JP5081136B2 - Wireless communication device placement support system - Google Patents

Description

  The present invention relates to an arrangement support system that supports determination of an appropriate arrangement position of a wireless communication apparatus when a person or an object has the wireless communication apparatus having an IC chip and an antenna.

  When a wireless communication apparatus (for example, RFID) is attached to a person or an object, the characteristics of the antenna of the wireless communication apparatus greatly change due to the influence of the dielectric constant of the person or the object. Therefore, it is necessary to design using antenna characteristics including the influence of humans and objects. Therefore, as a conventional technique of an antenna characteristic analysis method including the influence of a person or an object, for example, the entire analysis space as in the FDTD (Finite Difference Time Domain) method described in Non-Patent Document 1. A method has been proposed in which electromagnetic field analysis is performed by dividing the data into voxels and successively expanding and calculating them using the difference method in space and time.

  In addition, since the arrangement support system for wireless communication devices requires analysis of the entire moving space, a technique for analyzing a large-scale space at high speed is required. Thus, for example, a ray tracing method disclosed in Patent Document 2 and an imaging method disclosed in Patent Document 3 have been proposed as conventional techniques for a high-speed analysis method that can deal with a large-scale space.

  The ray tracing method approximates the propagation of radio waves to the propagation of rays, and follows the principle of how light travels, where light travels straight in a uniform medium and reflects and refracts at different medium boundaries. In this method, the propagation path from the transmission point to the reception point is obtained geometrically. In ray tracing, only rays that have arrived at the reception position are subject to analysis, so high-speed analysis becomes possible. The imaging method is one of ray tracing methods, and is a technique for performing radio wave propagation analysis by replacing the mirror image position with respect to the reflecting surface with the real image position.

Furthermore, as described in Patent Document 1, effective antenna characteristics in an actual environment are obtained as a conventional technique for high-speed analysis of a large-scale space using antenna characteristics including the effects of humans and objects. When the ray launch method analysis is used, a method has been proposed in which only the main part of the radiation characteristic is calculated from the rays emitted from the transmission point.
JP 2005-333451 A JP 2001-28570 A Japanese Patent Laid-Open No. 10-62468 IEICE TRANS COMMUN VOL.E86-B, NO.6 JUNE 2003

  However, in the method disclosed in Non-Patent Document 1 described above, since the simulation is performed by dividing the space by voxels, the computation time increases as the analysis space increases. Further, in order to ensure the accuracy of the simulation, it is necessary to make the size of the voxel 1/6 or less of the wavelength, and there is a problem that the calculation time increases as the frequency increases. Furthermore, when performing analysis in consideration of the movement path, it is necessary to calculate the electric field strength for each point on the path, but in order to calculate one point, it is necessary to analyze the entire analysis space. An increase in time is inevitable. Further, since the entire analysis space is divided into voxels and sequentially expanded and calculated by the difference method, if communication becomes impossible at one point in the analysis space, it is difficult to identify the cause of the problem.

  In addition, the methods disclosed in Patent Document 2 and Patent Document 3 described above are not suitable for analysis when the antenna is close to the position of a person or an object because analysis is performed using a far field.

  Further, in the method disclosed in Patent Document 1 described above, the calculation accuracy is lowered because the calculation is performed using only the main part of the radiation characteristic among the light rays emitted from the transmission point. In addition, it is assumed that data is transmitted from a portable device, and analysis at a fixed reception position is described, and analysis with movement such as a person or an object is not supported.

  In addition, in order to accurately grasp the movement situation / entrance / exit situation in a multipath environment, an appropriate antenna arrangement is required, but in order to realize an appropriate antenna arrangement, the cause of the problem is identified. It is necessary to take countermeasures interactively. However, the method described in any of the above-mentioned patent documents and non-patent documents has a problem that it does not support such interactive processing.

  In view of the above-described problems, the present invention is an arrangement of a wireless communication apparatus that realizes an appropriate antenna arrangement by performing radio wave propagation analysis using antenna characteristics including the influence of a person or an object attached with the wireless communication apparatus. The purpose is to provide a support system.

In order to solve the above problems, the present invention mainly adopts the following configuration.
In a wireless communication device placement support system that performs a simulation in which a wireless communication device having an IC chip and an antenna communicates with a base station,
An antenna model creation unit that creates an antenna far-field omnidirectional pattern of the wireless communication device attached to a human or an object, and performs radio wave propagation analysis on an analysis space using the antenna far-field omnidirectional pattern and an ambient environment model An analysis execution unit to perform,
The antenna model creation unit includes an antenna input unit that inputs the type, shape, and characteristics of the antenna of the wireless communication device, and an attachment input that inputs the shape, characteristics, and mounting position of a person or object to which the wireless communication device is attached. Means, an antenna far-field omnidirectional pattern creating means for creating a far-field omnidirectional pattern of the antenna after being affected by a human or an object, and an antenna model DB for storing the created antenna far-field omnidirectional pattern And comprising
The analysis execution unit includes an antenna model selection unit that selects a target antenna model from the antenna model DB, an ambient environment model input unit that inputs information on an ambient environment including the wireless communication device and a base station, and the antenna A radio wave propagation analysis means for performing analysis on an analysis space using the model and the ambient environment model; and a display output means for displaying and outputting the radio wave intensity of the target analysis space. The radio wave propagation analysis for the analysis space is performed using the antenna characteristics and the ambient environment model, and the radio wave propagation analysis result is displayed and output.

