Radio environment estimation system and radio environment estimation method

Abstract

To estimate a communication environment in a short time.SOLUTION: Holding stationary structure data including structure data of a stationary structure in a wireless communication area, mobile object data including structure data of a mobile object in the wireless communication area, and observation-area data related to an observation area of an electromagnetic field, and generating a first electromagnetic field analysis model for analyzing an electromagnetic wave reflected by the stationary structure in the observation area by using the stationary structure data and the observation-area data; Setting a primary wave source at a position of a radio station, generating a secondary transmission point from an electromagnetic field which is obtained by calculation using the first electromagnetic field analysis model and reaches the observation area, generating a second electromagnetic field analysis model for analyzing an electromagnetic wave radiated from the secondary transmission point using the mobile object data and the observation area data, and calculating an electromagnetic field by an electromagnetic wave radiated in a direction opposite to the electromagnetic wave reaching the secondary transmission point using the second electromagnetic field analysis model.SELECTED DRAWING: Figure 1a

Description

[Technical Field]

[0001] The present invention relates to a radio environment estimation system, and more particularly to a technology for estimating a radio environment within a wireless communication service area in order to realize a wireless digital twin that reproduces the radio environment within the service area. [Background technology]

[0002] Wireless systems are used to communicate information with remote targets, and also to monitor and control those targets, by transmitting and receiving information using electromagnetic waves. Electromagnetic waves, which are the communication medium, are emitted into space from a transmitter and then reach a receiver either directly or after being reflected and diffracted by electromagnetic wave scatterers. For this reason, the communication quality of wireless communications using electromagnetic waves is affected by the positions and attitudes of the scatterers surrounding the transmitter and receiver. Changes in the relative position and attitude of the electromagnetic wave scatterers due to movement change the wireless communication characteristics.

[0003] When electromagnetic wave scatterers are present around a transmitter or receiver, the electromagnetic field distribution can be analytically or numerically calculated by electromagnetic field analysis using Maxwell's equations, with the transmitter as the transmitting point, the receiver as the receiving point, and the electromagnetic wave scatterers as objects with permittivity and permeability. Generally, the difficulty, i.e., the calculation time, of electromagnetic field analysis increases exponentially with the increase in the number and complexity of the shapes of the electromagnetic wave scatterers around the transmitter or receiver. However, due to the rapid advancement of computer resources in recent years, in most wireless systems currently in operation, the calculation of the electromagnetic field distribution within the wireless system can now be performed in less than a minute.

[0004] In light of this situation, a technology called wireless digital twin has been proposed that uses electromagnetic field distribution obtained through electromagnetic field analysis using computer resources to reproduce in cyberspace the behavior of wireless systems existing in real space and estimate the communication characteristics of wireless systems in real space. Using data on the positions of transmitters and receivers within a wireless communication area and the positions, postures, structures, and electrical characteristics of electromagnetic wave scatterers around the transmitters and receivers, the electromagnetic field distribution at any location within a wireless communication service area can be calculated without actual measurements, and the wireless communication characteristics within that area can be reproduced in cyberspace using the calculation results. Using wireless digital twin, it is possible to predict wireless communication characteristics after changes in the position and posture of electromagnetic wave scatterers in real space.

[0005] The following prior art exists as background art in this technical field: Patent Document 1 (JP 2021-158397 A) describes a control device that includes a position prediction unit that predicts the position of a terminal having a communication function, an information acquisition unit that acquires geographic information around the position of the terminal predicted by the position prediction unit, and a communication control unit that controls communication between the terminal and other terminals other than the terminal that have the communication function based on the geographic information.

[0006] Furthermore, Patent Document 2 (JP 2023-39929 A) describes a method executed by an on-board computer of an ego vehicle, the method including: sensing a remote vehicle using a set of sensors of the ego vehicle to generate sensor data describing the driving behavior of the remote vehicle; comparing the sensor data to a set of criteria for abnormal driving behavior; determining that a subset of the set of criteria is described by the sensor data, wherein the subset satisfies a threshold for early detection of abnormal driving behavior; and determining that the remote vehicle is engaged in abnormal driving behavior based on the satisfaction of the threshold. [Prior art documents] [Patent documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2021-158397 [Patent Document 2] Japanese Patent Application Publication No. 2023-39929 Summary of the Invention [Problem to be solved by the invention]

[0008] The aforementioned prior art discloses techniques for monitoring and controlling the operating status of a mobile object. However, each technique assumes that the wireless communication line used to transmit monitoring and control information to the mobile object is high-quality and stable, and does not take into account the fluctuations in the wireless line required for monitoring and controlling the mobile object. When a mobile object is present within a wireless communication area, the wireless communication characteristics in real space generally change depending on the moving speed of the mobile object. If electromagnetic field analysis of the position and posture of a fixed electromagnetic wave scatterer requires several seconds to several minutes, a delay occurs in the position and posture of the mobile object due to the time required for the electromagnetic field analysis, and changes in the position and posture of the mobile object are not reflected in the wireless digital twin. When a wireless digital twin is used to evaluate the impact of a mobile object in a wireless system on the wireless communication environment and to monitor and control the mobile object itself, it is necessary to speed up electromagnetic field calculations according to the moving speed of the mobile object and generate a wireless digital twin at the most recent time. [Means for solving the problem]

[0009] A representative example of the invention disclosed in the present application is as follows: That is, a radio environment estimation system is configured by a computer having an arithmetic unit that executes predetermined processing and a storage device connected to the arithmetic unit, the storage device holds stationary structure data including structural data of stationary structures within a wireless communication area, mobile body data including structural data of mobile bodies within the wireless communication area, and observation area data regarding an observation area of ​​an electromagnetic field, the arithmetic unit uses the stationary structure data and the observation area data to generate a first electromagnetic field analysis model for analyzing electromagnetic waves reflected by stationary structures within the observation area, sets a primary wave source at the position of a wireless station, generates secondary transmission points from the electromagnetic field obtained by calculation using the first electromagnetic field analysis model and reaching the observation area, uses the mobile body data and the observation area data to generate a second electromagnetic field analysis model for analyzing electromagnetic waves radiated from the secondary transmission points, and uses the second electromagnetic field analysis model to calculate an electromagnetic field due to electromagnetic waves radiated in a direction opposite to the electromagnetic waves reaching the secondary transmission points. [Effects of the Invention]

[0010] According to one aspect of the present invention, it is possible to estimate the communication environment in a short time. Problems, configurations, and effects other than those described above will become apparent from the following description of the embodiments. [Brief explanation of the drawings]

