Radio Control System

Abstract

The present invention provides a radio wave control system 1 for increasing radio wave intensities in a wide area. The radio wave control system 1 comprises: a phase adjusting plate 10 that transmits radio waves from a second main surface to a first main surface and focuses the radio waves at a focal point; and a reflecting plate 20 installed in a position to be irradiated with the radio waves transmitted through the phase adjusting plate 10.

Description

[Technical Field]

[0001] The present invention relates to a radio wave control system for controlling radio waves for wireless communication. [Background technology]

[0002] Conventionally, a configuration in which an antenna or a concentrator is provided outdoors or on a window in order to improve indoor radio wave reception performance has been known. For example, Patent Document 1 proposes an antenna device in which a concentrator is provided on the indoor side of a window to collect radio waves and improve indoor radio wave reception performance. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2002-237717 Summary of the Invention [Problem to be solved by the invention]

[0004] The concentrator described in Patent Document 1 can concentrate power at the indoor focal point, but does not have the effect of concentrating radio waves at locations other than the indoor focal point.

[0005] Therefore, when electronic devices such as smartphones and laptops are used in different locations indoors or in multiple locations simultaneously, the reception performance of the electronic devices may deteriorate.

[0006] The present disclosure provides a radio wave control system that can improve radio wave strength over a wide range. [Means for solving the problem]

[0007] The present disclosure provides a phase adjustment plate that transmits radio waves from a second principal surface to a first principal surface and focuses the radio waves to a focal point; a reflector that is installed at a position where the radio waves that have passed through the phase adjustment plate are irradiated. A radio wave control system is provided. [Effects of the Invention]

[0008] According to the present disclosure, in a radio wave control system, it is possible to improve radio wave strength over a wide range. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a schematic diagram of a radio wave control system according to a first embodiment of the present invention. [Figure 2] FIG. 2 is a cross-sectional view of a glass plate with a phase adjustment plate according to the first embodiment. [Figure 3] FIG. 2 is a diagram illustrating the operation principle of the radio wave control system according to the first embodiment. [Figure 4] 3A and 3B are diagrams showing an example of a conductor pattern provided on the phase adjustment plate of the first embodiment. [Figure 5] 10 is a conceptual diagram of the reflection angle when the reflector of the present invention is a reflectarray. [Figure 6] An explanatory diagram of the mechanism for adjusting the reflection angle at each cell of the reflectarray, where radio waves that have passed through the phase adjustment plate are incident. [Figure 7] 1 is a schematic block diagram of a radio wave control system according to a first embodiment. [Figure 8] A diagram of a calculation model for simulating the electric field of radio waves transmitted through a phase adjustment plate. [Figure 9] 10 is a diagram showing the electric field strength and phase of radio waves transmitted through a phase adjustment plate at various distances from the phase adjustment plate. [Figure 10] A conceptual diagram of how the electric field spreads on the reflector after radio waves have passed through the phase adjustment plate. [Figure 11] 10 is a graph showing the integral power value and half-power diameter for each distance from the phase adjustment plate. [Figure 12] A graph showing the ratio (P×S) / (P0×S0) of the product of the integrated power value on the reflector and the area of ​​the half-power plane on the reflector when there is a phase adjustment plate to the product of the integrated power value on the reflector and the area of ​​the half-power plane on the reflector when there is no phase adjustment plate, for each distance from the phase adjustment plate. [Figure 13] A table showing the theoretical formula for the power reflected from a reflector. [Figure 14] FIG. 10 is a diagram of a calculation model for simulating an electric field spreading from a reflector of the present invention. [Figure 15] A radar chart showing the electric field strength within a radius of 1 m around a reflector when a reflector is placed at the focus of the phase adjustment plate in the calculation model of Figure 14. [Figure 16] A radar chart showing the electric field strength within a 1m radius around the reflector when the reflector is placed at a position shifted from the focus of the phase adjustment plate in the calculation model of Figure 14. [Figure 17] FIG. 10 is a diagram of a calculation model for simulating an electric field spreading from a reflector without providing a phase adjustment plate in a comparative example. [Figure 18] 18 is a radar chart showing the electric field intensity within a radius of 1 m around the reflector of the comparative example model of FIG. 17. [Figure 19] Graph showing a comparison of the electric field strength within a radius of 1 m around the reflectors in Figures 15, 16, and 18. [Figure 20] A table showing the electric field amplification, power integral value, power half-value diameter, and area ratio for a radius of 1 m around the reflector in the calculation model. [Figure 21] FIG. 10 is a diagram showing a calculation model for simulating an electric field spreading from the focal position of a phase adjustment plate in a comparative example without providing a reflector. [Figure 22] 22 is a radar chart showing the electric field intensity within a radius of 1 m around the focal position of the phase adjustment plate in the comparative example model of FIG. 21. [Figure 23] FIG. 5 is a schematic diagram of a radio wave control system according to a second embodiment of the present invention. [Figure 24] FIG. 10 is a schematic top view of a radio wave control system according to a third embodiment of the present invention. [Figure 25] FIG. 11 is a schematic side view of a radio wave control system according to a modified example of the third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that for ease of understanding, the scale of each component in the drawings may differ from the actual scale. Directions such as parallel, right-angled, orthogonal, horizontal, vertical, up-down, left-right, and the like are permissible to the extent that they do not impair the functions and effects of the embodiments. The shape of the corners is not limited to right angles, and may be rounded in an arched shape. Parallel, right-angled, orthogonal, horizontal, and vertical may include approximately parallel, approximately right-angled, approximately orthogonal, approximately horizontal, and approximately vertical.

[0011] In this specification, a three-dimensional Cartesian coordinate system with three axes (X-axis, Y-axis, and Z-axis) is used, with the width direction of the wall being the X-axis, the height direction of the wall being the Z-axis, and the thickness direction of the wall being the Y-axis. The direction from the bottom to the top of the wall is the +Z-axis, and the opposite direction is the -Z-axis. The direction from outdoors to indoors is the +Y-axis, and the opposite direction is the -Y-axis. In the following description, the +Z-axis direction may be referred to as up and the -Z-axis direction may be referred to as down, and the +Y-axis direction may be referred to as the indoor side and the -Y-axis direction may be referred to as the indoor side.

[0012] The X-axis, Y-axis, and Z-axis directions represent directions parallel to the X-axis, Y-axis, and Z-axis, respectively. The X-axis, Y-axis, and Z-axis directions are perpendicular to each other. The XY plane, YZ plane, and ZX plane represent imaginary planes parallel to the X-axis and Y-axis directions, imaginary planes parallel to the Y-axis and Z-axis directions, and imaginary planes parallel to the Z-axis and X-axis directions, respectively.

[0013] In the following explanation, "millimeter waves" or "millimeter wave band" refers to the frequency band of 30 GHz to 300 GHz as well as the quasi-millimeter wave band of 24 GHz to 30 GHz. "Radio waves" are a type of electromagnetic wave, and generally, electromagnetic waves below 3 THz are called radio waves. In the following, electromagnetic waves emitted from outdoor base stations or relay stations will be called "radio waves," and electromagnetic waves in general will be called "electromagnetic waves." In the figures, the same elements will be given the same symbols, and duplicate explanations may be omitted.