  In the wireless communication device placement support system, a human model having the parameters of age, sex, height and body shape of the person to which the wireless communication device is attached, skin tomography and moisture content, and attachment position are parameters. A configuration in which a human model DB to be created and stored is further provided in the antenna model creation unit, and an appropriate human model is output from the human model DB to the attached body input means to provide an antenna model for each person; To do. Further, when the wireless communication device attached to the person or object moves, only the moving path input means for designating the moving path of the antenna in the wireless communication apparatus and the mesh grid points on the moving path are extracted. Means for determining an analysis space is further provided in the analysis execution unit, and radio wave propagation analysis is performed on an analysis space corresponding to mesh grid points on the movement path. Furthermore, a threshold value is provided for the radio wave intensity obtained by the radio wave propagation analysis by the radio wave propagation analyzing means, and the obtained radio wave intensity is compared with the threshold value to perform communication evaluation by the wireless communication device. . Furthermore, by selecting a communication impossible area in the analysis space displayed on the display output means, a ray reaching the communication disabled area is displayed and the cause of the communication failure is visualized and specified. .

  According to the present invention, an antenna characteristic including the influence of a person or an object is modeled in advance, so that an analysis including the influence of the person or the object can be performed even by a ray tracing method (imaging method or ray launch method). In addition, by performing radio wave propagation analysis using an antenna model created in advance, the calculation time can be greatly reduced.

  In addition, since the cause of communication failure can be visualized, the cause analysis work and the improvement work can be interactively performed, and an appropriate antenna arrangement can be realized. Furthermore, when the wireless communication apparatus of the present invention is used, it is possible to support position detection accuracy evaluation and the like.

  An arrangement support system for a wireless communication apparatus according to an embodiment of the present invention will be described in detail below with reference to the drawings.

“Outline of Wireless Communication Device Placement Support System According to Embodiment of Present Invention and Overall Configuration”
First, an outline of a wireless communication apparatus arrangement support system according to the present embodiment will be described using a specific example. 4, 8, and 9, a person or tool is attached to a person 44 or a pipe (which may be a repair tool) 46 by attaching a wireless communication device (eg, RFID tag) having an IC chip and an antenna 42. A simulator in a detection system that detects that a base station antenna 81, which is a base station, is installed on a gate or a wall on which the base station antenna 81 is installed is an object of the present invention. Such a detection system can be used, for example, in a facility or factory such as a nuclear power plant, and who has passed through a gate or a specific detection part (wall surface) (a base station that transmits and receives radio waves from a wireless communication device). In addition, RFID tags can be attached to all tools during periodic inspections and repairs of transport vehicles and plants, and can be used to check that tools are not forgotten when inspections and repairs are completed. .

  The placement support system according to the present embodiment is a simulator of the above-described detection system. The antenna characteristics including the effects of humans and objects are modeled in advance and stored in a database (DB). An appropriate modeled antenna model is selected, and an ambient environment model (a radio wave propagation ambient environment including a base station antenna 81 that is a base station that transmits and receives radio waves from or to the RFID tag) is created. Based on the ambient environment model and the above-described selected antenna model, an analysis is made as to how much electric field intensity can be received by the base station from the radio communication apparatus.

  In addition, the cause of the inability to communicate between the base station antenna (base station) and the RFID tag is visualized by a simulator, and an attempt is made to execute an analysis operation of a radio interference object and an improvement operation such as a shield or position change of the object while simulating. To do. Here, to give a specific example, the tag antenna 42 of the wireless communication device 43 receives the radio wave transmitted from the base station antenna 81, is powered by the power of the received radio wave, moves the IC chip 41, and returns a response signal. Thus, the base station antenna 81 or another adjacent receiving device can receive a response signal from the IC chip 41 as a base station and detect passage of a person or an object (tool). In this detection, a human or an object is detected at any location within a predetermined range (within the mesh range in FIG. 9) of the base station device (eg, base station antenna 81, that is, an antenna having a transmission / reception function). What should be done.

  Next, the configuration of a wireless communication apparatus arrangement support system according to an embodiment of the present invention will be described with reference to FIG. The wireless communication device arrangement support system includes an antenna model creation unit 1 and an analysis execution unit 2.

  The antenna model creation unit 1 includes an input unit 11 for the shape and characteristics of the antenna of the wireless communication device, a human or object input unit 12 to which the wireless communication device is attached, for example, an electromagnetic current such as the FDTD (finite difference time domain) method. The analysis unit 13 includes a far field analysis unit 14 based on an equivalent theorem from a near field obtained by FDTD, an antenna far field omnidirectional pattern generation unit 15, and an antenna model DB 16. The analysis execution unit 2 includes an antenna model selection unit 17, an ambient environment model input unit 18, a radio wave propagation analysis unit 19 for an analysis space, and an output unit 20.

