Electromagnetic wave matching device, electromagnetic wave passing device, and wall

Abstract

To configure an electromagnetic wave matching device, an electromagnetic wave passing device, and a wall that can expand the communicable range within a building and maintain wireless communication at any location without adding any additional communication equipment.SOLUTION: An electromagnetic wave passing device 201 is arranged on a first surface S1 of a dielectric member such as a wall main body 1 having the first surface S1 and a second surface S2 facing each other, and an electromagnetic wave passing device 202 is arranged on the second surface S2. The electromagnetic wave passing device 201 includes a first resonant circuit, and the electromagnetic wave passing device 202 includes a second resonant circuit. The first resonant circuit and the second resonant circuit are electromagnetically coupled mainly via a magnetic field.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to walls of buildings such as apartment buildings and hotels, and more particularly to a wall surface electromagnetic wave matching device, an electromagnetic wave transmission device, and a wall. [Background technology]

[0002] A building is made up of structural members, which are the main structural members required to build it, and non-structural members, such as decorative materials, finishing materials, and interior materials, which are not the main structural members. For example, in apartment buildings and hotels, gypsum board (PB), lightweight aerated concrete (ALC), or concrete are used in some of the walls, ceilings, floors, etc.

[0003] Generally, wireless LANs within a building are not limited to use within a single room, but are used in a wide area separated by walls, ceilings, and floors.

[0004] However, when using a wireless LAN inside a building, reflection and absorption of wireless LAN radio waves by the building's structural and non-structural components often become a problem. Radio waves do not propagate in materials such as gypsum board (PB), lightweight aerated concrete (ALC), or concrete, as they do in free space. Instead, radio waves are reflected on the surfaces of these materials and absorbed (attenuated) within them. This results in increased insertion loss along the radio wave propagation path in the communication path.

[0005] Therefore, in general, the communication range is increased by increasing the number of access points to reduce the insertion loss of radio waves in each communication path. [Prior art documents] [Patent documents]

[0006] [Non-Patent Document 1] Nippon Electric Glass Co., Ltd., "Development of new product to expand 5G wireless communication area," [online], June 23, 2022, News Release, [Retrieved January 16, 2024], Internet〈URL: https: / / www.neg.co.jp / news / 20220623-5697.html〉 [Non-patent document 2] NTT Docomo and AGC, "NTT Docomo and AGC Conduct Demonstration Experiment of Transparent Metasurface Technology to Dynamically Control Transmission and Reflection of 28GHz Band 5G Radio Waves | IoT NEWS," [online], January 13, 2024, [Retrieved January 16, 2024], Internet〈URL: https: / / iotnews.jp / communication / 144891 / 〉 [Non-patent document 3] Fujitsu, "Poynting for Microwave Analysis Case Study: Analysis of Shielding Effect of Wireless LAN Band Using FSS (Frequency Selective Surface)," [online], 2021, [Retrieved January 16, 2024], Internet <URL: https: / / www.fujitsu.com / jp / solutions / business-technology / tc / fields / cae / poynting / fss.html> Summary of the Invention [Problem to be solved by the invention]

[0007] However, when used in a building under construction, for example, there is the issue that it is not possible to freely add communication equipment, making it difficult to use digital devices using, for example, wireless LAN in any location.

[0008] For example, Non-Patent Document 1 shows a repeater that does not require a power source, which is intended to reduce insertion loss due to the wall by embedding a waveguide within the wall and a circuit with antennas on both ends of the waveguide within the wall, and to suppress reflections by using an antenna and to extend the communication distance through antenna gain.

[0009] Furthermore, Non-Patent Document 2 discloses a method in which a metal mesh is attached to a plate material to match the impedance of a wall made of a high dielectric constant material with that of free space (air), and the impedance of the dielectric surface is determined according to the frequency band.

[0010] Furthermore, Non-Patent Document 3 discloses a method of periodically arranging metal patches or slots on a plane and using resonance to match impedance.

[0011] However, the repeater system shown in Non-Patent Document 1 requires the provision of a waveguide within the wall, which makes it difficult to put into practical use from the standpoint of ensuring flame retardancy.

[0012] Furthermore, even if the components shown in Non-Patent Documents 2 and 3 are attached to a wall and the impedance of the surface of the component is matched to the impedance of free space, insertion loss occurs due to the dielectric loss tangent of the wall.

[0013] The object of the present invention is to provide an electromagnetic wave matching device, an electromagnetic wave passing device, and a wall that can expand the communication range within a building and maintain wireless communication at any location without adding any additional communication equipment. [Means for solving the problem]

[0014] As an example of an electromagnetic wave matching device according to the present disclosure, a conductive plate facing at least the first surface of a dielectric member (such as a wall) having a first surface and a second surface facing each other, the conductive plate having a plurality of openings (non-conductive portions) through which a current of a predetermined frequency flows in a circumferential direction, and transmitting and receiving electromagnetic waves mainly composed of magnetic field energy in a direction perpendicular to the first surface; a facing distance between the dielectric member and the conductor plate is a distance at which a composite power of a wave reflected by the dielectric member and a wave reflected by the conductor plate at the predetermined frequency is reduced by a phase difference caused by the electromagnetic wave traveling back and forth between the dielectric member and the conductor plate, The present invention is characterized in that the electromagnetic wave transmission path between the dielectric member and the conductive plate, the dielectric member, and the free space outside the conductive plate is impedance matched.

