation path ID of the recalculated propagation path in the calculation point data 112d related to the calculation point ID corresponding to the reception point and identifying “valid”. Register the code. Furthermore, a point on the surface where the propagation path is reflected, transmitted or transmitted is specified, and the event point is assigned a unique event point ID, and is registered in the propagation path data 112g in association with the propagation path ID. In association with the event point ID, the coordinates of the event point, the identification code indicating reflection or transmission, and the surface ID of the surface including the event point are registered in the event point data 112i.

  If there is a propagation path that has not been rechecked yet (S212), the processing from step S209 to step S212 is repeated.

  On the other hand, if there is no propagation path that has not been rechecked (S212), the physical quantity calculation unit 130 recalculates the physical quantity of the radio wave that has passed through the propagation path corresponding to the transmitted propagation path ID. Then, it is registered in the calculation data storage area 114 (S213), and the process ends.

  In the embodiment described above, the radio wave obstacle is specified by the surface. However, the present invention is not limited to this mode. For example, the radio wave obstacle is a three-dimensional object, and the surface constituting the object is implemented in this embodiment. Even when the shape is specified in the same manner as the form and the shape is changed, the physical quantity can be easily recalculated as in the present embodiment.

  In this embodiment, the attenuation is calculated as the physical quantity of the radio wave. However, the present invention is not limited to such a mode, and for example, the reception power, the electric field strength, the delay distribution, or the phase transition at the reception point is calculated. Is also possible.

1 is a schematic diagram of a radio wave propagation characteristic calculation apparatus 100. FIG. Schematic of the surface data 111a. Schematic of shape data 111e. Schematic of the physical property data 111h. Schematic of calculation point list data 112a. Schematic diagram of calculation point data 112d. Schematic of propagation path data 112g. Schematic of event point data 112i. Schematic of the effective route data 113a. Schematic of invalid route data 113c. The flowchart which shows the process which calculates the physical quantity of an electromagnetic wave. The flowchart which shows the process which recalculates the physical quantity at the time of changing a surface. Schematic of the display data which displays a propagation path. The schematic of the display data which displays electric field strength and phase distribution. Schematic of the display data which displays delay distribution. Schematic of the display data which displays a propagation path.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Radio wave propagation characteristic calculation apparatus 110 Storage part 111 Model data storage area 112 Propagation path data storage area 113 Path search data storage area 114 Calculation data storage area 120 Propagation path calculation part 130 Physical quantity calculation part 140 Display processing part 150 Input part 160 Display part

Claims (7)

A storage unit for storing a transmission point of the radio wave, a reception point of the radio wave, a shape of the obstructing surface, a position of the surface, and physical properties of the surface;
A radio wave propagation characteristic calculation device comprising: a plurality of propagation paths from the transmission point to the reception point; and a calculation unit that calculates a physical quantity of radio waves passing through the propagation path for each propagation path,
The storage unit stores search information for identifying the propagation path involved for each surface involved in the propagation path,
The computing unit is
When the surface is changed, a process of extracting the propagation path involving the changed surface from the search information;
A process of recalculating a propagation path through which radio waves reach from the transmission point to the reception point via the extracted planes involved in the propagation path;
A process of calculating a physical quantity of radio waves passing through the recalculated propagation path;
1. A radio wave propagation characteristic calculating apparatus characterized by: The radio wave propagation characteristic calculating apparatus according to claim 1,
The radio wave propagation characteristic calculation apparatus, wherein the calculation unit performs a process of calculating a physical quantity of the radio wave when it is determined that the recalculated propagation path is not shielded by the surface. The radio wave propagation characteristic calculating apparatus according to claim 1,
The radio wave propagation characteristic calculation apparatus according to claim 1, wherein the change of the surface is a change of the shape of the surface, a change of the position of the surface, or a deletion of the surface. Computer
Storage means for storing a transmission point of the radio wave, a reception point of the radio wave, the shape of the obstructing surface, the position of the surface, and the physical properties of the surface;
Calculating means for calculating a plurality of propagation paths from the transmission point to the reception point, and for each propagation path, calculating a physical quantity of radio waves passing through the propagation path;
A program that functions as
The storage means stores search information for specifying the propagation path involved for each surface involved in the propagation path,
The calculation means includes
When the surface is changed, a process of extracting the propagation path involving the changed surface from the search information;
A process of recalculating a propagation path through which radio waves reach from the transmission point to the reception point via the extracted planes involved in the propagation path;
A process of calculating a physical quantity of radio waves passing through the recalculated propagation path;
A program characterized by having The program according to claim 4,
A program for causing the calculation means to perform a process of calculating a physical quantity of the radio wave when it is determined that the recalculated propagation path is not shielded by the surface. The program according to claim 4,
The change of the surface is a change of the shape of the surface, a change of the position of the surface, or a deletion of the surface. A storage unit for storing a transmission point of the radio wave, a reception point of the radio wave, a shape of the obstructing surface, a position of the surface, and physical properties of the surface;
A radio wave propagation characteristic performed by a radio wave propagation characteristic calculation device comprising: a plurality of propagation paths from the transmission point to the reception point; and a calculation unit that calculates a physical quantity of the radio wave passing through the propagation path for each propagation path. A calculation method,
A process in which the storage unit stores search information for identifying the propagation path involved for each surface involved in the propagation path;
The calculation unit, when the surface is changed, a process of extracting the propagation path involving the changed surface from the search information;
A process in which the arithmetic unit recalculates a propagation path through which radio waves reach from the transmission point to the reception point via the extracted planes involved in the propagation path;
A process of calculating a physical quantity of radio waves passing through the recalculated propagation path by the arithmetic unit;
A radio wave propagation characteristic calculation method characterized by comprising:

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