  Specifically, as step 1, the antenna input means 11 of the wireless communication apparatus is a means for inputting the type, shape, and characteristics of the antenna of the wireless communication apparatus attached to a person or an object. As step 2, the person or object input means 12 to which the wireless communication apparatus is attached is means for inputting the shape, characteristics, and attachment position of the person or object to which the wireless communication apparatus is attached. Further, as step 3, the electromagnetic current analyzing means 13 such as the FDTD method is a means for calculating the electromagnetic current of the antenna after being influenced by a person or an object. In this analysis method, for example, the Maxwell equation is differentiated on the basis of the information on the antenna, the person, and the object described above, and the electromagnetic current is calculated by the FDTD method in which the analysis is performed by the Yee algorithm.

  FIG. 4 shows an example of the antenna model. The wireless communication device 43 includes an IC chip 41 and a tag antenna 42. Since the antenna characteristics of the wireless communication device when a person or an object is approaching are different from the case of handling alone, the antenna model 45 when the wireless communication device 43 is attached to the position of the chest pocket of the human 44 or the wireless communication device 43. Is attached to the pipe or the tool 46 as an analysis target.

  Next, as step 4, the far-field analysis means 14 based on the equivalence theorem is means for estimating the far-field from the near-field electromagnetic flow obtained by the FDTD method. When the FDTD method is normally used, each voxel up to a distance must be calculated every time, which consumes enormous calculation time and memory. Therefore, the far field is estimated from the nearby electromagnetic field. Specifically, using the equivalence theorem, a closed surface surrounding the wave source is created, and when the electromagnetic field in the closed surface is zero, the electromagnetic flow that flows on the closed surface from the boundary condition is regarded as the wave source, and radiation from there think of. By such an equivalent theorem, the far field is obtained from the electromagnetic current obtained by the FDTD method.

  Further, as step 5, the antenna far-field omnidirectional pattern creating means 15 is a means for creating an antenna far-field omnidirectional pattern table or an antenna far-field omnidirectional pattern based on θ and φ. Here, θ and φ are defined by FIG. That is, θ is a rotation angle from the z direction, and φ is a rotation angle from the x direction. Based on the observation result while rotating the far observation point in the θ and φ directions with reference to the antenna position o, the antenna far field omnidirectional pattern table 61 by θ and φ in FIG. 6 and the antenna far field in FIG. A direction pattern 71 is obtained. Next, as step 6, the antenna model DB (database) 16 is a means for storing the antenna far-field omnidirectional pattern 71 obtained by the pattern creating means 15. The creation of the antenna model is completed through the above steps.

  Next, the analysis execution unit 2 will be described. In step 7, the antenna model selection means 17 selects a target antenna model from the antenna model DB 16 created by the antenna model creation unit 1 (for example, the antenna model 45 including the human model shown in FIG. This is a means for selecting the field radiation pattern 71). Further, as step 8, the ambient environment model input means 18 is a means for inputting the shape, characteristics, and position of the ambient environment. As shown in FIG. 8, a base station antenna 81 (acts as a base station that transmits radio waves to the tag antenna 42 of the wireless communication device 43 to enable the IC chip 41 to operate and receives radio waves from the tag antenna 42) or radio waves An ambient environment model 83 such as an object 82 or a pipe 46 that affects propagation is created.

  In step 9, the radio wave propagation analyzing means 19 for the analysis space is a means for performing a radio wave propagation analysis for the analysis space using the antenna far-field omnidirectional pattern 71 and the ambient environment model 83 described above. It is. That is, radio wave propagation analysis is performed to determine what electric field intensity is present at the base station due to radio waves transmitted from the wireless communication device.

  The analysis space to be subjected to the radio wave propagation analysis corresponds to a hatched portion formed by mesh lattice points arranged at intervals of dx, dy, dz in the x, y, z axial directions as shown in FIG. The received power at one mesh mesh point is obtained by the process of FIG. FIG. 11 shows an example in which radio wave propagation analysis is performed by the ray tracing method. A case will be described as an example where a plurality of rays r1 (112), rays r2 (113), and rays r3 (114) have arrived at the reception point C (110) in FIG.

  Reference numeral 121 in FIG. 12 denotes a component of a ray that has reached the reception point C, which is a mesh lattice point. The ray component 121 can be expressed by the incident angles θri and φri and the electric field strength Dri for each ray. Reference numeral 122 denotes the antenna far-field omnidirectional pattern G (θ, φ) described above, which is obtained from the incident angles θ and φ from the table of FIG.

The electric field intensity at the reception point C by the ray ri is selected from the electric field intensity Dri for the incident angles θri and φri of the ray ri and the antenna far-field omnidirectional pattern Gri in the direction from FIG. It is obtained by the product of Gi (Gi route) and Dri (where i is the ray number). G (θri, φri) = Gri (Equation 1)
Therefore, the electric field intensity E at the reception point by all the rays can be calculated by the following equation (2).

The reception power P at the reception point C is obtained by the following equation 3 using the electric field strength E at the reception point.

P = 20 log E (Equation 3)
Next, as step 10, the output means 20 is a means for outputting a calculation result by the radio wave propagation analyzing means 19 shown in FIG. For example, there is means for displaying the electric field strength in the analysis target space of FIG.

  As described above, according to the configuration example of the wireless communication apparatus arrangement support system according to the present embodiment, the ray tracing method (imaging method or The analysis including the influence of humans and objects is possible even with the lailaunch method. In addition, since the antenna model created in advance in step 5 is handled as a receiving antenna of the ray tracing method and radio wave propagation analysis is performed, high-speed analysis becomes possible.