[0011] [Figure 1a] FIG. 1 is a diagram illustrating a wireless digital twin according to a first embodiment. [Figure 1b] FIG. 2 is a diagram illustrating the operation of the radio environment estimation system according to the first embodiment. [Figure 1c] FIG. 2 is a diagram illustrating the operation of the radio environment estimation system according to the first embodiment. [Figure 1d] FIG. 2 is a diagram illustrating the operation of the radio environment estimation system according to the first embodiment. [Figure 1e] FIG. 2 is a diagram illustrating the operation of the radio environment estimation system according to the first embodiment. [Figure 1f] FIG. 2 is a diagram illustrating the operation of the radio environment estimation system according to the first embodiment. [Figure 1g] FIG. 10 is a diagram illustrating an example of the configuration of received segment accumulated data in the first embodiment. [Figure 1h] FIG. 10 is a diagram illustrating an example of the configuration of ray payload data according to the first embodiment. [Figure 1i] 3 is a flowchart of a process executed by the radio environment estimating system according to the first embodiment. [Figure 1j] FIG. 1 is a diagram illustrating a hardware configuration of a wireless environment estimation system according to a first embodiment. [Figure 2a] FIG. 10 is a diagram illustrating a wireless digital twin according to a second embodiment. [Figure 2b] FIG. 10 is a diagram illustrating a wireless digital twin according to a second embodiment. [Figure 2c] FIG. 10 is a diagram illustrating the operation of the radio environment estimation system according to the second embodiment. [Figure 2d] FIG. 10 is a diagram illustrating the operation of the radio environment estimation system according to the second embodiment. [Figure 2e] FIG. 10 is a diagram illustrating the operation of the radio environment estimation system according to the second embodiment. [Figure 2f] FIG. 10 is a diagram illustrating the operation of the radio environment estimation system according to the second embodiment. [Figure 3a] FIG. 10 is a diagram illustrating a wireless digital twin according to a third embodiment. [Figure 3b] FIG. 10 is a diagram illustrating a wireless digital twin according to a third embodiment. [Figure 3c] FIG. 10 is a diagram illustrating the operation of the radio environment estimation system according to the third embodiment. [Figure 3d] FIG. 10 is a diagram illustrating the operation of the radio environment estimation system according to the third embodiment. [Figure 3e] FIG. 10 is a diagram illustrating the operation of the radio environment estimation system according to the third embodiment. [Figure 3f] FIG. 10 is a diagram illustrating the operation of the radio environment estimation system according to the third embodiment. [Figure 4a] FIG. 10 is a diagram illustrating a wireless digital twin according to a fourth embodiment. [Figure 4b] FIG. 10 is a diagram illustrating the operation of the wireless environment estimation system according to the fourth embodiment. [Figure 4c]FIG. 10 is a diagram illustrating the operation of the wireless environment estimation system according to the fourth embodiment. [Figure 5a] FIG. 10 is a diagram illustrating a wireless digital twin of a fifth embodiment. [Figure 5b] FIG. 10 is a diagram illustrating a wireless digital twin of a fifth embodiment. [Figure 5c] FIG. 10 is a diagram illustrating a wireless digital twin of a fifth embodiment. [Figure 5d] FIG. 10 is a diagram illustrating a wireless digital twin of a fifth embodiment. [Figure 6] FIG. 13 is a diagram illustrating a wireless digital twin of a sixth embodiment. [Figure 7a] FIG. 13 is a diagram illustrating a configuration of a wireless environment estimation system according to a seventh embodiment. [Figure 7b] 13 is a flowchart of a process executed by a radio environment estimating system according to a seventh embodiment. [Figure 7c] 13 is a flowchart of a process executed by a radio environment estimating system according to a seventh embodiment. [Figure 8a] FIG. 13 is a diagram illustrating another configuration of the wireless environment measuring system according to the eighth embodiment. [Figure 8b] 13 is a flowchart of a process executed by a radio environment estimating system according to an eighth embodiment. [Figure 8c] 13 is a flowchart of a process executed by a radio environment estimating system according to an eighth embodiment. [Figure 9a] FIG. 13 is a diagram showing an example of display of the predicted results of the electromagnetic field distribution in Example 9. [Figure 9b] FIG. 13 is a diagram showing another example of display of the predicted results of the electromagnetic field distribution in Example 9. [Figure 10a] FIG. 19 is a diagram illustrating a configuration example of an operation monitoring and control system using a wireless digital twin according to a tenth embodiment. [Figure 10b] FIG. 20 is a diagram showing the current estimated wireless communication quality state of the wireless system as understood by the mobile control server of the tenth embodiment. [Figure 10c] FIG. 20 is a diagram showing the future predicted state of wireless communication quality of the wireless system predicted by the mobile control server of the tenth embodiment. [Figure 11]FIG. 23 is a diagram illustrating another example of the configuration of the operation monitoring and control system using the wireless digital twin of the eleventh embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment will be described with reference to the drawings. Example 1 A first embodiment of the present invention will be described with reference to FIGS. 1a to 1j.

[0013] FIG. 1a is a diagram illustrating a wireless digital twin of Example 1.

[0014] The wireless digital twin of Example 1 has multiple stationary structures 1, mobile objects 2, roads 3, a measurement plane 4, a base station 5, and multiple terminal stations 6 installed within the service area of ​​a wireless system 101. The measurement plane 4 is set above the road 3 at a height equal to or lower than the mobile objects 2 (for example, on the surface of the road 3), encompassing an area through which the mobile objects 2 may pass on the road 3. The base station 5 emits electromagnetic waves into space to communicate wirelessly with terminal stations 6 located at multiple points within the service area.

[0015] The emitted electromagnetic waves propagate in all directions in three-dimensional space as rays 11 that have the same properties as light, a type of electromagnetic wave. Of the multiple rays 11 emitted from base station 5, some reach terminal station 6 directly, while others are scattered by stationary structure 1 and reach terminal station 6 indirectly as reflected and diffracted waves, but most do not reach terminal station 6 and continue on toward infinity.

[0016] Because the measurement surface 4 is located near the moving object 2, the ray 11 that reaches the moving object 2 will always reach the measurement surface 4 if the moving object 2 is not present. If it is possible to observe the intensity, direction, and polarization of the ray 11 that reaches the measurement surface 4, in other words, if these states can be stored, it is possible to identify the ray 11 that reaches the moving object 2 by tracing the ray 11 backward from the measurement surface 4. Of the multiple rays 11 emitted from the base station 5, some are scattered by the stationary structure 1 and some are scattered by the moving object 2, so the ray 11 that is not scattered by the moving object 2 can be calculated in a virtual environment consisting of only the stationary structure 1 and the measurement surface 4, where the moving object 2 does not exist.

[0017] Furthermore, the ray 11 scattered from the moving body 2 can be generated from the ray 11 represented by information on the intensity, direction, and polarization that reach the measurement surface 4, which is obtained from the calculation results of the electromagnetic field in the virtual environment described above. Generally, the size of the stationary structure 1 present in the wireless system 101 is orders of magnitude larger than that of the moving body 2. Furthermore, because electromagnetic waves are waves, the interference between two rays 11 at locations more than half a wavelength apart is extremely small. Therefore, in order to maintain the accuracy of the electromagnetic field calculation using the ray 11, it is necessary to represent the surfaces of the stationary structure 1 and the moving body 2 by dividing them into dimensions of about half a wavelength. For this reason, the calculation amount for the interaction between the stationary structure 1 and the ray 11 is orders of magnitude larger than the calculation amount for the interaction between the moving body 2 and the ray 11. Reducing the calculation of the interaction between the ray 11 and the stationary structure 1 has a significant effect on reducing the calculation time for the electromagnetic field calculation using the ray 11.

[0018] In this embodiment, as shown in Figure 1b, in cyberspace where a stationary structure 1 and a moving body 2 coexist, the surface of the stationary structure 1 is divided into infinitesimal segments 12 each about half the wavelength in size, the surface of the moving body 2 is divided into infinitesimal segments 13 each about half the wavelength in size, the measurement surface 4 is composed of infinitesimal segments 14 each about half the wavelength in size, and the base station 5 is the transmission point 19 that radiates rays 11 in all directions in space.

[0019] Next, as shown in Figure 1c, an area where a moving object 2 may exist is identified in advance, and a measurement surface 4 is set up in the identified area. A stationary structure 1 whose surface is divided into infinitesimal segments 12 each about half the wavelength in size, and measurement surface 4 consisting of infinitesimal segments 14 each about half the wavelength are formed in cyberspace. Electromagnetic field analysis is performed by emitting a large number of rays 11 in all directions in space using base station 5 as the transmission point 19, and rays 11 representing the electromagnetic field on measurement surface 4 by information on intensity, direction, and polarization are stored, as shown in Figure 1d.