[0014] First Embodiment 1 is a schematic top view of a radio wave control system 1 according to a first embodiment. The radio wave control system 1 of the present invention is a wireless communication system for improving the communication environment for wireless communication.

[0015] The radio wave control system 1 according to the first embodiment includes a phase adjustment plate 10 and a reflector 20. In this embodiment, the phase adjustment plate 10 is provided on a glass plate 30. The glass plate 30 on which the phase adjustment plate 10 is arranged is not limited to the window glass of the building BD shown in FIG. 1 , but may also be the roof of a shelter at a bus stop or station platform, the rear glass of a car, etc.

[0016] In this embodiment, the reflector 20 is positioned on the wall 40 so that the main surface faces the phase adjustment plate 10, at a position where the radio waves transmitted through the phase adjustment plate 10 are irradiated. The wall 40 on which the phase adjustment plate 10 is placed is not limited to the wall of the building BD, and may be the wall of a shelter at a bus stop or station platform, the wall of a vehicle body, or the like, as long as it is within the range where the radio waves transmitted through the phase adjustment plate 10 can reach.

[0017] Generally, the walls of the building BD act as a shield against millimeter-wave radio waves, blocking them or significantly attenuating them. Therefore, radio waves emitted from an outdoor base station enter indoors through the windowpane, not the wall. Since radio waves that pass through the windowpane 30 continue traveling in a straight line, areas inside the building BD other than within the line of sight (LOS) become blind zones with poor communication environments, making it difficult to receive radio waves.

[0018] Therefore, in the radio wave control system of this embodiment, as shown in FIG. 1, the phase adjustment plate 10 is installed on the indoor side of the glass plate 30 of the building BD, and the reflector 20 is placed inside the building.

[0019] With this configuration, the glass plate 30 on which the phase adjustment plate 10 is installed focuses radio waves, which are emitted from, for example, an outdoor base station BS (see FIG. 3) and incident on the glass plate 30, at a predetermined focal point F. In this embodiment, by placing the reflector 20 at a predetermined position inside the building BD at or near the focal point F, the reflector 20 can reflect radio waves with high energy density in a desired direction. This makes it possible to improve the communication environment in areas indoors where the reflected radio waves reach.

[0020] The phase adjusting plate 10 provided on the glass plate 30 is, for example, a Fresnel lens (FZPL), a dielectric lens, or a frequency selective plate.

[0021] The reflector 20 is, for example, a reflector whose reflection angle can be electrically changed, such as an active reflector, a RIS (Reconfigurable Intelligent Surface), or a metasurface reflector. The reflector 20 reflects radio waves in a desired direction other than specular reflection. Alternatively, the reflector 20 may be a reflector that reflects radio waves at a fixed angle other than specular reflection.

[0022] Here, the radio waves controlled by the radio wave control system 1 are preferably in the millimeter wave band, such as that of a fifth-generation mobile communication system (5G), or in the 1 to 30 GHz range, including Sub-6. Alternatively, the controlled radio waves may be Long Term Evolution (LTE), LTE-Advanced (LTE-A), Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark), IEEE 802.20, Ultra-Wideband (UWB), Bluetooth (registered trademark), or Low Power Wide Area (LPWA). Any communication system, such as other extended communication systems, may also be used. Note that as the frequency increases, propagation loss due to reflection and diffraction increases, making such blind zones more likely to occur. Therefore, the radio wave control system 1 of the present invention is more suitable for communications using relatively high frequencies.

[0023] (Phase adjustment plate) 2 is a schematic diagram of a glass plate 300 with a phase adjusting plate according to the first embodiment. The phase adjusting plate 10 is attached to a glass substrate 301 of a glass plate 30 by an adhesive layer 302.

[0024] The phase adjustment plate 10 has a base 11 having a first main surface 111 and a second main surface 112 facing each other, and a conductor pattern 12 provided on the first main surface 111 of the base 11. Here, the "main surface" is a surface that is perpendicular to the thickness direction of the base 11. The base 11 transmits electromagnetic waves incident from the second main surface 112 to the first main surface 111.

[0025] The base 11 is formed of any material that is transparent to electromagnetic waves at the operating frequency of the radio wave control system 1 and that can support the conductor pattern 12. "Transparent" means that the transmittance is 60% or more, preferably 70% or more, more preferably 80% or more, and even more preferably 90% or more. As an example, a resin base material is used for the base 11. Examples of resin materials that satisfy the above conditions include acrylic resins such as polymethyl methacrylate, cycloolefin resins, and polycarbonate resins.

[0026] From the viewpoint of application to the glass plate 30, the conductor pattern 12 is preferably formed of a transparent conductive film such as zinc oxide (ZnO), tin oxide (SnO2), tin-doped indium oxide (ITO), indium oxide-tin oxide (IZO), etc. However, depending on the application, it may be formed of a metal thin film such as copper, nickel, gold, etc. In the case of a metal thin film, it is preferable to form it in a mesh shape from the viewpoint of visibility.

[0027] The glass substrate 301 may be made of commonly available glass, such as soda-lime glass, alkali-free glass, aluminosilicate glass, Pyrex (registered trademark) glass, or quartz glass. The adhesive layer 302 is formed of any adhesive material that is transparent to electromagnetic waves at the operating frequency of the radio wave control system 1 and that can bond the glass substrate 301 and the substrate 11 of the phase adjustment plate 10. The "transparent" meaning of the adhesive layer 302 is the same as the "transparent" meaning of the substrate 11. When the glass plate 30 is used as window glass, the entire glass plate 300 with a phase adjustment plate may be transparent to visible light.

[0028] 1 and 2 show a configuration in which the phase adjustment plate 10 is formed separately from the glass plate and attached to the glass base 301 with the adhesive layer 302, but the phase adjustment plate 10 and the glass plate 30 may be integrated into a phase adjustment plate-mounted glass plate. Alternatively, after the base 11 is attached to the glass base 301 with the adhesive layer 302, a conductive film may be formed on the first main surface 111 of the base 11, and the conductor pattern 12 may be formed by photolithography and etching.

[0029] The conductor pattern 12 formed on the first main surface 111 of the substrate 11 forms a metasurface. "Metasurface" refers to an artificial surface that controls the transmission and reflection characteristics of incident electromagnetic waves. By controlling at least one of the phase and amplitude of the electromagnetic waves incident on the conductor pattern, it is possible to realize optical properties that do not exist in nature. The conductor pattern 12 can transmit, reflect, or focus (concentrate) the incident electromagnetic waves in a desired direction.

[0030] 3 is a top view illustrating the operating principle of the radio wave control system 1. A glass plate 30 is fitted into a wall 40. The height direction of the wall 40 is defined as the Z direction, the direction from the wall 40 toward the indoor IN is defined as the Y direction, and the direction perpendicular to the Z direction and the Y direction is defined as the X direction. The glass plate 30 is positioned so that the conductor pattern 12 faces the indoor IN.

[0031] Therefore, in this embodiment, as shown in Figures 1 and 3, the phase adjustment plate 10 and the reflector 20 are installed facing each other, and the main surface of the phase adjustment plate 10 and the main surface of the reflector 20 are in a parallel positional relationship.