"Creating a human model"
A means for creating a human model to which a wireless communication device is attached will be described. In order to improve the analysis accuracy, it is necessary to improve the accuracy of the human model. In creating an antenna model that includes human influences, in order to provide an individual antenna model, parameters such as human age, sex, body shape (height, weight) and characteristics (skin tomography, moisture content) are parameters. It is necessary to create a human model.

  Next, the configuration of a wireless communication apparatus arrangement support system that creates an antenna model by handling a human model will be described with reference to FIG. The wireless communication apparatus arrangement support system has a configuration in which a human model DB 21 is added as a pre-stage of the input means 12 of the person 44 and the object 46 to which the wireless communication apparatus 43 of FIG. The human model DB 21 is obtained by collecting and organizing data obtained by an electromagnetic wave analysis method or actual measurement and creating a human model table 131 as shown in FIG. Thereafter, by creating a human model using the human model DB 21 when creating the antenna model, it becomes possible to provide an antenna model for each individual, and the analysis accuracy of the arrangement support system of the wireless communication device is improved.

"Analysis space for performing radio wave propagation analysis"
The analysis space of the arrangement support system according to the present embodiment is a hatched portion in FIG. Although it is possible to analyze the whole, it is necessary to make the analysis space as small as possible in order to shorten the analysis time. In the present embodiment, a means for performing calculation by narrowing the analysis space to a movement path of a person or an object will be described.

  As a specific example, when the human 44 walks with the wireless communication device 43 in the chest pocket (see FIG. 4), it is not necessary to examine the communication characteristics of the mesh points of the mesh in the entire analysis space. If only mesh grid points on the movement path of the wireless communication device 43 are extracted from the mesh grid points and the communication characteristics are grasped for the corresponding analysis space, the wireless communication devices can be arranged.

  First, an outline of the configuration of the wireless communication apparatus arrangement support system will be described with reference to FIG. The wireless communication apparatus arrangement support system adds a movement path input means 31 to the ambient environment model input means 17 of FIG. 1, and further, meshes on the movement path immediately before the radio wave propagation analysis means 19 for the analysis space. It has a configuration in which means 32 for extracting the lattice points and determining the analysis space is added. The movement path input means 31 is a means for designating an antenna movement path. The movement path has the form of a line in FIG. 14 (1), the form of a surface in FIG. 14 (2), and the form of a space in FIG. 14 (3). In addition, the movement path of humans and objects can be managed by taking in the movements of humans and objects.

  The means 32 for extracting the mesh lattice points on the movement path and determining the analysis space extracts only the mesh lattice points (hatched portions) on the movement path of the wireless communication device from the mesh points of the mesh in the entire analysis space, and responds to it. This is a means for performing radio wave propagation analysis on the analysis space to be analyzed. The grid points of the mesh on the movement path correspond to the hatched portions in FIG.

  Therefore, it is not necessary to perform the calculation for the entire analysis space, and it is possible to contribute to the shortening of the analysis time and the saving of memory by setting only the movement path as the calculation target. Although the above description has been given by taking the case of one-way communication as an example, it can be similarly applied to reverse communication and two-way communication. Further, the transmission / reception wireless communication apparatuses do not necessarily have to be one-to-one, and can be applied to a plurality of cases.

  As described above, radio wave propagation analysis is performed only on the path (mesh grid point shown in FIG. 10) on which the wireless communication device 43 moves, that is, the antenna model of the wireless communication device 43 attached to the person 44 shown in FIG. Analysis of reception sensitivity at the base station antenna 81 when 45 is located at each mesh lattice point in FIG. 10 is performed. At this time, when the wireless communication device 43 passes all the mesh grid points of the moving path, there is no problem if the reception sensitivity at the base station antenna 81 is good, but the surroundings such as the object 82 shown in FIG. It is possible to analyze by simulation that the reception sensitivity at a certain mesh lattice point is insufficient for communication depending on the environment, and it is possible to display the simulation result and track the cause of reception sensitivity shortage This is one of the features of this embodiment.

"Displaying communication characteristics when a travel route is specified"
The result obtained by radio wave propagation analysis is the level of radio waves. Whether or not the wireless communication device can communicate with the arrangement of the wireless communication device 43 depends on whether or not the strength of the radio wave is a value necessary for communication of the wireless communication device. Therefore, a method will be described in which a minimum radio wave intensity necessary for communication of the wireless communication apparatus is set as a threshold value, and when the threshold value is exceeded, communication is possible, and in the opposite case, communication is impossible.

  Next, details of an example in which a movement route is designated will be described with reference to FIGS. 15 and 16. In these figures, human traffic lines are shown and the electric field strength received by the base station is shown. As a method for displaying the communication characteristics, there are a form in which the communication rate is displayed, and a form in which the communication characteristics are displayed separately for communicable and incapable communication. The communication rate is displayed in the form of displaying the communication rate of each section of the moving route as shown in FIG. 15 (1) or in several stages as shown in FIG. 15 (2). There is a form to display.