[0020] Next, as shown in Figure 1e, a moving object 2 whose surface is divided into infinitesimal segments 13 about half the size of a wavelength is formed in cyberspace, and multiple rays 21 that trace back the ray 11 incident on the measurement surface 4 are emitted from each infinitesimal segment 14 on the measurement surface 4 as secondary transmission points, and electromagnetic field analysis is performed to calculate the electromagnetic field distribution over the entire area within the service area of ​​the wireless system 101. In this case, as shown in Figure 1f, in calculating the interaction between the infinitesimal segments 13 that represent the moving object 2 and the rays 21, it is important to note that the ray 21 emitted from the measurement surface 4 traces back the ray 11 that was incident on the measurement surface 4, and therefore the law of refraction is reversed so that the original ray 11 matches the scattering phenomenon that occurs on the infinitesimal segments 13 that represent the moving object 2.

[0021] 1g and 1h show examples of the data configuration of the measurement surface 4 and attributes given to the rays 11 and 21 required for ray tracing calculation, which is an example of the electromagnetic field calculation of this embodiment.

[0022] As shown in Figure 1g, multiple rays 11 and 21 arrive at the measurement plane 4. For each infinitesimal segment 14 constituting the measurement plane 4, the system stores IDs for identifying the arriving rays 11 and 21, as well as the signal strength, polarization vector, angle of incidence with respect to the infinitesimal segment 14, path length to the segment, and number of scattering events for the rays 11 and 21 corresponding to each ID. The path length and number of scattering events are used to discard rays 11 and 21 whose signal strength has decreased to the point where communication quality cannot be maintained in ray tracing calculations. Furthermore, as shown in Figure 1h, each ray 11 and 21 emitted from the transmission point 19 is assigned a payload for storing the propagation vector representing the direction of travel, horizontal polarization intensity, vertical polarization intensity, cumulative path length, and number of scattering events. This payload information is necessary for calculations at the measurement plane 4.

[0023] 1i shows the procedure of the process executed by the radio environment estimation system 50 of this embodiment. First, three-dimensional structural data of the stationary structure 1 is acquired (S101), and a measurement plane 4 is set above the road 3 at a height equal to or lower than the height of the moving object 2, encompassing an area through which the moving object 2 may pass on the road 3 (S102).

[0024] Then, a calculation model required for electromagnetic field analysis is generated from the structural data of the stationary structure 1 and the information on the measurement surface 4 (S103), a transmission point 19 that emits rays 11 in all directions in space is set at the position of the base station 5 (S104), rays 11 are emitted using the set transmission point 19 as the radiation source (S105), and electromagnetic field calculation is performed using the ray tracing method (S106).

[0025] Furthermore, from the information of the rays 11 that have reached each infinitesimal segment 14 on the measurement surface 4, derived by the electromagnetic field calculation, secondary transmission points are generated that radiate multiple rays 21 that trace back the arrived rays 11 from each infinitesimal segment 14 on the measurement surface 4 (S107). Then, structural data of the stationary structure 1 is acquired, and the measurement surface 4 is reset to the stationary structure 1 (S108), 3D data (snapshot) of the position of the moving body 2 at a specific time point is acquired (S109), a calculation model required for electromagnetic field analysis is generated from the structural data of the moving body 2 and the information of the measurement surface 4 (S110), rays 21 are radiated in a specific direction in space using the generated secondary transmission points as radiation sources (S111), and electromagnetic field calculation is performed using the ray tracing method (S112).

[0026] Then, the electromagnetic field estimation result calculated in step S106 and the electromagnetic field estimation result calculated in step S112 are summed to derive the overall electromagnetic field in the environment of the service area of ​​the wireless system 101.

[0027] 1i is configured by a computer having a processor (CPU) 501, a memory 502, an auxiliary storage device 503, and a communication interface 504, as shown in Fig. 1j. The radio environment estimation system 50 may also have an input interface 505 and an output interface 508.

[0028] The processor 501 is an arithmetic device that executes programs stored in the memory 502. The processor 501 executes various programs to realize the functions of the functional units of the radio environment estimation system 50. Note that some of the processing performed by the processor 501 by executing the programs may be executed by another arithmetic device (for example, hardware such as an ASIC or FPGA).

[0029] The memory 502 includes a ROM, which is a non-volatile storage element, and a RAM, which is a volatile storage element. The ROM stores unchanging programs (e.g., BIOS) and the like. The RAM is a high-speed, volatile storage element such as a DRAM (Dynamic Random Access Memory), and temporarily stores programs executed by the processor 501 and data used when the programs are executed.

[0030] The auxiliary storage device 503 is, for example, a large-capacity non-volatile storage device such as a magnetic storage device (HDD) or a flash memory (SSD). The auxiliary storage device 503 also stores data used by the processor 501 when executing a program, and the program executed by the processor 501. That is, the program is read from the auxiliary storage device 503, loaded into the memory 502, and executed by the processor 501 to realize each function of the radio environment estimation system 50.

[0031] The communication interface 504 is a network interface device that controls communication with other devices according to a predetermined protocol.

[0032] The input interface 505 is an interface to which input devices such as a keyboard 506 and a mouse 507 are connected and which receives input from an operator. The output interface 508 is an interface to which output devices such as a display device 509 and a printer (not shown) are connected and which outputs the results of program execution in a format that can be viewed by the user. Note that a user terminal connected to the radio environment estimation system 50 via a network may provide the input device and the output device. In this case, the radio environment estimation system 50 may have a web server function, and the user terminal may access the radio environment estimation system 50 using a predetermined protocol (for example, http).

[0033] The programs executed by the processor 501 are provided to the radio environment estimation system 50 from removable media (such as a CD-ROM or flash memory) or via a network, and are stored in a non-volatile auxiliary storage device 503, which is a non-transitory storage medium. For this reason, the radio environment estimation system 50 may have an interface for reading data from removable media.

[0034] The radio environment estimation system 50 is a computer system configured on one physical computer or on multiple logically or physically configured computers, and may run on a virtual computer built on multiple physical computer resources. For example, multiple programs that realize the functions of the radio environment estimation system 50 may each run on a separate physical or logical computer, or multiple programs may be combined and run on a single physical or logical computer.

[0035] In this embodiment, the number of rays 11 formed on the moving body 2 and the measurement surface 4 in the electromagnetic field calculation and the number of infinitesimal segments 14 used in the calculation are extremely small compared to the number of rays 11 formed on the stationary structure 1 and the measurement surface 4 in the electromagnetic field calculation and the number of infinitesimal segments 12 used in the calculation, thereby shortening the time required for the electromagnetic field calculation for the rays 21 formed on the moving body 2 and the measurement surface 4. This allows the future communication environment to be estimated in a short time, ensuring communication reliability while reducing the consumption of communication resources. Furthermore, a wireless digital twin can be realized that reproduces changes in the radio wave environment within the service area of ​​the wireless system 101 due to changes in the moving body 2, making it possible to estimate changes in the radio wave environment caused by the moving body 2, and improving the stability and reliability of wireless remote control of devices within the same area using the estimated results of the electromagnetic environment at a future time.

[0036] <Example 2> A second embodiment of the present invention will be described with reference to Figures 2a to 2f. In the second embodiment, differences from the first embodiment will be mainly described, and the same configurations and processes as those in the first embodiment will be assigned the same reference numerals, and descriptions thereof will be omitted.

[0037] In the first embodiment, a moving object 2 and a measurement surface 4 are installed, which move in a plane within the service area of ​​the wireless system 102. However, in the second embodiment, a flying object 22 and a measurement closed surface 24 are installed, which move three-dimensionally within the space within the service area of ​​the wireless system 101. Figures 2a and 2b are diagrams showing the wireless digital twin of the second embodiment, with Figure 2b omitting the infinitesimal segments 16 that do not become secondary transmission points. Figures 2c and 2d are diagrams showing rays 31 emitted from the infinitesimal segments 16, with Figure 2d omitting the infinitesimal segments 16 that do not become secondary transmission points. Figures 2e and 2f are enlarged views of the measurement closed surface 24, with Figure 2f omitting the infinitesimal segments 16 that do not become secondary transmission points.