[0032] Radio waves emitted from an outdoor base station BS are incident on the glass plate 30, for example, from a direction perpendicular to the glass plate 30. The incident radio waves pass through the glass plate 30 and the phase adjustment plate 10, and are caused to form a focal point F at a position a distance df from the first main surface 111 by the conductor pattern 12 on the first main surface 111 of the phase adjustment plate 10. By disposing a reflector 20 at the position of such focal point F or at a position near the focal point F and a distance dy from the first main surface 111, the radio waves that have been focused and have a high energy density can be reflected by the reflector.

[0033] In this embodiment, the height from the ground of the glass plate 30 of the building BD where the phase adjustment plate 10 is provided is preferably 1 to 14 m, and particularly preferably 2 to 10 m, in terms of radio wave efficiency.

[0034] Furthermore, in this embodiment, on the wall 40 of the building BD, the reflector 20 is installed indoors in the same room as the room in which the phase adjustment plate 10 is installed, and the height of the reflector 20 from the ground is preferably 1 to 14 m, and particularly preferably 2 to 10 m, in terms of radio wave efficiency.

[0035] 4 shows a light-collecting pattern 13 included in the conductor pattern 12 of the phase adjusting plate 10. The light-collecting pattern 13 is an example of a second pattern that forms the conductor pattern 12.

[0036] The conductor pattern may have a further periodic pattern (unit cell pattern) inside. The pattern size is determined according to the target frequency. By repeating the unit cell pattern to create a periodic structure, it acts as a resonator that resonates with electromagnetic waves of the target frequency. The shape of the periodic pattern can be rectangular, cross, ring, etc.

[0037] The light-collecting pattern 13 shown in FIG. 4 is a Fresnel lens pattern formed of concentric circles 131-1 to 131-n around a center C1. Because the cross-sectional views in FIGS. 2 and 3 are schematic, the conductor pattern 12 on the substrate 11 is shown continuously. However, in detail, the Fresnel lens pattern configuration periodically arranges regions that transmit radio waves and conductor regions that reflect (block) radio waves according to the wavelength of the radio waves to be focused. Specifically, the light-collecting pattern 13 has circular shielding portions (also called conductor portions or reflective portions) 131-1 to 131-n and circular transmitting portions arranged concentrically around the center C1, alternating. The concentric circular shielding portions 131-1 to 131-n, which are the conductor pattern 12 made of a transparent conductive film, have narrower line widths of the concentric circles 131 as they move away from the center C1, and the spacing between adjacent concentric circles 131 also narrows. In FIG. 4, concentric circles 131-1 to 131-n, which are planar patterns, form lenses that are convex in the direction of propagation of electromagnetic waves.

[0038] If the radius of the n-th concentric circle 131-n is rn, the focal length of the light-condensing pattern 13 is f, and the wavelength of the incident electromagnetic wave is λ, then:

[0039]

number

[0040]

number

[0041] When the conductor pattern 12 shown in FIG. 4 is used, the distance df from the phase adjustment plate 10 in FIG. 3 to the focal point F is approximately 1000 mm. Here, the word "approximately" is intended to allow for an error of ± several mm due to manufacturing errors, measurement errors, etc. In the following description, even if a numerical value is not accompanied by "approximately," this does not exclude the allowable error.

[0042] The phase adjustment plate 10 configured in this manner is preferably large enough to include Fresnel zones of fourth order or higher (n≧2), and more preferably large enough to include Fresnel zones of sixth order or higher (n≧3).

[0043] (Modification of Phase Adjustment Plate) While FIG. 4 shows an example in which a Fresnel lens is configured by providing a planar conductor pattern 12 as the phase adjustment plate 10, a phase compensation Fresnel lens may also be used as the phase adjustment plate 10. For example, the transmission phase may be adjusted by varying the thickness of the substrate at the concentric circle 131. Specifically, the desired effect can be achieved by increasing the thickness of the substrate at the concentric circle 131 by λg / 2, where λg is the wavelength of the radio wave in the substrate. Alternatively, the transmission phase may be adjusted by varying the dielectric constant of the substrate at the concentric circle 131, and the dielectric constant and thickness may be continuously distributed.

[0044] In the present invention, by placing a reflector 20 at or near the focal point F of the phase adjustment plate 10, the radio waves that have been condensed and have a high energy density can be reflected by the reflector 20, thereby enabling an efficient expansion of the power receiving area indoors.

[0045] Here, a method for adjusting the reflection angle when the reflector 20 is, as an example, a directivity control array that can adjust the beam directivity, called a RIS (Reconfigurable Intelligent Surface), will be described with reference to Figures 5 and 6.

[0046] Fig. 5 is a conceptual diagram of the reflection angle when the reflector of the present invention is a reflectarray. Fig. 6 is an explanatory diagram of the mechanism for adjusting the reflection angle in each cell of the reflectarray to which radio waves that have passed through the phase adjustment plate are incident.

[0047] In the reflector 20 configured as a reflectarray shown in Figure 5, the phase of the radio waves is changed when they are reflected at each location, i.e., for each cell 21 called a unit cell, and by arranging these cells 21 in an array, the direction of the reflected radio waves, beam B, is adjusted.

[0048] More specifically, each cell 21 is provided with a reflecting element (not shown) capable of adjusting the reflection phase. Because radio waves are incident obliquely on the outer surface of the cell 21, the phase difference of the radio waves reflected by the reflecting element is set for each location, taking into account the inter-cell distance d (see FIG. 6), thereby changing the reflection phase in one cell 21. By making this different for each location in multiple cells 21, it is possible to change the overall reflection direction.

[0049] 5 shows an example in which the reflector adjusts the reflection angle for polarized waves incident in one direction from one direction, but the reflector in the radio wave control system of the present invention can function as an RIS that can adjust the reflection angle for polarized waves in two directions, vertical polarization and horizontal polarization. Alternatively, the reflector 20 of the present invention may be able to adjust the reflection angle for one-sided polarization (vertical polarization, horizontal polarization, left-handed circular polarization, right-handed circular polarization).

[0050] Here, in the configuration of the present invention, the radio waves incident on the reflector 20 are radio waves collected by the phase adjustment plate 10, and therefore the radio waves incident on the reflector 20 are angled so as to be concentrated toward the focal point F, and the radio waves are not plane waves, but have different incident angles and radio wave phases for each position of the cell 21.

[0051] For example, as shown in FIG. 6, when radio waves incident along the x-axis and transmitted through the phase adjustment plate 10 are reflected along the x-axis, the reflection direction is changed by adding a phase at each location x of each cell 21.

[0052] Here, when the phase φn of the incident wave for the nth element is based on the first incident wave, if the incident wave is a spherical wave generated from a point-like wave source, it can be expressed by the following equation (3).

[0053]

number

[0054]

number

[0055]

number

[0056] Although the case of a point wave source has been described above, when the incident wave is emitted from a wave source of finite size as in this embodiment, the phase value obtained by integrating the wave on the phase adjustment plate with each point on the phase adjustment plate regarded as a point wave source can be used as φn. In this way, in the reflector 20 of the present invention, the reflection angle is set for each position of the multiple cells 21, taking into account the incident angles with different phases.

[0057] In this way, the radio wave control system 1 of the present invention can change the direction of the beam of radio waves emitted from a 5G base station, etc., and direct the beam in various directions or in any desired direction, or can create multiple beams.