  In addition, the display mode can be divided into communication enablement and communication disablement, as shown in FIG. 16 (1), displayed in different colors as shown in FIG. 16 (2), displayed in different backgrounds as shown in FIG. As shown in 3), a communicable section is displayed with a symbol “O”, and a non-communication section is displayed with a symbol “x”, as shown in FIG. 16 (4), as a message, or as shown in FIG. 16 (5). There is a form in which one of them is illuminated as shown in FIG. 16 and a form in which only one of the communicable area and the incommunicable area is displayed as shown in FIG. In FIG. 16 (6), it is displayed in dark gray on the left side (unreadable) and light gray on the right side that can be read (intermediate left and right regions are difficult to read). Since the unreadable area is a noticeable part, the part that draws attention is represented by a conspicuous color or darkness. Note that the stepped display on the right side of FIG. 16 (6) indicates the reception sensitivity for each mesh grid point in the human flow line. Although the above-described example has been described by taking a flat display as an example, it can be similarly applied to a stereoscopic display and a wire display.

  Here, the threshold value of the communicable / impossible area is determined based on the characteristics of the wireless communication apparatus, by the method of specifying by input, or by the vertical bar at the right end (gray is divided into five stages in order as shown in FIG. 16 (7)). There is a method of specifying by dragging the lower end of the vertical bar corresponding to the communicable area and the upper end corresponding to the incommunicable area. Since the communication characteristic display screen of the movement path can be enlarged / reduced or moved in a plane, and can be rotated as shown in FIG. 16 (8), the result can be analyzed from various viewpoints. By displaying the value of the electromagnetic field as communication characteristics, it is possible to quickly determine whether communication is possible and to contribute to reducing human errors.

"Visualization of the cause of communication failure"
Next, an outline of visualization of the cause of communication failure will be described by taking a case where a movement route is designated as an example. It is not necessary for all sections of the movement path to be communicable, and if communication is possible in one section on the movement path, it can be said that the system is communicable (a wireless communication device installed in a moving person) And the base station antenna, which is the base station, can communicate with each other if it can communicate in at least one section). By the way, when communication is impossible over the entire movement route or when an antenna arrangement that maximizes the communicable section is required, it is necessary to identify the cause of communication failure and take measures to solve the cause. Therefore, in this configuration example, a method for identifying an object (radio wave obstacle) causing communication failure by using ray tracing, for example, and visualizing the cause of communication failure with a ray will be described.

  There are two ray tracing methods, an imaging method and a ray launch method. The outline of each ray display method will be described below with reference to FIGS. 17 and 18. The imaging method is a radio wave propagation analysis method in which a mirror image position with respect to a reflection surface is replaced with a real image position. The procedure will be described by taking as an example a case where the ray radiated from the transmission point O is reflected by the reflection surface 1 and reaches the reception point C as shown in FIG. First, the mirror image point B of the reception point C is obtained using the reflection surface 1 as a reference. Let A be the intersection of the reflecting surface 1 by connecting the transmission point O and the point B. A ray to be obtained is obtained by sequentially connecting the transmission point O, the point A, and the reception point C.

  The ray launch method is a radio wave propagation analysis method for calculating a portion of a radio wave radiated from a transmission point that reaches a sphere or a cube with the reception point as a reference. As shown in FIG. 18, when a ray radiated from the transmission point O reaches a sphere or a cube with the reception point C as a reference by the law of reflection, OAC and OC are rays to be obtained.

  When an incommunicable section is selected with the keyboard or mouse, the ray that has reached the incommunicable section is calculated by the above method, and the shape of the ray is displayed three-dimensionally. In addition, the ray is displayed in a color-coded manner for each route as shown in FIG. 19 (1), displayed according to the thickness of the line as shown in FIG. 19 (2), or as shown in FIG. 19 (3). There is a form to display depending on the type of line. In the communication between the wireless communication device 43 and the base station (eg, the base station antenna 81), the electric field strength from the wireless communication device and the electric field strength from the base station show the same tendency. For convenience, whether or not communication is possible based on radio wave propagation analysis from the base station is taken up and described.

  Further, as a form in which only the ray to be observed is highlighted in the displayed ray 171, a form in which only the ray to be emphasized is displayed as shown in FIG. 20 (1) (for example, r 3 in FIG. 23), or FIG. ) To display the ray to be emphasized in different colors (for example, r1 and r3 in FIG. 23), or form to display only the ray to be emphasized as shown in FIG. 20 (3). In the above description, the communication section and the incommunicable section are described by way of example of color display. However, other forms of communication display can be similarly applied.

  By displaying the ray from the transmission position to the reception position at the location where communication is impossible, the communication route can be accurately and quickly grasped. In addition, in order to visualize which ray has a bad influence on the composite wave, it is necessary to display not only the size of the ray but also the phase. As a means for simultaneously displaying the magnitude and phase of a ray, a method of displaying a ray and a synthesized wave in a complex space is used. By displaying in a complex space, it is possible to visualize a ray that affects the combined wave. The complex display of rays is obtained by the process of FIG.

The electric field strength of the ray ri at the reception point is calculated from the value of the component 121 of the ray that has reached the mesh lattice point in FIG. 12 and the value of the receiving antenna far-field pattern (complex number) 122 using the following equation (4).

  Reference numeral 211 denotes the electric field intensity of the ray ri at the reception point, which is represented by the ray intensity E of 212 and the phase ωt of ray 213.

Further, based on the ray intensity 212 and the ray phase 213 obtained above, the ray complex display real part 214 and the ray complex display imaginary part 215 are obtained using the following equation (5).