[0038] 2a and 2b, the measurement closed surface 24 encompasses a three-dimensional region in which a flying object 22 may exist, and is represented by a closed figure formed of a plurality of infinitesimal segments 16, which are surface elements. In the second embodiment, as in the first embodiment, electromagnetic field calculations are performed in cyberspace where only a stationary structure 1 exists and no flying object 22 exists, and information on the intensity, direction, and polarization of each infinitesimal segment 16 is stored for each ray 11 passing through the measurement closed surface 24. The rays 11 stored in each infinitesimal segment 16 are only rays radiated from the inside to the outside of the measurement closed surface 24.

[0039] Next, as shown in Figures 2c, 2d, 2e, and 2f, ray 31 is emitted based on the information on intensity, direction, and polarization stored in each infinitesimal segment 16. Ray 31 is a ray emitted from the inside to the outside of the measurement closed surface 24, and is emitted in the opposite direction to ray 11, and the same scattering calculation is performed as for ray 21 in Example 1. The calculation when ray 31 interacts with infinitesimal segment 15 that divides and represents the surface of flying object 22 is the same as the calculation when ray 21 in Example 1 interacts with infinitesimal segment 13 that divides and represents moving object 2.

[0040] According to this embodiment, it is effective in realizing a wireless digital twin that estimates wireless communication characteristics within a wireless communication area that includes an object moving three-dimensionally, in accordance with the movement of the moving object.

[0041] Example 3 A third embodiment of the present invention will be described with reference to Figures 3a to 3f. In the third embodiment, differences from the first embodiment will be mainly described, and the same configurations and processes as those in the first embodiment will be assigned the same reference numerals, and descriptions thereof will be omitted.

[0042] In the first embodiment, a moving object 2 and a measurement surface 4 are installed, which move in a plane within the service area of ​​the wireless system 103. However, in the third embodiment, a flying object 22 and a measurement shell 34 are installed, which move three-dimensionally within the space within the service area of ​​the wireless system 103. Figures 3a and 3b are diagrams showing the wireless digital twin of the second embodiment, with Figure 3b omitting the infinitesimal segments 16 that do not become secondary transmission points. Figures 3c and 3d are diagrams showing rays 31 emitted from the infinitesimal segments 16, with Figure 3d omitting the infinitesimal segments 16 that do not become secondary transmission points. Figures 3e and 3f are enlarged views of the measurement closed surface 24, with Figure 3f omitting the infinitesimal segments 16 that do not become secondary transmission points.

[0043] 3a and 3b, the measurement shell 34 encompasses a three-dimensional region in which the flying object 22 may exist, and is expressed as a closed shape formed by a plurality of minute voxels 44, which are three-dimensional elements. In the third embodiment, as in the first embodiment, electromagnetic field calculations are performed in cyberspace where only the stationary structure 1 exists and no flying object 22 exists, and information on the intensity, direction, and polarization of each minute voxel 44 is stored for each ray 11 passing through the measurement shell 34. The rays 11 stored in each minute voxel 44 are only rays emitted from the interior to the outside of the measurement shell 34.

[0044] Next, as shown in Figures 3c and 3d, ray 41 is emitted based on the intensity, direction, and polarization information stored in each micro voxel 44. Ray 41 is a ray emitted from the interior to the outside of the measurement shell 34, and is emitted in the opposite direction to ray 11. The same scattering calculation is performed as for ray 21 in Example 1. The calculation when ray 41 interacts with micro segments 15 that divide and represent the surface of the flying object 22 is the same as the calculation when ray 21 in Example 1 interacts with micro segments 13 that divide and represent the moving object 2. In Example 2, the calculation accuracy of the interaction between ray 11 incident in a direction close to perpendicular to the normal to micro segment 16 and the micro segment 16 deteriorates. In this example, ray 11 enters micro voxel 44. Therefore, when ray 11 enters from a direction close to perpendicular to the normal to one face of the micro voxel 44, ray 11 interacts with another face of the micro voxel 44. This suppresses deterioration in the calculation accuracy of the interaction of the micro voxel 44 as a whole.

[0045] According to this embodiment, it is possible to improve the accuracy of estimating wireless communication characteristics of a wireless digital twin that estimates wireless communication characteristics within a wireless communication area that includes an object moving three-dimensionally, in accordance with the movement of the moving body.

[0046] Example 4 A fourth embodiment of the present invention will be described with reference to Figures 4a to 4c. In the fourth embodiment, differences from the first embodiment will be mainly described, and the same configurations and processes as those in the first embodiment will be assigned the same reference numerals, and descriptions thereof will be omitted.

[0047] FIG. 4a is a diagram illustrating a wireless digital twin of Example 4.

[0048] The fourth embodiment differs from the first embodiment in that a LiDAR 7 is installed to measure the position and shape of an object within the service area, such as a moving object 2 traveling within the service area of ​​the wireless system 104.

[0049] The LiDAR 7 can observe the position and shape of the moving object 20 within the service area in time series, and can measure the moving speed and moving direction of the moving object 20 based on the observed position and shape. A method for estimating the electromagnetic field environment in the service area at a future time in cyberspace using the moving speed and moving direction of the moving object 20 acquired by the LiDAR 7 will be described with reference to FIGS. 4b and 4c. First, as shown in FIG. 4b, the radio environment estimation system 50 performs electromagnetic field calculations using structural data related to the stationary structure 1 and the measurement surface 4. Next, using the information related to the moving speed and moving direction of the moving object 2 acquired by the LiDAR 7, it calculates the position and attitude of the moving object 2 at a future time in cyberspace, and estimates the electromagnetic field distribution in the service area at a future time using the structural data related to the moving object 2 at the future time and multiple rays 21 radiated from the measurement surface that have already been derived by electromagnetic field calculations for the stationary structure 1 and the measurement surface 4.

[0050] According to this embodiment, the electromagnetic field distribution at a future time within the service area of ​​the wireless system 104 for the mobile object 2 can be estimated, and the quality of wireless communication within the same area at a future time can be predicted from the estimated electromagnetic field distribution, thereby improving the safety and stability of the operation of equipment controlled by wireless communication.

[0051] <Example 5> A fifth embodiment of the present invention will be described with reference to Figures 5a to 5d. In the fifth embodiment, differences from the first embodiment will be mainly described, and the same configurations and processes as those in the first embodiment will be assigned the same reference numerals, and descriptions thereof will be omitted.

[0052] 5a to 5d are diagrams illustrating a wireless digital twin of Example 5.

[0053] In the fifth embodiment, as in the fourth embodiment, the position and posture of a mobile object 2 within the service area of ​​the wireless system 105 are observed over time by the LiDAR 7, and the electromagnetic field distribution at each time is sequentially calculated. The difference between the electromagnetic field distributions obtained at each time is calculated, and the fluctuations in the electromagnetic field within the service area can be quantitatively grasped. For example, the mobile object 2 shown in FIG. 5a moves to the position shown in FIG. 5b after a predetermined time, and the electromagnetic field environment changes. Furthermore, the mobile object 2 shown in FIG. 5c moves to the position shown in FIG. 5d after a predetermined time, and the electromagnetic field environment changes. Since the magnitude of the fluctuations in the electromagnetic field has an inverse relationship with the stability of wireless communication quality, it is possible to know the dynamic changes in wireless communication quality within the service area, which is effective for designing the placement of terminal stations for stable operation of the wireless system 105.