[0058] In FIG. 6, we have described the case where a wave incident along the x-axis is reflected along the x-axis, but the reflector 20 of the present invention also functions as a reflector that can set the reflection angle to an angle other than specular reflection when the wave is incident along the y-axis or when the wave is incident and reflected obliquely with respect to the x-axis and y-axis.

[0059] The RIS constituting the reflector 20 included in the radio wave control system 1 of the present invention may be a digital RIS that varies the phase difference at discrete values ​​(for example, two values), or an analog RIS that varies the phase difference continuously. The RIS may be capable of electrically controlling the reflection direction, or may reflect light with the reflection direction fixed in a predetermined direction.

[0060] The size of the reflector 20 of the present invention configured in this manner is preferably such that, if it is rectangular, one side is 10λ or more and 40λ or less, where λ is the wavelength of radio waves in the air. Also, if the reflector 20 is circular, the diameter is preferably 10λ or more and 50λ or less.

[0061] FIG. 7 is a schematic block diagram of a radio wave control system 1 according to one embodiment of the present invention.

[0062] A control unit 50 is connected to the reflector 20 of the present invention as shown in Fig. 7. The control unit 50 of the present invention is realized by, for example, a microcomputer.

[0063] The control unit 50 receives input of the incident wave source position (including the direction of arrival of the plane wave by setting it at infinity) and reflection direction instructions (directivity instructions) from the outside, and controls the reflection angle of each of the multiple cells 21 of the reflector 20. In this case, the control unit 50 adjusts the reflection angle while adjusting the phase of the incident radio waves using the radio waves collected by the phase adjustment plate 10, as shown in Figures 5 and 6.

[0064] The control unit 50 may be placed on the wall 40 near the reflector 20, or may be placed a little distance away from the reflector 20, for example, on the ceiling or floor. External input to the control unit 50 is input from, for example, a management computer (not shown) that manages the building BD or a user terminal U1. The control unit 50 operates based on a power supply voltage generated by a power supply generation unit (not shown).

[0065] In this embodiment, a phase adjustment plate 10 installed on a windowpane concentrates radio waves emitted from, for example, an outdoor base station BS and incident on a glass plate 30 at a predetermined indoor focal point F. Then, a reflector 20 placed inside a building BD at or within a predetermined range near focal point F redirects the concentrated high-energy-density radio waves to a specific direction as beam B or to form multiple beams, thereby delivering the radio waves to blind zones. This eliminates blind zones for radio waves indoors and improves radio wave strength over a wide area, allowing an indoor user terminal U1 to communicate with an outdoor user terminal and obtain website and web page information on the Internet.

[0066] 7, for example, radio waves transmitted from an outdoor user terminal or website or web page information on the Internet arrive at the base station BS and can be received by a user terminal U1 indoors that was originally located in a blind zone via the phase adjustment plate 10 and reflector 20 of the radio wave control system 1. Also, radio waves transmitted from a user terminal U1 indoors that was originally located in a blind zone can be made to arrive at the base station BS via the reflector 20 and phase adjustment plate 10 of the radio wave control system 1 and can be received by a user terminal outdoors.

[0067] Although FIG. 7 shows an example in which a base station is installed outdoors, the installed base station may include a wireless relay station that retransmits radio waves.

[0068] (Example) The inventors created a model (computational model) that can calculate the electric field strength and phase for each distance from the phase adjustment plate, and the electric field on the reflector, and simulated and verified the electric field distribution.

[0069] Example 1 In this example, the electric field strength of radio waves transmitted through the phase adjusting plate at each distance was simulated using the calculation model of Fig. 8. Fig. 8 is a diagram of the calculation model for simulating the electric field strength of radio waves transmitted through the phase adjusting plate 10.

[0070] In this calculation model, the phase adjusting plate 10 is a Fresnel lens on which the conductor pattern 12 shown in Fig. 4 is formed, and a lens with a Fresnel order of 6 is used. In this example, the focal point F0 of the phase adjusting plate 10 is located at a distance df of 1000 mm from the lens formed by the conductor pattern 12 of the phase adjusting plate 10.

[0071] In this calculation model, no reflector was placed when simulating Figures 9A and 9B, but a reflector 20 was placed when simulating Figures 10A to 10D. In this case, the reflector 20 was a RIS, and was placed in front of the phase adjusting plate 10 so that the central axis of the phase adjusting plate 10 and the central axis of the reflector 20 coincided, and the distance dy of the reflector 20 from the phase adjusting plate 10 was set to 1300 mm.

[0072] In addition, in this calculation model, the phase adjustment plate 10 and the reflector 20 are not attached to a window or a wall, but are installed independently.

[0073] A plane wave was made incident on the second main surface 112 side of the phase adjusting plate 10, and the electric field after the plane wave passed through the phase adjusting plate 10 was simulated.

[0074] Figure 9A is a diagram showing the electric field strength of radio waves transmitted through the phase adjustment plate 10 for each distance from the phase adjustment plate 10, and Figure 9B is a diagram showing the phase of radio waves transmitted through the phase adjustment plate 10 for each distance from the phase adjustment plate 10.

[0075] 10A to 10D are conceptual diagrams showing how the electric field on reflector 20 spreads when radio waves have passed through phase adjustment plate 10. Fig. 10A is a conceptual diagram showing how the electric field on reflector 20 spreads when reflector 20 is at position a of focal point F. Figs. 10B, 10C, and 10D are conceptual diagrams showing how the electric field on reflector 20 spreads when reflector 20 is at a position other than the focal point.

[0076] 9A shows the electric field strength (radio wave strength) of radio waves transmitted through the phase adjusting plate 10, i.e., the strength of the electric field amplitude. As shown in FIG. 9A, the electric field strength is strongest at the focal point F indicated by line a. Here, in this specification, "focal point" means "the range where the electric field strength is 80% or more of the maximum value (peak) on the axis (central axis, optical axis) passing through the center of the phase adjusting plate and the focal point." Therefore, positions other than the focal point refer to the range where the electric field strength on the central axis is less than 80% of the maximum value of the electric field strength.

[0077] 10A to 10D, in the spread of the electric field on the reflector 20, the colored areas where the electric field amplitude is strong indicate regions where the electric field amplitude is equal to or greater than half of the maximum power, and the uncolored areas where the electric field amplitude is weak indicate regions where the electric field amplitude is less than half of the maximum power.

[0078] Here, the electric field strength that has passed through phase adjustment plate 10 is strongest at focal point F, but as shown in Fig. 9A, at focal point F, the electric field strength rapidly weakens as it moves outward in the X and Z directions away from the central axis on a plane perpendicular to the central axis. Therefore, when reflector 20 of a predetermined size is placed at focal position a in Fig. 9A, the irradiation range of the radio waves relative to reflector 20 becomes smaller as shown in Fig. 10A.

[0079] Furthermore, the maximum intensity of the electric field that passes through phase adjustment plate 10 decreases slightly as the distance from focal point F increases, but the weakening of the electric field intensity also decreases as the distance from the central axis increases in the X and Z directions. Therefore, when reflector 20 of a given size is placed at a position slightly shifted from the focal point, as shown in b of Fig. 9A, the irradiation range of reflector 20 becomes larger than that of Fig. 10A, as shown in Fig. 10B. In Fig. 10B, when the power distribution of the radio waves on reflector 20 is viewed, the region where the power is equal to or greater than half the maximum power occupies a wide area, and is irradiated continuously, i.e., in a single-connected manner, without any holes. Therefore, the state shown in Fig. 10B results in a good electric field spread on reflector 20.