  By the above calculation procedure, the complex wave real number part and the imaginary number part of the direct wave 222, the reflected wave 223, and the synthesized wave 221 that have reached a certain point on the moving path are obtained, and the calculation results are shown on the complex coordinates in FIG. indicate.

  Furthermore, as shown in FIG. 23, the cause of the communication failure is visualized by associating the above-described FIG. 22 with the ray route display screen and simultaneously performing an operation by the processing of FIG. First, a process 241 for specifying a ray that has a bad influence on the strength of the combined wave 221 on the complex display screen of the ray, for example, a reflected wave 231 is performed, and a process 242 for selecting with a mouse or a keyboard is performed. A process 243 in which the corresponding reflected wave 232 on the ray route display screen is selected by associating the complex display screen with the ray route display screen, and a process in which the obstacle 233 that causes the reflected wave is selected. 244 is automatically performed. Finally, the reflected wave 231 on the ray complex display screen, the corresponding reflected wave 232 on the ray route display screen, and the obstacle 233 causing the reflected wave are highlighted as a set. By the above-described method, the cause of communication failure can be visualized, and the countermeasure target can be identified accurately and quickly.

“Analysis and Countermeasure of Cause of Communication Failure”
In this configuration example, a method for analyzing the cause of communication failure from the display result and taking a countermeasure will be described. First, as shown in FIG. 25, an output result analysis process 251 of the placement support system according to the present embodiment is performed, and a determination process 252 for determining whether or not the radio wave characteristics need to be improved is performed. If it is not necessary, the work ends. If improvement is necessary, a determination process 253 is performed to determine whether adjustment work is possible. If the adjustment is not possible, the operation ends.

  If possible, the adjustment operation 254 is performed by any of the obstacle position / angle adjustment of FIG. 26 (1), the position / angle adjustment operation of the base station antenna, the movement route, and the operation of shielding the obstacle of FIG. 26 (2). (Work on the simulator). After the adjustment is completed, the reanalysis operation 255 is performed, and the process returns to the output result analysis process 251. By repeatedly adjusting in this way, the radio wave environment is improved.

"Evaluation of position detection accuracy using wireless communication devices"
In this configuration example, a position detection accuracy evaluation system using a wireless communication apparatus according to this embodiment will be described. As a position detection system, there is a method in which radio waves emitted from wireless terminals are received by two base stations as shown in FIG. 27, arrival times are replaced with distances, and position coordinates are calculated using trigonometry. Since this method is based on the premise that communication from a wireless terminal to a base station is a direct wave, high accuracy can be obtained in an environment without multipath. However, when the direct wave is blocked by an object, the signal received by the base station is due to the reflected wave, the propagation path becomes longer than the direct wave, and the position detection accuracy decreases.

  In the situation where there is no multipath as shown in FIG. 27 (1), the exact position 273 of the object is obtained by the routes R1, R2, and R3. However, when the object 272 is arranged between the object 273 and the base station 271 as shown in FIG. 27 (2), the direct wave from the object 273 does not reach the base station 271, and the reflected waves of the routes R21 and R22 Will be received. If the position coordinates are calculated by trigonometry using the routes R1, R21 + R22, R23, a detection result 274 as shown in FIG. 27 (3) is obtained. When the arrangement support system according to the present embodiment is used, the signal received by the base station can be visualized, so that it is possible to evaluate how much the detection position 274 is shifted from the accurate position 273.

  As shown in FIG. 28, the space to be evaluated is divided into several areas in advance, the above-described method is applied to each area, accuracy evaluation is performed, and accuracy information of each area is displayed to create an accuracy map. Can do. Although the above-described configuration example has been described for two base stations, it can be similarly applied to the case of two or more base stations. Moreover, the creation of increased accuracy can be handled not only in a plane but also in a three-dimensional space by increasing the number of base stations.

  As described above, the feature of the placement support system (simulation system) according to the embodiment of the present invention is that the antenna characteristics including the effects of humans and objects are modeled in advance, and radio wave propagation analysis is performed using this antenna model. By selecting an incommunicable section from the displayed communication characteristics results, the ray that has reached this incommunicable section is displayed, and at the same time, the ray is displayed in complex space, which object This makes it possible to visualize whether or not the reflection or shielding caused by the cause of communication failure, and to take measures corresponding to the cause to improve the communication characteristics.