[0054] Example 6 A sixth embodiment of the present invention will be described with reference to Fig. 6. In the sixth embodiment, differences from the fifth embodiment will be mainly described, and the same configurations and processes as those in the fifth embodiment will be assigned the same reference numerals, and descriptions thereof will be omitted.

[0055] FIG. 6 is a diagram illustrating a wireless digital twin of the sixth embodiment.

[0056] The sixth embodiment differs from the fifth embodiment in that a camera 8 is installed to measure the position and shape of an object within the service area, such as a moving object 2 traveling within the service area of ​​the wireless system 106.

[0057] The camera 8 can observe the position and shape of the moving object 2 present within the service area in time series, and the radio environment estimation system 50 can measure the moving speed and direction of the moving object 2 based on the observed position and shape. Using multiple image data acquired by the camera 8 at different times and from different locations, the relative position between the moving object 2 and the stationary structure 1, as well as the size, moving direction, and moving speed of the moving object 2, can be estimated. The estimated relative position, size, moving direction, and moving speed of the moving object 2 are then used to calculate the position and attitude of the moving object 2 at a future time in cyberspace. The electromagnetic field distribution within the service area at a future time is then estimated using structural data regarding the moving object 2 at the future time and multiple rays 21 radiated from the measurement surface 4 derived by electromagnetic field calculation regarding the stationary structure 1 and the measurement surface 4. In this way, the electromagnetic field environment within the service area at a future time can be estimated in cyberspace using the moving speed and moving direction of the moving object 2 acquired by the camera 8.

[0058] Since camera 8 has cheaper hardware than LiDAR, it is possible to reduce the cost of introducing a wireless digital twin that estimates wireless communication characteristics within a wireless communication area in accordance with the movement of the mobile object.

[0059] Example 7 A seventh embodiment of the present invention will be described with reference to Figures 7a to 7c. In the seventh embodiment, differences from the first embodiment will be mainly described, and the same configurations and processes as those in the first embodiment will be assigned the same reference numerals, and descriptions thereof will be omitted.

[0060] FIG. 7a is a diagram showing the configuration of a radio environment estimation system 50 according to a seventh embodiment.

[0061] The wireless environment estimation system 50 mainly comprises a calculation engine 300 that performs electromagnetic field calculations within the service area of ​​the wireless system 101, an electromagnetic field calculation control device 310 that supplies various data required by the calculation engine 300 and manages the calculation results performed by the calculation engine 300, a measurement area control device 320 that provides data required for calculations by the calculation engine 300, a point cloud analysis device 330 that provides data required for calculations by the calculation engine 300, a structure data generation device 340 that generates structure data, and an output control device 350 that externally outputs various trial results using the digital twin. Next, the operation of each component will be described in detail.

[0062] First, the electromagnetic field calculation control device 310 has a secondary transmission point generation device 311, a moving body polygon generation device 312, a structure polygon generation device 313, and a receiving polygon generation device 314. The receiving polygon generation device 314 determines the measurement surface 4 using data sent from the measurement area control device 320, generates receiving polygons that become infinitesimal segments 16 that form the determined measurement surface 4, and outputs them to the calculation engine 300. The structure polygon generation device 313 uses data sent from the structure data generation device 340 to generate receiving polygons that become infinitesimal segments 16 related to the stationary structure 1, and outputs them to the calculation engine 300. The moving body polygon generation device 312 uses data sent from the point cloud analysis device 330 to generate receiving polygons that become infinitesimal segments 13 related to the moving body 2, and outputs them to the calculation engine 300. The secondary transmission point generator 311 generates secondary transmission points using the results of the electromagnetic field calculation by the calculation engine 300 , and outputs the secondary transmission points to the calculation engine 300 .

[0063] Second, the measurement area control device 320 has a reception area generation device 321 and a transmission point generation device 322, and outputs data related to the reception surface and transmission point 19. The reception area generation device 321 acquires information related to the area for analyzing wireless communication quality in the wireless digital twin from the reception area input device 329, and outputs it to the reception area generation device 321. The transmission point generation device 322 acquires information related to the emission point of ray 11 in the electromagnetic field calculation from the base station position input device 328, and outputs it to the transmission point generation device 322.

[0064] Third, the point cloud analysis device 330 includes a surface correction device 331, a mobile object model data generation device 332, a point cloud / surface conversion device 333, and a point cloud storage device 334. The point cloud storage device 334 acquires the output of a point cloud data measurement device 339 that acquires structural data of mobile objects 2 within the service area of ​​the wireless system 101 as a point cloud, stores the acquired data, and outputs it to the point cloud / surface conversion device 333. The point cloud / surface conversion device 333 converts the point cloud into planar segments and outputs them to the surface correction device 331. The surface correction device 331 checks the connection status of the planar segments output from the point cloud / surface conversion device 333, corrects any deficiencies, and outputs information about the planar segments to the mobile object model data generation device 332. The mobile object model data generation device 332 outputs the information about the planar segments to the point cloud analysis device 330.

[0065] Fourth, the structural data generation device 340 includes a structural database 341, a surface correction device 342, a point cloud / surface conversion device 343, a point cloud storage device 344, and a model data generation device 345. The point cloud storage device 344 acquires structural data of stationary structures 1 within the service area of ​​the wireless system 101 as a point cloud from a point cloud data acquisition device 348, stores the acquired data, and outputs it to the point cloud / surface conversion device 343. The point cloud / surface conversion device 343 converts the input point cloud into planar segments and outputs them to the surface correction device 342. The surface correction device 342 checks the connection status of the planar segments output from the point cloud / surface conversion device 343, corrects any deficiencies, and outputs information about the planar segments to the structural database 341. Data regarding structures existing within the service area may be generated from a point cloud obtained by actual measurement, or may be output to the structural data generation device 340 by the structural data input device 349. The model data generating device 345 outputs the data relating to the structure output from the structural data input device 349 and the data relating to the structure read from the structural database 341 to the outside of the structural data generating device 340 .

[0066] Fifth, the output control device 350 has a field intensity data storage device 351, a structure / moving body data storage device 352, and a display data generation device 353. The field intensity data storage device 351 acquires the electromagnetic field analysis results from the calculation engine 300. The structure / moving body data storage device 352 acquires from the calculation engine 300 data related to the stationary structure 1 and the moving body 2 that the calculation engine 300 used in the electromagnetic field calculation. The display data generation device 353 generates image data representing the electromagnetic field intensity using the data acquired by the field intensity data storage device 351 and the data acquired by the structure / moving body data storage device 352, and outputs the image data to a display device 359.

[0067] 7b and 7c are flowcharts of the process in which the wireless environment estimation system 50 of the seventh embodiment generates a wireless digital twin.

[0068] First, the radio environment estimation system 50 acquires point cloud data of a stationary structure (S201), converts the acquired point cloud into a polygon (S201), generates infinitesimal segments with which rays related to the stationary structure interact from the polygon (S203), and reads data related to the receiving surface (S204).The radio environment estimation system 50 then generates a measurement surface from the data related to the receiving surface and generates infinitesimal segments on the measurement surface with which rays interact (S205), reads base station data (S206), and generates transmission points that radiate rays 11 in all directions in space from the read base station data (S207).

[0069] Then, the wireless environment estimation system 50 radiates rays 11 from the transmission point 19 (S208), performs electromagnetic field calculations within the service area of ​​the wireless system 101 using the radiated rays 11 (S209), determines the electromagnetic field distribution to be generated on the measurement surface 4 based on the results of the electromagnetic field calculations (S210), finds multiple transmission points 19 that secondarily radiate rays 21 from the infinitesimal segments 14 generated on the measurement surface 4 based on the determined electromagnetic field distribution (S211), and calculates the direction of travel, intensity, and polarization characteristics of the secondarily radiated rays 21 using the results of the electromagnetic field calculations on the measurement surface (S212).