[0080] Furthermore, as the distance from the focal point F increases, the electric field strength passing through the phase adjustment plate 10 weakens near the central axis and increases on the outer edges away from the axis in the X and Z directions. Therefore, when a reflector 20 of a given size is placed at the position shown in c in Fig. 9A, the radio wave irradiation range itself on the reflector 20 is large, but the electric field strength is weak in the center, less than half the maximum, as shown in Fig. 10C. Therefore, when the power distribution of the radio waves on this reflector 20 is viewed, holes are present in the areas where the maximum power is more than half the maximum power, and the surface is discontinuous.

[0081] Furthermore, at positions further away from the focal point F and closer to the phase adjusting plate 10, the electric field strength repeatedly increases and decreases as it moves outward in the X and Z directions from the axial direction, because the properties of the radio waves transmitted concentrically remain due to the lens effect of the Fresnel zones in the Fresnel lens. Therefore, when a reflector 20 of a given size is placed at the position shown in d in Fig. 9A, areas of strong and weak electric field strength alternate concentrically on the reflector 20, as shown in Fig. 10D. As a result, when the power distribution of the radio waves on this reflector 20 is viewed, in areas where the power is equal to or greater than half of the maximum power, concentric holes appear, and the surface is discontinuous.

[0082] 6, the reflector 20 included in the radio wave control system 1 of the present invention is a reflectarray made up of a plurality of cells 21, and the received power is proportional to the area. The degree of convergence of the radio waves radiated from the reflector 20 is also proportional to the area, and the received power is proportional to the square of the area A of the reflector 20. Therefore, the larger the size of the reflector 20, the better the performance.

[0083] At the position of focal point F, as in position a in Figure 9A, the electric field strength is strong, including the peak with the greatest strength (the white area in the figure), but the area irradiated by the radio waves is small relative to the reflector, as in Figure 10A. Therefore, if a large reflector is installed, the radio waves will not be reflected outside the reflection. Therefore, depending on the size of the reflector, installing a reflector other than at the focal point can improve reflection efficiency.

[0084] For example, let's say each cell of the reflector can efficiently reflect radio waves at more than half the maximum power that passes through the phase adjustment plate. When viewing the power distribution of radio waves on the reflector, with respect to the power that passes through the phase adjustment plate in relation to the position of the phase adjustment plate and the reflector, it is preferable that the area of ​​the region with a field strength of more than half the maximum power occupies more than 50% of the reflector's area. It is also more preferable that the power of the radio waves incident on the reflector is more than half the maximum power and has a nearly constant amplitude. For example, in the example shown in FIG. 10B, the colored irradiated area with a field strength of more than half the maximum power accounts for 63% of the entire surface of the reflector 20.

[0085] On the other hand, since the wider the electric field and the closer the reflected electric field strength is to the peak, the better the reflected power of the radio waves reflected by the reflector, it is preferable to install the reflector at a position other than the focus but close to the focus. Here, the focus refers to the area on the central axis where the electric field strength of the radio waves transmitted through the phase adjustment plate 10 is 80% or more of the maximum value, as shown in FIG. 9A. Therefore, installing the reflector 20 at a position other than the focus means installing the reflector 20 in a range where the electric field strength on the central axis is less than 80% of the maximum electric field strength.

[0086] Furthermore, in the reflector 20 configured as a reflectarray, cells that receive radio waves reflect the radio waves, while cells that do not receive radio waves do not reflect the radio waves. Therefore, it is desirable that the strength of the radio waves incident on the reflector 20 does not have any weak spots, and that the strength of the incident radio waves is maintained at a certain level or higher. In other words, it is preferable that the area on the reflector 20 where the power is at least half of the maximum power is continuous and simply connected, without any holes.

[0087] Furthermore, referring to FIG. 9B, it can be seen that the phase of the radio wave that has passed through phase adjustment plate 10 has little phase distortion at focal point F indicated by line a, but the further away from the focal point, the more phase distortion occurs.

[0088] Generally, a reflector performs better when the phase of the incident radio waves is constant. However, when the reflector 20 of the present invention is a directivity control array such as a RIS, the reflection phase is set taking into account the phase difference of the incident radio waves, as explained in Fig. 6, so the reflection angle can be appropriately adjusted even if the reflector 20 is placed not at the focal point but at a position shifted from the focal point where the phase is slightly distorted.

[0089] Here, based on the electric field intensity simulated in FIG. 9A, the half-power diameter, the power integral ratio, and the area ratio on the reflector 20 for each distance from the phase adjusting plate 10 were calculated.

[0090] The half-power diameter on the reflector 20 corresponds to the diameter of the circle indicated by the arrow in the examples of FIGS. 10A and 10B, while in the examples of FIGS. 10C and 10D, the electric field amplitude is weak at the center, so the half-power diameter is 0.

[0091] 11 is a graph showing the integral power value and the half-power diameter. In this example, the half-power diameter was calculated using a 100 mm square reflector in order to compare the diameter within the reflector.

[0092] In the present invention, it is desirable to arrange the reflector in the radio wave control system so that the electric field strength is stronger when the reflector is provided than when the reflector is not provided. Therefore, it is necessary to arrange the reflector in a position where the integrated power value of the radio wave on the reflector is larger than when the phase shifting plate is not provided. In other words, the reflector is arranged in a position where the amplification degree of the amplitude of the radio wave that has passed through the phase shifting plate is larger than 0 dB (antilogarithm 1). Therefore, in the example of FIG. 11, it is preferable to arrange the reflector at a distance of 0 to 1500 mm from the phase shifting plate 10.

[0093] Furthermore, when looking at the power distribution of radio waves on the reflector, it is more preferable that the half-power diameter, which corresponds to the outline of the area where the power is equal to or greater than half of the maximum power, is equal to or greater than 50% of the area of ​​the reflector. Therefore, in the example of Fig. 11, it is more preferable that the reflector be provided at a distance of 820 to 850 mm or 1230 to 1310 mm from the phase adjustment plate 10.

[0094] The optimum position of such a reflector can be expressed mathematically as follows: the absolute value of the electric field strength of the radio waves that have passed through the phase adjustment plate is averaged on the reflector as Ave[|E|], and the electric field strength of the radio waves when the reflector is placed at the focal point is averaged on the reflector as Ave[|E f |], Ave[|E|] / Ave[|E f It is preferable to install it in a position that satisfies |]>1.

[0095] Ave[|E|] is expressed by the following formula (6): In formula (6), S represents the area of ​​the reflector, and E represents the electric field strength of the radio wave that has passed through the phase adjustment plate.

[0096]

number

[0097] To find this, let P be the value obtained by integrating the power of radio waves on the reflector when they pass through the phase adjustment plate, let S be the area of ​​the half-power surface on the reflector, and let P0 and S0 be the values ​​of P and S when there is no phase adjustment plate, respectively.The positions that satisfy (P×S) / (P0×S0)>1 are candidates.