It is a block diagram of the arrangement | positioning assistance system of the radio | wireless communication apparatus which concerns on embodiment of this invention. It is a block diagram at the time of using a human model in the arrangement | positioning assistance system of the radio | wireless communication apparatus which concerns on this embodiment. It is a block diagram at the time of designating a movement path | route with the arrangement | positioning assistance system of the radio | wireless communication apparatus which concerns on this embodiment. It is a conceptual diagram of the antenna model regarding this embodiment. It is a conceptual diagram of the far field and coordinate system regarding this embodiment. It is an example of the antenna far-field omnidirectional pattern table by (theta) and (phi) regarding this embodiment. It is an example of the antenna far-field omnidirectional pattern regarding this embodiment. It is an example of the surrounding environment model regarding this embodiment. It is an example of the radio wave propagation analysis which made analysis space the object regarding this embodiment. It is an example of the radio wave propagation analysis by a movement path | route regarding this embodiment. It is an example at the time of performing a radio wave propagation analysis by the ray tracing method regarding this embodiment. It is a calculation procedure figure of the reception power in the receiving point regarding this embodiment. It is an example of the human model table regarding this embodiment. It is an example of the movement path | route in the radio | wireless communication apparatus regarding this embodiment. It is an example of the communication characteristic result displayed by a communication rate regarding this embodiment. It is an example of the communication characteristic result which divides and displays for communication possible and communication impossible regarding this embodiment. It is an image figure which displays a ray by the imaging method regarding this embodiment. It is an image figure which displays a ray by the ray launch method regarding this embodiment. It is an example which displays all the rays which reached | attained the communication impossible area regarding this embodiment. It is an example which highlights only the ray which wants to observe in the ray which reached | attained the communication impossible area regarding this embodiment. It is a calculation procedure figure of the complex component of the ray regarding this embodiment. It is an image figure which displays a ray by a complex coordinate system regarding this embodiment. It is an example of the means which visualizes the cause of communication failure regarding this embodiment. It is a visualization procedure figure of the cause of communication failure concerning this embodiment. It is a procedure figure which takes measures about the part which becomes the cause of a communication failure regarding this embodiment. It is a countermeasure image figure of the communication failure regarding this embodiment. It is an example which shows the position detection accuracy evaluation system using the trigonometric method regarding this embodiment. It is an example of the position detection accuracy map regarding this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Antenna model preparation part 2 Analysis execution part 11 Antenna input means of radio | wireless communication apparatus 12 Input means of a human or an object which attaches a radio communication apparatus 13 Electromagnetic current analysis means like FDTD method 14 Far-field analysis means by equivalent theorem 15 Antenna Far-field omnidirectional pattern creation means 16 Antenna model DB
17 Antenna Model Selection Unit 18 Ambient Environment Model Input Unit 19 Radio Wave Propagation Analysis Unit Targeting Analysis Space 20 Output Unit 21 Human Model DB
31 Moving path input means 32 Means for extracting mesh grid points on moving path and determining analysis space 41 IC chip 42 Antenna 43 Wireless communication device 44 Human 45 Human antenna model 46 Object such as pipe or tool 47 Object antenna model 61 θ , Φ antenna far-field omnidirectional pattern 71 antenna far-field omnidirectional pattern 81 base station antenna 82 object 83 ambient environment model 110 reception point C
111 Transmission store O
112 Ray 1
113 Ray 2
114 Ray 3
121 Ray component reaching mesh grid point 122 Receiving antenna far-field pattern (complex)
123 Field strength at reception point 124 Reception power 131 Human model table 171 Ray display 211 Ray field strength at reception point 212 Ray strength 213 Ray phase 214 Ray complex display real part 215 Ray complex display imaginary part 221 Synthetic wave of all waves 222 Direct wave 223 Reflected wave 231 Ray on complex display screen 232 Ray on ray root display screen 233 Obstacle 241 Ray identifying means affecting synthetic wave on complex display screen 242 Complex display screen Ray selection means that affects the combined wave 243 Ray selection means that affects the combined wave on the ray route display screen 244 Obstacle selection means that causes a ray that affects the combined wave on the ray route display screen 245 Ray and obstacle emphasis display means 251 output result analysis means 252 radio wave characteristics Means for determining whether or not improvement is required 253 Means for determining whether adjustment work is possible 254 Adjustment means 255 Re-analysis means 256 Means for determining whether work is to be completed 261 Shield 271 Base station 272 Object 273 Accurate position of object 274 Object detection position 281 Accuracy A area 282 Accuracy D area

Claims (10)