[0070] Then, the radio environment estimation system 50 acquires point cloud data of the moving object 2 (S213), converts the acquired point cloud data into polygons (S214), and generates infinitesimal segments 13 with which rays 11 related to the moving object 2 interact from the converted polygons (S215).The radio environment estimation system 50 then reads data related to the receiving surface (S216), and generates infinitesimal segments 14 with which rays 11 interact on the measurement surface generated from the read data related to the receiving surface (S217).

[0071] Then, the wireless environment estimation system 50 emits rays 21 in specific directions from multiple secondary transmission points generated on the measurement surface (S218), performs electromagnetic field calculations within the service area of ​​the wireless system 101 using the emitted rays 21 (S219), determines the electromagnetic field distribution to be generated on the measurement surface 4 from the results of the electromagnetic field calculations (S220), generates data for displaying the determined electromagnetic field distribution (S221), and creates data for displaying structures consisting of stationary structures 1 and moving bodies 2 within the service area (S222).

[0072] Since the location and posture of the moving object 2 change from moment to moment within the service area of ​​the wireless system 101, the process returns to step S213 after the process of step S222.

[0073] According to this embodiment, the movement of a moving body 2 within a wireless communication area, including an object moving three-dimensionally, is detected using a point cloud measurement device such as LiDAR, and this is effective in realizing a wireless digital twin that estimates wireless communication characteristics according to the moment-to-moment state of the moving body 2.

[0074] Example 8 An eighth embodiment of the present invention will be described with reference to Figures 8a to 8c. In the eighth embodiment, differences from the seventh embodiment will be mainly described, and the same configurations and processes as those in the seventh embodiment will be assigned the same reference numerals, and descriptions thereof will be omitted.

[0075] FIG. 8a is a diagram showing another configuration of the wireless environment estimation system 50 according to the eighth embodiment.

[0076] The wireless environment estimation system 50 mainly comprises a calculation engine 300 that performs electromagnetic field calculations within the service area of ​​the wireless system 101, an electromagnetic field calculation control device 310 that supplies various data required by the calculation engine 300 and manages the calculation results performed by the calculation engine 300, a measurement area control device 320 that provides the calculation engine 300 with data required for calculations, an image analysis device 360 ​​that provides the calculation engine 300 with data required for calculations, a structure data generation device 340 that generates structure data, and an output control device 350 that externally outputs various trial results using the digital twin. Next, the operation of each component will be described in detail.

[0077] First, the electromagnetic field calculation control device 310 has a secondary transmission point generator 311, a moving body polygon generator 312, a structure polygon generator 313, and a receiving polygon generator 314. The receiving polygon generator 314 determines the measurement surface 4 using data sent from the measurement area control device 320, generates receiving polygons that become infinitesimal segments 16 that form the determined measurement surface 4, and outputs them to the calculation engine 300. The structure polygon generator 313 uses data sent from the structure data generator 340 to generate receiving polygons that become infinitesimal segments 16 related to the stationary structure 1, and outputs them to the calculation engine 300. The moving body polygon generator 312 uses data sent from the image analysis device 360 ​​to generate receiving polygons that become infinitesimal segments 13 related to the moving body 2, and outputs them to the calculation engine 300. The secondary transmission point generator 311 generates secondary transmission points using the results of the electromagnetic field calculation by the calculation engine 300 , and outputs the secondary transmission points to the calculation engine 300 .

[0078] Second, the measurement area control device 320 has a reception area generation device 321 and a transmission point generation device 322, and outputs data related to the reception surface and transmission point 19. The reception area generation device 321 acquires information related to the area for analyzing wireless communication quality in the wireless digital twin from the reception area input device 329, and outputs it to the reception area generation device 321. The transmission point generation device 322 acquires information related to the emission point of ray 11 in the electromagnetic field calculation from the base station position input device 328, and outputs it to the transmission point generation device 322.

[0079] Third, the video analysis device 360 ​​includes a structure database 361, a structure model database 362, a video assessment device 363, a model data generation device 364, and a video storage device 365. The video storage device 365 acquires the output of a video capture device 369 that captures structural data of moving objects 2 within the service area of ​​the wireless system 101 as video, stores the acquired data, and outputs it to the video assessment device 363. The structure database 361 stores in advance images of various moving objects 2 and images of stationary structures within the wireless service area. The structure model database 362 stores information in which the images of various moving objects 2 are associated with shape data. The video assessment device 363 uses the information stored in the video storage device 365 and the information held in the structure database 361 to determine the position, direction of movement, and speed of the moving object 2, and sends the determined position, direction of movement, and speed of the moving object 2 to the model data generation device 364. The model data generation device 364 uses the information stored in the structural model database 362 to generate planar segments that represent the moving body 2 in cyberspace, and outputs information about the generated planar segments to the outside of the video analysis device 360.

[0080] Fourth, the structural data generation device 340 includes a structural database 341, a surface correction device 342, a point cloud / surface conversion device 343, a point cloud storage device 344, and a model data generation device 345. The point cloud storage device 344 acquires structural data of stationary structures 1 within the service area of ​​the wireless system 101 as a point cloud from a point cloud data acquisition device 348, stores the acquired data, and outputs it to the point cloud / surface conversion device 343. The point cloud / surface conversion device 343 converts the input point cloud into planar segments and outputs them to the surface correction device 342. The surface correction device 342 checks the connection status of the planar segments output from the point cloud / surface conversion device 343, corrects any deficiencies, and outputs information about the planar segments to the structural database 341. Data regarding structures existing within the service area may be generated from a point cloud obtained by actual measurement, or may be output to the structural data generation device 340 by the structural data input device 349. The model data generating device 345 outputs the data relating to the structure output from the structural data input device 349 and the data relating to the structure read from the structural database 341 to the outside of the structural data generating device 340 .

[0081] Fifth, the output control device 350 has a field intensity data storage device 351, a structure / moving body data storage device 352, and a display data generation device 353. The field intensity data storage device 351 acquires the electromagnetic field analysis results from the calculation engine 300. The structure / moving body data storage device 352 acquires from the calculation engine 300 data related to the stationary structure 1 and the moving body 2 that the calculation engine 300 used in the electromagnetic field calculation. The display data generation device 353 generates image data representing the electromagnetic field intensity using the data acquired by the field intensity data storage device 351 and the data acquired by the structure / moving body data storage device 352, and outputs the image data to a display device 359.

[0082] 8b and 8c are flowcharts of the process in which the wireless environment estimation system 50 of the eighth embodiment generates a wireless digital twin.

[0083] Steps S201 to S212 are the same as those in the seventh embodiment (FIG. 7b). After step S212, the radio environment estimation system 50 acquires image data of the moving object 2 (S231), compares the acquired image with images of structures within the service area of ​​the radio system 101 that are stored in advance in the structure database 341 (S232), and identifies the position of the moving object 2 (S233). The radio environment estimation system 50 also compares the acquired image with images of various moving objects 2 that are stored in advance in the structure database 361 (S234), and identifies a shape associated with the type of moving object 2 (S235). Thereafter, the radio environment estimation system 50 generates, from the identified position and shape of the moving object 2, an infinitesimal segment 13 with which the ray 11 related to the moving object 2 interacts (S215). The subsequent steps S216 to S222 are the same as those in the seventh embodiment (FIG. 7c).

[0084] According to this embodiment, the movement of a moving body 2 within a wireless communication area, including an object moving three-dimensionally, is detected using an image capturing device such as a camera that is cheaper than a point cloud measurement device such as LiDAR, and this is effective in realizing a wireless digital twin that estimates the wireless communication characteristics according to the moment-to-moment state of the moving body 2.