[0098] Fig. 12 shows the ratio (P x S) / (P0 x S0) of the product of the integrated power value on the reflector and the area of ​​the half-power plane on the reflector when there is a phase adjustment plate to the product of the integrated power value on the reflector and the area of ​​the half-power plane on the reflector when there is no phase adjustment plate. Here, the irradiation area ratio is calculated by the area of ​​the half-power region / the area of ​​the reflector (S / S0), so the waveform in Fig. 12 shows a similar trend to the half-power diameter in Fig. 11.

[0099] The amplification factor is calculated using the table in Figure 13. The information calculated from the electric field strength relative to the reflector is summarized in the table in Figure 13. Figure 13 is a table showing the formula for calculating the electric field strength reflected from the reflector. In Figure 13, k is the electric field amplification factor due to the phase adjustment plate, and ζ is the vacuum impedance (120πΩ).

[0100] In the present invention, as explained in Figures 10A to 10D, in order to increase the efficiency on the reflector, it is preferable to place it in a position where the area of ​​the half-value plane, which is the region where the power distribution of radio waves on the reflector is more than half of the maximum power, is more than 50% of the area of ​​the reflector, as shown in Figure 10B.

[0101] Therefore, in the example of the graph showing the amplification degree x irradiation area ratio in FIG. 12, it is more preferable to provide the reflector 20 at a distance from the phase adjusting plate 10 of 820 to 850 mm or 1230 to 1310 mm.

[0102] In the above-mentioned preferred range, 850 mm and 1230 mm on the side closer to the focal point are approximately 200 mm, i.e., approximately 20% to 30% of the focal length, away from the position of the focal point F. Therefore, in this embodiment, in which a phase adjusting plate 10 with a Fresnel order of 6 is used, it is preferred that the reflecting plate 20 be positioned at a distance of 20% or more of the focal length from the focal point of the phase adjusting plate 10.

[0103] The above-mentioned optimum position of the reflector 20 relative to the phase adjustment plate 10 is the result when the Fresnel order is 6 or less. For example, when the Fresnel order is greater than 6 and less than or equal to 12, it is preferable that they are separated by 15% or more. When the Fresnel order is greater than 12 and less than or equal to 24, it is preferable that they are separated by 7% or more.

[0104] In this embodiment, the reflector is positioned away from the focal point as an example of arranging the reflector at a position where the area of ​​the region where the half-value of the maximum power is more than 50% of the area of ​​the reflector when looking at the power distribution of the radio waves on the reflector, so that the electric field strength becomes stronger when the reflector is provided compared to a configuration without the reflector. However, the method of placing the reflector so that the area where the half-value of the maximum power is more than 50% of the area of ​​the reflector is not limited to this method. For example, the phase adjustment plate may have multiple focal points, and the reflector may be placed at a position that includes the multiple focal points.

[0105] Example 2 In this example, the calculation model of FIG. 14 was used to simulate the field intensity of the electric field reflected from the reflector while changing the conditions.

[0106] 14 shows a calculation model used to simulate the electric field spreading from the reflector of the present invention. In this example, the phase adjustment plate 10 is a Fresnel lens, and the Fresnel order is set to 6. The reflector 20 is a RIS, and the target angle of the reflected radio wave is set to an azimuth angle of 30° and an elevation / depression angle of 0°, and the electric field strength of the plane wave incident on the phase adjustment plate 10 is set to 0 dBV / m.

[0107] Fig. 15 is a radar chart showing the electric field intensity at a radius of 1 m around the reflector when the reflector 20 is placed at the focal point of the phase adjusting plate 10 in the calculation model of Fig. 14. In Fig. 15, the simulation was performed with the distance between the phase adjusting plate 10 and the reflector 20 in the calculation model of Fig. 14 set to 1000 mm, which is the focal length. In this calculation, as shown in Fig. 15, the maximum value of the electric field intensity was at a position of 30°, in line with the target angle of 30°, and the maximum value was -2.0 dBV / m.

[0108] Figure 16 is a radar chart showing the electric field strength within a radius of 1 m around the reflector when the reflector is placed at a position offset from the focal point of the phase adjustment plate in the calculation model of Figure 14. In Figure 16, the simulation was performed with the distance between the phase adjustment plate 10 and the reflector 20 in the calculation model of Figure 14 set to 1300 mm, which is offset from the focal length. As shown in Figure 16, the maximum value of the electric field strength was at the 30° position, in line with the target angle of 30°, and the maximum value was +0.6 dBV / m.

[0109] FIG. 17 is a diagram of a calculation model for simulating an electric field spreading from a reflector without providing a phase adjustment plate in a comparative example.

[0110] Fig. 18 is a radar chart showing the electric field strength within a radius of 1 m around the reflector of the comparative example model of Fig. 17. As shown in Fig. 18, the maximum value of the electric field strength was at a position of 30°, in line with the target angle of 30°, and the maximum value was -2.9 dBV / m.

[0111] Fig. 19 is a graph showing the electric field intensity within a radius of 1 m around the reflectors of Fig. 15, Fig. 16, and Fig. 18. In Fig. 19, the solid line Plane wave shows the electric field intensity when no phase adjustment plate is provided (Fig. 17), the dashed line FZPL focal shows the electric field intensity when reflector 20 is placed at the focal point, and the dashed line FZPL non focal shows the waveform of the electric field intensity when reflector 20 is placed at a position away from the focal point.

[0112] 19, the maximum value of the electric field strength is higher with the phase adjustment plate than without it. Also, the peak of the electric field strength of the reflected radio waves is larger when the reflector 20 is placed at a position shifted from the focus of the phase adjustment plate 10 than when it is placed at the focus.

[0113] Figure 20 is a table showing the electric field amplification factor within a 1m radius of the reflector, the power integral value on the reflector, the half-power diameter, Ave[|E|] / Ave[|E0|] on the reflector, and the power integral value × irradiation area ratio (P × S) / (P0 × S0) in the measurement model.

[0114] In the table of Fig. 20, when comparing the electric field amplification degree within a 1 m radius of the reflector, the power integral value on the reflector, the half-power diameter, and Ave[|E|] / Ave[|E0|] with and without the phase shift plate 10, the case with the phase shift plate 10 is better than the case without it. In Fig. 20, the comparison values ​​are also listed, with the case with the phase shift plate set to 1.

[0115] Here, Ave[|E|] / Ave[|E0|] is a value that corresponds to the increase in field strength amplification from the value within a 1m radius of the reflector when there is no phase shift plate. For example, if there is a reflector 1.3m from the phase shift plate, there is a 3.5dB increase (+0.6dB-(-2.9dB)), and Ave[|E|] / Ave[|E0|] increases by 4.6dB. Also, if there is a reflector 1m from the phase shift plate, there is a 0.9dB increase (-2.0dB-(-2.9dB)), and Ave[|E|] / Ave[|E0|] increases by 1.6dB.

[0116] In addition, when comparing the electric field amplification degree within a 1 m radius of the reflector, the power integral value on the reflector, the half-power diameter, Ave[|E|] / Ave[|E0|], and the power integral value on the reflector x irradiation area ratio in the table of Figure 20 at different positions of the reflector 20, the results are better when the reflector 20 is not positioned at the focal point than when it is positioned at the focal point.