In a wireless communication device placement support system that performs a simulation in which a wireless communication device having an IC chip and an antenna communicates with a base station,
An antenna model creation unit that creates an antenna far-field omnidirectional pattern of the wireless communication device attached to a human or an object, and performs radio wave propagation analysis on an analysis space using the antenna far-field omnidirectional pattern and an ambient environment model An analysis execution unit to perform,
The antenna model creation unit includes an antenna input unit that inputs the type, shape, and characteristics of the antenna of the wireless communication device; Means, an antenna far-field omnidirectional pattern creating means for creating a far-field omnidirectional pattern of the antenna after being affected by a human or an object, and an antenna model DB for storing the created antenna far-field omnidirectional pattern And comprising
The analysis execution unit includes an antenna model selection unit that selects a target antenna model from the antenna model DB, an ambient environment model input unit that inputs information on an ambient environment including the wireless communication device and a base station, and the antenna A radio wave propagation analysis means for performing analysis on an analysis space using a model and the ambient environment model, and a display output means for displaying and outputting the radio wave intensity of the target analysis space,
A radio communication apparatus characterized by performing radio wave propagation analysis on an analysis space using the antenna characteristics of the selected antenna model and using the ambient environment model, and displaying and outputting the result of the radio wave propagation analysis. Placement support system. In claim 1,
A human model DB for creating and storing a human model with parameters of the age, sex, height and body shape of the person to which the wireless communication device is attached, the characteristics of the skin tomography and water content, and the attachment position as parameters. In addition to the model creation department,
An arrangement supporting system for a wireless communication apparatus, wherein an appropriate human model is output from the human model DB to the attached body input means to provide an antenna model for each individual. In claim 1,
When the wireless communication device attached to the person or an object moves, only the moving path input means for specifying the moving path of the antenna in the wireless communication apparatus and the mesh lattice points on the moving path are extracted and analyzed. A means for determining a space, further provided in the analysis execution unit,
A radio communication apparatus placement support system, wherein radio wave propagation analysis is performed on an analysis space corresponding to mesh grid points on the movement path. In claim 1, 2 or 3,
A threshold is provided for the radio wave intensity obtained by the radio wave propagation analysis in the radio wave propagation analysis means,
The wireless communication device placement support system, wherein the wireless communication device performs communication evaluation by comparing the obtained radio wave intensity with the threshold value. In claim 1, 2 or 3,
By selecting an incommunicable area in the analysis space displayed on the display output means, a ray reaching the incommunicable area is displayed and the cause of incompatibility is visualized and specified. Wireless communication device placement support system. In claim 5,
Arrangement of radio communication apparatus, wherein radio wave propagation analysis is repeated by performing arrangement change, shielding process, or movement path change of radio communication apparatus causing radio communication obstacle causing the communication failure Support system. In claim 1,
When the radio communication device and at least two base stations are arranged in the analysis space, and a direct wave does not reach the base station due to a radio wave interference object in the analysis space, the reflected wave is routed. An arrangement support system for a wireless communication device, wherein the accuracy of position detection of the wireless communication device can be evaluated by displaying and displaying a ray. In a wireless communication device placement support system that performs a simulation in which a wireless communication device having an IC chip and an antenna communicates with a base station,
An antenna model creation unit that creates an antenna far-field omnidirectional pattern of the wireless communication device attached to a human or an object, and performs radio wave propagation analysis on an analysis space using the antenna far-field omnidirectional pattern and an ambient environment model An analysis execution unit to perform,
The antenna model creation unit includes an antenna input unit that inputs the type, shape, and characteristics of the antenna of the wireless communication device, and an attachment input that inputs the shape, characteristics, and mounting position of a person or object to which the wireless communication device is attached. Means, an antenna far-field omnidirectional pattern creating means for creating a far-field omnidirectional pattern of the antenna after being affected by a human or an object, and an antenna model DB for storing the created antenna far-field omnidirectional pattern And comprising
The analysis execution unit includes an antenna model selection unit that selects a target antenna model from the antenna model DB, an ambient environment model input unit that inputs information on an ambient environment including the wireless communication device and a base station, and the antenna A radio wave propagation analysis means for performing analysis on an analysis space using a model and the ambient environment model, and a display output means for displaying and outputting the radio wave intensity of the target analysis space,
When the wireless communication device attached to the person or an object moves, only the moving path input means for specifying the moving path of the antenna in the wireless communication apparatus and the mesh lattice points on the moving path are extracted and analyzed. A means for determining a space, further provided in the analysis execution unit,
When the movement route is designated, the minimum radio wave intensity required for communication between the base station and the wireless transmission device is set as a threshold, communication is not possible when the threshold is less than the threshold, and communication is possible when the threshold is exceeded. Display for each section of the travel route on the output means,
As a form of the display, a wireless communication apparatus characterized by displaying by color, displaying with different backgrounds, displaying with symbols, displaying with messages, or displaying only incommunicable sections or displaying with dark colors Placement support system. In a wireless communication device placement support system that performs a simulation in which a wireless communication device having an IC chip and an antenna communicates with a base station,
An antenna model creation unit that creates an antenna far-field omnidirectional pattern of the wireless communication device attached to a human or an object, and performs radio wave propagation analysis on an analysis space using the antenna far-field omnidirectional pattern and an ambient environment model An analysis execution unit to perform,
The antenna model creation unit includes an antenna input unit that inputs the type, shape, and characteristics of the antenna of the wireless communication device; Means, an antenna far-field omnidirectional pattern creating means for creating a far-field omnidirectional pattern of the antenna after being affected by a human or an object, and an antenna model DB for storing the created antenna far-field omnidirectional pattern And comprising
The analysis execution unit includes an antenna model selection unit that selects a target antenna model from the antenna model DB, an ambient environment model input unit that inputs information on an ambient environment including the wireless communication device and a base station, and the antenna A radio wave propagation analysis means for performing analysis on an analysis space using a model and the ambient environment model, and a display output means for displaying and outputting the radio wave intensity of the target analysis space,
When the wireless communication device attached to the person or an object moves, only the moving path input means for specifying the moving path of the antenna in the wireless communication apparatus and the mesh lattice points on the moving path are extracted and analyzed. A means for determining a space, further provided in the analysis execution unit,
When the movement route is designated, the minimum radio wave intensity required for communication between the base station and the wireless transmission device is set as a threshold, communication is not possible when the threshold is less than the threshold, and communication is possible when the threshold is exceeded. Display for each section of the travel route on the output means,
By selecting the incommunicable section, the ray that has reached the incommunicable section is calculated, and the shape of the ray is displayed in three dimensions,
As the form of the three-dimensional display, it is possible to visualize and specify the cause of communication failure by displaying by color for each route of the ray, displaying by line thickness, or displaying by line type. Wireless communication device placement support system. In claim 9,
As a form of highlighting only the ray to be observed among the displayed rays, only the ray to be emphasized is displayed, only the ray to be emphasized is displayed in a different color, or only the ray to be emphasized is lit and displayed, A wireless communication device placement support system characterized by grasping a communication path in an incommunicable section.