[0085] Example 9 A ninth embodiment of the present invention will be described with reference to Figures 9a and 9b. In the ninth embodiment, differences from the first embodiment will be mainly described, and the same configurations and processes as those in the first embodiment will be assigned the same reference numerals, and descriptions thereof will be omitted.

[0086] Fig. 9a is a diagram showing a display example of the predicted results of the electromagnetic field distribution in Example 9, and shows a display example of the estimated and predicted results of the electromagnetic field distribution within the service area of ​​the wireless system 101 in the wireless digital twin by the wireless environment estimation system 50. Fig. 9b is a diagram showing a display example in which the infinitesimal segments 16 that do not become secondary transmission points are omitted.

[0087] The wireless digital twin of Example 9 can individually display the effects of the stationary structure 1 and the mobile object 2 on the electromagnetic field distribution within the service area. For example, as shown in the upper left of Figures 9a and 9b, the electromagnetic field distribution obtained by electromagnetic field analysis, i.e., the ray 11 emitted from the base station 5 and the ray 21 emitted from the infinitesimal segment 12, can be displayed. In particular, as shown in the lower part of Figures 9a and 9b, the fluctuations in the electromagnetic field distribution within the service area contributed by the mobile object 2 are displayed rapidly in response to changes in the position and attitude of the mobile object 2. The wireless digital twin of Example 9 stores data on the stationary structures within the service area in advance, and the structural data of the mobile object 2 can be acquired in real time using a LiDAR 7 and / or a camera 8. Therefore, as shown in the upper right of Figures 9a and 9b, this structural data can be displayed superimposed on the electromagnetic field distribution obtained by electromagnetic field analysis. By simultaneously displaying the actual state of the stationary structure 1 and the mobile object 2 in real space and the electromagnetic field that actually exists as energy in space, planning for the stable operation of the wireless system 101 and formulating responses to changes in the operating status can be accelerated and made more effective. This is particularly effective when a moving object 2, whose behavior is generally difficult to identify, hinders the formulation of plans for stable operation and responses to changes.

[0088] According to this embodiment, the observed position of the mobile body 2 is input into the wireless environment estimation system 50 and the digital twin, and the wireless communication quality within the control area of ​​the mobile body 2 is estimated, allowing the mobile body 2 to operate stably and safely.

[0089] Example 10 A tenth embodiment of the present invention will be described with reference to Figures 10a to 10c. In the tenth embodiment, differences from the first embodiment will be mainly described, and the same configurations and processes as those in the first embodiment will be assigned the same reference numerals, and descriptions thereof will be omitted.

[0090] FIG. 10a is a diagram illustrating an example of the configuration of an operation monitoring and control system using a wireless digital twin according to a tenth embodiment.

[0091] The operation monitoring and control system of the tenth embodiment includes a mobile object control server 60, a radio environment estimation system 50 configured by an electromagnetic field analysis server, a mobile object control device 71, and a mobile object monitoring device 81 as main components.

[0092] A mobile object control device 61 of the mobile object control server 60 manages the operation of the mobile object 2 within the mobile object control area. The mobile object 20 is equipped with a mobile object control device 71. The mobile object control device 71 wirelessly transmits an operation status signal of the mobile object 20 to the mobile object control device 61 via a terminal station radio 72 and a base station radio 62 connected to the mobile object control server 60. A mobile object monitoring device 81 acquires the position and attitude of the mobile object 20 in real space from devices such as a LiDAR 7 and a camera 8, and sends the acquired position and attitude information to the mobile object control server 60.

[0093] The mobile object control server 60 sends the information on the position and attitude of the mobile object 20 acquired from the mobile object monitoring device 81 to the wireless environment estimation system 50. In the wireless environment estimation system 50, the electromagnetic field calculation engine 51 calculates the electromagnetic field distribution within the mobile object control area based on the information on the position and attitude of the mobile object 20 received from the mobile object control server 60, and the wireless quality evaluation device 52 estimates wireless communication quality using the calculation result of the electromagnetic field distribution and sends the estimated wireless communication quality to the mobile object control server 60.

[0094] The mobile object control device 61 of the mobile object control server 60 formulates a control plan for stable and safe operation of the mobile object 20 based on the current wireless communication quality and predicted values ​​of future wireless communication quality of the mobile object 20 obtained from the wireless environment estimation system 50. The base station radio 62 sends the formulated management plan to the terminal station radio 72 via the mobile object control device 71.

[0095] 10b is a diagram showing the current estimated wireless communication quality state of the wireless system 101 as understood by the mobile object control server 60. In the figure, dark gray indicates areas with weak electric fields, and light gray indicates areas with slightly weak electric fields. Both of the two mobile objects 20 in the figure are located in areas with slightly weak electric fields, and some kind of action is required in the air traffic control to deal with the instability of the wireless communication link.

[0096] FIG. 10c is a diagram showing the future predicted state of wireless communication quality of the wireless system 101 as predicted by the mobile object control server 60. In FIG. 10c, as in FIG. 10b, dark gray indicates areas with weak electric fields, and light gray indicates areas with slightly weak electric fields. The two mobile objects 20 in the diagram are currently in an area where good wireless communication quality can be obtained, but there is a possibility that they will enter an area where wireless communication is difficult at a future time. In the air traffic control, it is necessary to notify the mobile objects 20 in advance that there is a possibility that the wireless communication line will be cut off, and to plan some kind of action to deal with the cut off of the wireless communication line.

[0097] According to this embodiment, in the remote control of a mobile body 20 using wireless communication, the current and future quality of the wireless communication line can be predicted, and a control plan can be formulated to ensure safe and stable operation of the mobile body 20, which is effective in ensuring stable and safe operation of the transportation system.

[0098] Example 11 An eleventh embodiment of the present invention will be described with reference to Fig. 11. In the eleventh embodiment, differences from the tenth embodiment will be mainly described, and the same configurations and processes as those in the tenth embodiment will be assigned the same reference numerals, and descriptions thereof will be omitted.

[0099] 11 is a diagram showing another example of the configuration of an operation monitoring and control system using a wireless digital twin according to Example 11. Example 11 differs from Example 10 in that an electromagnetic field analysis cloud 59 is provided instead of the wireless environment estimation system 50.

[0100] The operation monitoring and control system of the eleventh embodiment includes a mobile object control server 60, an electromagnetic field analysis cloud 59, a mobile object control device 71, and a mobile object monitoring device 81 as main components.

[0101] The electromagnetic field analysis cloud 59 executes the electromagnetic field analysis process executed by the wireless environment estimation system 50 of the tenth embodiment on a virtual computer constructed on a plurality of physical computer resources.

[0102] According to this embodiment, in the remote control of a mobile body 20 using wireless communication, the current and future quality of the wireless communication line can be predicted, and a control plan can be devised to ensure safe and stable operation of the mobile body 20, which is effective in ensuring stable and safe operation of the transportation system, and further has the effect of enabling mobile body control services to be expanded over a wide area.

[0103] The present invention is not limited to the above-described embodiments, but includes various modifications and equivalent configurations within the spirit and scope of the appended claims. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and the present invention is not necessarily limited to configurations including all of the described configurations. Furthermore, part of the configuration of one embodiment may be replaced with the configuration of another embodiment. Furthermore, the configuration of another embodiment may be added to the configuration of one embodiment. Furthermore, part of the configuration of each embodiment may be added, deleted, or replaced with other configurations.

[0104] Furthermore, the aforementioned configurations, functions, processing units, processing means, etc. may be realized in part or in whole in hardware, for example by designing them as integrated circuits, or may be realized in software by a processor interpreting and executing a program that realizes each function.

[0105] Information such as programs, tables, and files that realize each function can be stored in a storage device such as a memory, a hard disk, or an SSD (Solid State Drive), or in a recording medium such as an IC card, an SD card, or a DVD.