[0117] In addition, the power integral value on the reflector x irradiation area ratio and Ave[|E|] / Ave[|E0|] are both maximized when the field amplification at a radius of 1.3 m is maximized, that is, when the phase adjustment plate is placed 1.3 m away from the focus. Therefore, good characteristics can be obtained by installing the RIS based on these two indicators. Furthermore, Ave[|E|] / Ave[|E0|] shows a good correlation with the field amplification at a radius of 1 m. Therefore, more desirable characteristics can be obtained by using Ave[|E|] / Ave[|E0|] as an indicator.

[0118] Therefore, in this embodiment using a phase adjustment plate 10 with Fresnel order 6, it is preferable to place the reflector 20 at a position that is not the focal point of the phase adjustment plate 10 and that is at least 20% away from the focal length.

[0119] 20, (P×S) / (P0×S0) deteriorates at the focus, but this is because this parameter is a calculation formula for finding a suitable location other than the focus and cannot be applied at the focus. This (P×S) / (P0×S0) index can be calculated more easily than the index Ave[|E|] / Ave[|E0|], so it has the advantage of making it easier to determine a suitable location other than the focus.

[0120] FIG. 21 is a calculation model diagram for simulating an electric field spreading from the focal position of a phase adjustment plate in a comparative example in which no reflector is provided.

[0121] Fig. 22 is a radar chart showing the electric field intensity within a radius of 1 m around the focal position of the phase adjusting plate in the model of the comparative example in Fig. 21. As shown in Fig. 22, the maximum value of the electric field intensity is 12.9 dBV / m.

[0122] In the calculation model of FIG. 21, radio waves incident on the front of the phase shift plate 10 are not reflected into the room by the reflector 20, and therefore reach only the front of the phase shift plate 10. Therefore, comparing the electric field intensity in FIG. 22 with that in FIGS. 15 and 16, the maximum value of the electric field intensity in FIG. 22 is only in the direction directly in front of the phase shift plate, and the reflection angle shown in FIG. 22 is narrower than when there is a reflector. Therefore, when there is a reflector 20 in the direction of radio wave propagation from the phase shift plate 10, the receivable range within a 1-m radius is wider than when there is no reflector 20. Furthermore, although not shown, such a strong electric field intensity does not appear around the phase shift plate at distances other than 1 m. This is because the focal length of the phase shift plate is 1 m.

[0123] As shown in the waveforms of electric field strength in Figures 19 and 22, the radio wave control system of the present invention, which has both a phase shifting plate and a reflector, improves the electric field strength compared to the case of using only a phase shifting plate or a reflector. As a result, the radio wave control system of the present invention can collect power using the phase shifting plate and distribute radio waves efficiently in the desired direction using the reflector.

[0124] In this example, we also simulated the electric field strength for a measurement model equipped with an array antenna instead of a reflector at a distance of 1300 mm off the focus of the phase adjustment plate, but we were unable to obtain the same effect as with a reflector. In other words, no improvement was observed when the antenna was off the focus compared to when it was placed at the focus of the phase adjustment plate.

[0125] (Second embodiment) In the above first embodiment, an example was described in which the phase adjustment plate 10 is provided on the window glass and the reflector 20 is provided on the wall, but the radio wave control system of the present invention may also be configured such that the phase adjustment plate 10 and the reflector 20 are integrated and provided on the wall.

[0126] 23 is a schematic diagram of a radio wave control system according to a second embodiment of the present invention. In a radio wave control system 2 according to this embodiment, a phase adjustment plate 10A and a reflector 20A are provided in a single case 60. Although not shown, a control unit 50 is also housed in the case 60.

[0127] In the radio wave control system 2 of this embodiment, in order to house the components in a single case and make the system compact, it is preferable that the reflector 20A be located in a predetermined range near the focal point F of the phase adjustment plate 10A and closer to the phase adjustment plate 10A than the focal point.

[0128] In this embodiment, the case 60 is made of any material that is transparent to electromagnetic waves at the operating frequency of the radio wave control system 2. As an example, the case 60 is made of a resin material such as an acrylic resin such as polymethyl methacrylate, a cycloolefin resin, or a polycarbonate resin.

[0129] In this embodiment, the components are housed in one case 60, so the radio wave control system 2 is movable and the installation location can be changed.

[0130] Furthermore, the radio wave control system 2 in this embodiment may be installed outdoors or indoors.

[0131] For example, in areas with many high-rise buildings, blind zones where radio waves cannot reach properly are likely to occur. However, by installing the radio wave control system 2 according to the second embodiment outdoors, radio waves can be delivered to these blind zones outdoors, thereby contributing to reducing the number of blind zones outdoors.

[0132] On the other hand, when the radio wave control system 2 according to the second embodiment is installed indoors, there is no need to attach a phase adjustment plate to the window glass, and simply attaching the integrated radio wave control system to an indoor wall will deliver radio waves to blind areas indoors, thereby contributing to reducing blind areas indoors. In this case, it is preferable to attach the integrated radio wave control system 2 to a wall facing a window or opening.

[0133] 23 shows a configuration in which all of the components of the radio wave control system 2 are housed in the case 60, but as a modification of this embodiment, the back side of the case 60 may be open. In this configuration, when installing the radio wave control system 2, the reflector is attached directly to the wall. In this configuration, the opening on the back side of the case allows the thickness of the radio wave control system 2 to be made thinner.

[0134] (Third embodiment) In the first and second embodiments, the phase adjustment plate and the reflector are disposed opposite each other, but the phase adjustment plate and the reflector do not have to be disposed opposite each other.

[0135] 24 is a schematic top view of a radio wave control system 3 according to a third embodiment of the present invention. In this embodiment, the design of the phase adjustment plate is changed so that radio waves transmitted through the phase adjustment plate 10B are converged obliquely toward the adjacent wall 40B at an angle of 90° horizontally relative to the glass plate 30 of the window glass.

[0136] Therefore, the reflector 20B in this configuration is placed on a wall approximately perpendicular to the phase adjustment plate. In the radio wave control system of this embodiment, the reflector 20B is also placed at the focal point of the phase adjustment plate 10B or in a predetermined range close to the focal point, allowing the phase adjustment plate 10B to collect power and the reflector 20B to efficiently reflect radio waves in the desired direction. As a result, the phase adjustment plate 10B and the reflector 20B deliver radio waves to blind zones indoors, contributing to reducing blind zones indoors. In this embodiment, this type of installation enables flattening suitable for glass attachment and design.

[0137] 25 is a schematic side view of a radio wave control system according to a modification of the third embodiment of the present invention. In this modification, the design of the phase adjustment plate is changed so that radio waves transmitted through the phase adjustment plate 10C are focused obliquely toward the ceiling, which is adjacent to the glass plate 30 of the window glass at an angle of 90° in the vertical direction.

[0138] For this reason, the reflector 20C of this configuration is placed on the ceiling 70 at a substantially right angle to the phase adjusting plate 10C. In the radio wave control system of this embodiment, the reflector 20C is also placed at the focal point of the phase adjusting plate 10C or in a predetermined range close to the focal point, so that the phase adjusting plate 10C collects power and the reflector 20C efficiently distributes radio waves from above in the desired direction. As a result, the phase adjusting plate and reflected waves deliver radio waves to blind zones indoors, contributing to reducing blind zones indoors.

[0139] Although Figure 25 illustrates an example in which the reflector 20C is installed on the ceiling 70, the reflector may also be placed on the floor so that the radio waves that pass through the phase adjustment plate 10C are focused obliquely toward the floor adjacent to the glass plate 30 of the window glass at an angle of 90° in the vertical direction.