[0106] In addition, the control lines and information lines shown are those that are considered necessary for explanation, and do not necessarily represent all the control lines and information lines that are necessary for implementation. In reality, it can be assumed that almost all components are interconnected. [Explanation of symbols]

[0107] 1…Stationary structure 2...Mobile 3…road 4...Measurement surface 5...Base station 6...Terminal station 8...Camera 11...Ray 12...Micro segment 13...Micro segment 14...Micro segment 15...Micro segment 16...Micro segment 19...Transmission point 20...Mobile 21...Ray 22...flying object 24...Measurement closed surface 31...Ray 34...Measuring shell 41...Ray 44...Micro voxel 50...Wireless environment estimation system 51...Electromagnetic field calculation engine 52...Wireless communication quality evaluation device 59...Electromagnetic field analysis cloud 60...Mobile control server 61…Mobile object control device 62...Base station radio 71...Mobile control device 72...Terminal station radio 81...Mobile monitoring device 82...Base station radio 100...Wireless environment measurement system 101...Radio System 102...Radio system 103...Radio system 104...Radio system 105...Radio system 106...Radio System 300...Calculation engine 310...Electromagnetic field calculation control device 311...Secondary transmission point generating device 312...Moving object polygon generator 313...Structure polygon generator 314...receiving polygon generating device 320...Measuring area control device 321...Reception area generating device 322...Transmission point generation device 328...Base station location input device 329...Receiving area input device 330...Point cloud analysis device 331...Surface correction device 332...Mobile body model data generator 333...Surface conversion device 334...Point cloud storage device 339...Point cloud data measurement device 340...Structure data generation device 341...Structural database 342...Surface correction device 343...Surface conversion device 344…Point cloud storage device 345...Model data generation device 348...Point cloud data acquisition device 349...Structural data input device 350...Output control device 351... Field strength data storage device 352...Mobile data storage device 353...Display data generating device 359…Display device 360...Video analysis device 361...Structural database 362...Structural model database 363...Video Judgment Device 364...Model data generation device 365...Video storage device 369...Video recording equipment 501...processor 502...Memory 503…Auxiliary storage device 504...Communication interface 505...input interface 506...Keyboard 507...Mouse 508...Output interface 509...Display device

Claims

1. A radio environment estimation system, The computer is configured by an arithmetic unit that executes predetermined processing and a storage device connected to the arithmetic unit, the storage device holds stationary structure data including structure data of stationary structures within a wireless communication area, mobile body data including structure data of mobile bodies within the wireless communication area, and observation area data relating to an observation area of ​​an electromagnetic field; The computing device generating a first electromagnetic field analysis model for analyzing electromagnetic waves reflected by a stationary structure within the observation area using the stationary structure data and the observation area data; A primary wave source is set at the location of the radio station, generating a secondary transmission point from an electromagnetic field that is obtained by calculation using the first electromagnetic field analysis model and reaches the observation region; generating a second electromagnetic field analysis model for analyzing electromagnetic waves radiated from the secondary transmission point using the moving body data and the observation area data; A radio environment estimation system characterized in that the second electromagnetic field analysis model is used to calculate an electromagnetic field due to electromagnetic waves radiated in the opposite direction to the electromagnetic waves arriving at the secondary transmission point.

2. 2. The radio environment estimation system according to claim 1, The radio environment estimation system is characterized in that the observation area is a surface.

3. 2. The radio environment estimation system according to claim 1, A radio environment estimation system characterized in that the observation area is a measurement shell having a volume.

4. 2. The radio environment estimation system according to claim 1, A radio environment estimation system, characterized in that the observation area is set in an area where the moving object may be present.

5. 2. The radio environment estimation system according to claim 1, A radio environment estimation system characterized in that the structural data of the moving body is composed of polygons derived from a point cloud measured by LiDAR.

6. 2. The radio environment estimation system according to claim 1, the storage device stores reference image data and structural data of the moving object; A wireless environment estimation system, characterized in that the structural data of the moving object is structural data associated with reference image data similar to image data captured by a camera.

7. 6. The radio environment estimation system according to claim 5, The computing device Estimating the position of the moving object after a predetermined time using the moving direction and moving speed of the moving object derived from the LiDAR measurement results at multiple times; A radio environment estimation system, characterized in that the electromagnetic field after the predetermined time is calculated using the estimated position of the moving body.

8. 7. The radio environment estimation system according to claim 6, estimating a position of the moving object after a predetermined time using a moving direction and a moving speed of the moving object derived from image data captured by the camera at a plurality of times; A radio environment estimation system, characterized in that the electromagnetic field after the predetermined time is calculated using the estimated position of the moving body.

9. 2. The radio environment estimation system according to claim 1, dividing a surface on which the electromagnetic wave is observed by the stationary structure and a surface on which the electromagnetic wave is observed by the moving body into minute surface segments; A radio environment estimation system characterized in that an electromagnetic field is derived by calculating the interaction between the generated microsurface segments and rays that simulate electromagnetic waves using a ray tracing method.

10. 2. The radio environment estimation system according to claim 1, an electromagnetic field calculation engine for calculating an electromagnetic field due to electromagnetic waves within a wireless communication area; an electromagnetic field calculation control device that generates data used by the electromagnetic field calculation engine to calculate an electromagnetic field; a structure data generation device for generating the static structure data; a mobile object data generation device that generates the mobile object data; a measurement area control device that generates the observation area data; an output control device that outputs the calculation result of the electromagnetic field, the electromagnetic field calculation control device generates segments by dividing the surfaces of the stationary structure, the moving body, and the observation area of ​​the electromagnetic field used by the electromagnetic field calculation engine to calculate the electromagnetic field, based on the stationary structure data output from the structure data generation device, the moving body data output from the moving body data generation device, and the observation area data output from the measurement area control device; The electromagnetic field calculation engine calculates an electromagnetic field using the generated segments.

11. The radio environment estimation system according to claim 10, the measurement area control device receives input of the location of the base station and the electromagnetic wave characteristic measurement area within the wireless communication service area, The radio environment estimation system is characterized in that the output control device outputs data representing the electromagnetic field within the electromagnetic wave characteristic measurement area.

12. The radio environment estimation system according to claim 11, The radio environment estimation system is characterized in that the output control device outputs data representing radio waves propagating within the electromagnetic wave characteristic measurement area as rays.

13. The radio environment estimation system according to claim 12, A radio environment estimation system characterized by displaying the positions and shapes of the stationary structures within the radio communication service area and the positions and shapes of the moving bodies within the radio communication service area together with rays propagating within the electromagnetic wave characteristic measurement area.

14. A radio environment estimation method executed by a radio environment estimation system, comprising: the radio environment estimation system is configured by a computer having an arithmetic unit that executes predetermined processing and a storage device connected to the arithmetic unit; the storage device holds stationary structure data including structure data of stationary structures within a wireless communication area, mobile body data including structure data of mobile bodies within the wireless communication area, and observation area data relating to an observation area of ​​an electromagnetic field; The radio environment estimation method includes: the computing device generates a first electromagnetic field analysis model for analyzing electromagnetic waves reflected by stationary structures within the observation area using the stationary structure data and the observation area data; the computing device sets a primary wave source at the position of the wireless station; the calculation device generates a secondary transmission point from the electromagnetic field that is obtained by calculation using the first electromagnetic field analysis model and reaches the observation region; the computing device generates a second electromagnetic field analysis model for analyzing electromagnetic waves radiated from the secondary transmission points using the moving body data and the observation area data; A radio environment estimation method, characterized in that the calculation device uses the second electromagnetic field analysis model to calculate an electromagnetic field due to electromagnetic waves radiated in the opposite direction to the electromagnetic waves arriving at the secondary transmission point.

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