[0140] In the third embodiment shown in Figures 24 and 25, an example is shown in which the main surface of the phase adjustment plate and the main surface of the reflector are perpendicular to each other, but by adjusting the direction of the focus of the phase adjustment plate, the main surface of the phase adjustment plate and the main surface of the reflector may be positioned at an acute angle or an obtuse angle.

[0141] Furthermore, although not shown, as another variation of the third embodiment, as in the second embodiment, the phase adjustment plate and the reflector may be housed in the same case, and the main surface of the phase adjustment plate and the main surface of the reflector may be arranged so as to be perpendicular to each other or at an acute or obtuse angle, so that the phase adjustment plate collects power and the reflector reflects radio waves in the desired direction.

[0142] The above describes an exemplary embodiment of a radio wave control system of the present invention, but the present invention is not limited to the specifically disclosed embodiment, and various modifications and changes are possible without departing from the scope of the claims.

[0143] This international application claims priority based on Japanese Patent Application No. 2021-119125, filed on July 19, 2021, and the entire contents of No. 2021-119125 are incorporated herein by reference. [Explanation of symbols]

[0144] 1, 2, 3, 3C Radio Control System 10, 10A, 10B, 10C Phase adjustment plate 20, 20A, 20B, 20C reflector 30 Glass Plate (Window Glass) 40, 40A, 40B Wall 60 cases 70 Ceiling 111 First main surface of phase adjustment plate 112 Second main surface of phase adjustment plate Ave[|E|] The absolute value of the electric field strength of the radio wave that has passed through the phase adjustment plate, averaged over the reflector Ave[|E f |] The average value of the electric field strength of the radio wave on the reflector when the reflector is placed at the focus Ave[|E0|] The average value of the electric field strength of radio waves on the reflector when there is no phase adjustment plate P is the integrated value of the power of the radio wave that has passed through the phase adjustment plate on the reflector. S is the area of ​​the half-power surface on the reflector P0 is the integrated value of the radio wave power on the reflector when there is no phase adjustment plate. S0 Area of ​​half-power surface on the reflector without phase adjustment plate

Claims

1. a phase adjustment plate that transmits the radio wave from the second principal surface to the first principal surface and focuses the radio wave to a focal point on the optical axis within a range where the electric field intensity is 80% or more of the maximum value; a reflector disposed at a position where the radio wave transmitted through the phase adjustment plate is irradiated, The reflector is a reflector that reflects at an angle other than specular reflection. Radio wave control system.

2. The reflector is installed at a position where the integrated power value of the radio wave on the reflector becomes larger than when the phase adjustment plate is not present. The radio wave control system according to claim 1 .

3. When observing the power distribution of radio waves on the reflector, the area of ​​the region where the power is equal to or greater than half of the maximum power is equal to or greater than 50% of the area of ​​the reflector.

3. The radio wave control system according to claim 1 or 2.

4. the reflector is disposed at a position other than the focal point of the phase adjustment plate, The position other than the focal point is a position on the axis passing through the center of the phase adjustment plate and the focal point where the electric field intensity is less than 80% of the maximum value. The radio wave control system according to claim 1 .

5. The reflector is installed at a position that satisfies Ave[|E|] / Ave[|Ef|]>1, where Ave[|E|] is the absolute value of the electric field strength of the radio waves that have passed through the phase adjustment plate and averaged on the reflector, and Ave[|Ef|] is the value of the electric field strength of the radio waves that are averaged on the reflector when the reflector is placed at the focal point. The radio wave control system according to claim 1 .

6. The reflector is installed at a position that satisfies (P×S) / (P0×S0)>1, where P is the value obtained by integrating the power of the radio wave that has passed through the phase adjustment plate on the reflector, S is the area of ​​the half-power plane on the reflector, and P0 and S0 are the values ​​of P and S when the phase adjustment plate is not present. The radio wave control system according to claim 5 .

7. The reflector is disposed at a distance of 7% or more from the focal point of the phase adjusting plate. The radio wave control system according to claim 6.

8. In the region where the radio wave transmitted through the phase adjustment plate strikes the reflector, When observing the power distribution of radio waves on the reflector, the area where the power is equal to or greater than half of the maximum power is a continuous area without holes. The radio wave control system according to any one of claims 5 to 7.

9. The reflector is a reflector that can change the reflection phase in each location on the reflection surface. The radio wave control system according to claim 1 .

10. The reflecting angle of the reflector can be electrically changed The radio wave control system according to claim 1 .

11. The reflector is installed on a wall or ceiling. The radio wave control system according to claim 1 .

12. The phase adjustment plate and the reflector are provided in one case. The radio wave control system according to claim 1 .

13. If the wavelength of the irradiated radio waves in the air is λ, then The side of the reflector is 10λ or more and 40λ or less, or the diameter is 10λ or more and 50λ or less. The radio wave control system according to claim 1 .

14. The frequency band of the radio waves is 1 GHz to 300 GHz. The radio wave control system according to claim 1 .

15. A phase adjustment plate that transmits radio waves from the second principal surface to the first principal surface and focuses the radio waves to a focal point on the optical axis within a range where the electric field strength is 80% or more of the maximum value; a reflector disposed at a position where the radio wave transmitted through the phase adjustment plate is irradiated, The reflector is installed at a position where the integrated power value of the radio wave on the reflector becomes larger than when the phase adjustment plate is not present. Radio wave control system.

16. A phase adjustment plate that transmits radio waves from the second principal surface to the first principal surface and focuses the radio waves to a focal point on the optical axis within a range where the electric field strength is 80% or more of the maximum value; a reflector disposed at a position where the radio wave transmitted through the phase adjustment plate is irradiated, When observing the power distribution of radio waves on the reflector, the area of ​​the region where the power is equal to or greater than half of the maximum power is equal to or greater than 50% of the area of ​​the reflector. Radio wave control system.

17. A phase adjustment plate that transmits radio waves from the second principal surface to the first principal surface and focuses the radio waves to a focal point on the optical axis within a range where the electric field strength is 80% or more of the maximum value; a reflector disposed at a position where the radio wave transmitted through the phase adjustment plate is irradiated, The reflector is installed at a position that satisfies Ave[|E|] / Ave[|Ef|]>1, where Ave[|E|] is the absolute value of the electric field strength of the radio waves that have passed through the phase adjustment plate and averaged on the reflector, and Ave[|Ef|] is the value of the electric field strength of the radio waves that are averaged on the reflector when the reflector is placed at the focal point. Radio wave control system.

18. A phase adjustment plate that transmits radio waves from the second principal surface to the first principal surface and focuses the radio waves to a focal point on the optical axis within a range where the electric field strength is 80% or more of the maximum value; a reflector disposed at a position where the radio wave transmitted through the phase adjustment plate is irradiated, The reflector is a reflector that can change the reflection phase in each location on the reflection surface. Radio wave control system.

19. A phase adjustment plate that transmits radio waves from the second principal surface to the first principal surface and focuses them to a focal point on the optical axis within a range where the electric field strength is 80% or more of the maximum value; a reflector disposed at a position where the radio wave transmitted through the phase adjustment plate is irradiated, The reflecting angle of the reflector can be electrically changed Radio wave control system.

Images