[0015] As an example of an electromagnetic wave passing device according to the present disclosure, a first resonant circuit provided on a first surface of a dielectric member (such as a wall) having a first surface and a second surface facing each other, the first resonant circuit resonating at a predetermined frequency; a second resonant circuit provided on the second surface and resonating at the predetermined frequency; Equipped with The first resonant circuit and the second resonant circuit are electromagnetically coupled mainly via a magnetic field (mainly magnetic field coupling).

[0016] An example wall of the present disclosure may include: The device is characterized by comprising the dielectric member, the electromagnetic wave matching device and / or the electromagnetic wave passing device. [Effects of the Invention]

[0017] According to the present invention, an electromagnetic wave matching device, an electromagnetic wave passing device, and a wall are provided that can expand the communication range within a building and maintain wireless communication at any location without adding any additional communication equipment. [Brief explanation of the drawings]

[0018] [Figure 1] 1A and 1B are partial cross-sectional views of the electromagnetic wave matching device 101A according to the first embodiment and a wall 301A provided with the same, respectively. [Figure 2] 2 is a see-through perspective view of another electromagnetic wave matching device 101, 102 according to the first embodiment and a wall 301B equipped with the same, and the lower part of FIG. 2 is a cross-sectional view of the wall 301B. [Figure 3] FIG. 3 is a cross-sectional view of a wall 302A provided with an electromagnetic wave passing device according to the second embodiment. [Figure 4]FIG. 4 is a cross-sectional view of a wall 302B in which electromagnetic wave passing devices 201 and 202 are arranged in an array in the column direction or the plane direction of the wall main body 1. [Figure 5] FIG. 5 is a perspective view showing the configuration of the first resonant circuit RC1. [Figure 6] FIG. 6 is a diagram showing frequency characteristics of the S parameters of the first resonant circuit RC1 shown in FIG. [Figure 7] FIG. 7 is a perspective view of wall 302A. [Figure 8] FIG. 8 is a diagram showing the results of a simulation of the direction and strength of the current flowing through the inner split ring conductor SRI and the outer split ring conductor SRO of the first resonant circuit RC1 and the second resonant circuit RC2. [Figure 9] FIG. 9 is a diagram showing the results of a simulation of the direction and strength of the magnetic field generated near the first resonant circuit RC1 and the second resonant circuit RC2. [Figure 10] FIG. 10 is an equivalent circuit diagram of the wall 302A shown in FIG. [Figure 11] FIG. 11 is a diagram showing frequency characteristics of the insertion coefficient S21 and the reflection coefficient S11 of the wall main body 1 alone in a state in which the electromagnetic wave passing devices 201 and 202 shown in FIG. 7 are not present. [Figure 12] FIG. 12 shows the results of a simulation of the frequency characteristics of the wall insertion coefficient S21 in a state where an infinite number of electromagnetic wave transmission devices 201 and 202 shown in FIG. 7 are arranged in an array in the vertical and horizontal directions on the surface of the wall main body 1, and in a state where neither electromagnetic wave transmission device 201 nor electromagnetic wave transmission device 202 is present. [Figure 13] FIG. 13 is an exploded perspective view of the resonator device according to the third embodiment. [Figure 14] FIG. 14 is a diagram showing a single resonant circuit RC1 among the plurality of resonant circuits RC shown in FIG. 13, and a resonant circuit RC2 facing the resonant circuit RC1 across the wall main body. [Figure 15] FIG. 15 is a diagram showing the results of simulating the direction and intensity of currents flowing through the split ring resonators SRR1 and SRR2 and the probes PR1 and PR2 of the resonant circuits RC1 and RC2. [Figure 16] FIG. 16 is a diagram showing an example of a connection structure between the split ring resonator SRR1 and an antenna. [Figure 17] The upper part of Fig. 17 is a perspective view of a wall 304A including an electromagnetic wave passing device according to the fourth embodiment, and the lower part of Fig. 17 is a perspective view showing the resonance modes of the first dielectric resonator DR1 and the second dielectric resonator DR2, and the coupling mode between the first dielectric resonator DR1 and the second dielectric resonator DR2. [Figure 18] FIG. 18 is a diagram showing frequency characteristics of S parameters of the electromagnetic wave passing device shown in FIG. [Figure 19] The upper part of Fig. 19 is a perspective view of a wall 304B including another electromagnetic wave passing device according to the fourth embodiment, and the lower part of Fig. 19 is a perspective view showing the resonance modes of the first dielectric resonator DR1 and the second dielectric resonator DR2, and the coupling mode between the first dielectric resonator DR1 and the second dielectric resonator DR2. [Figure 20] FIG. 20 is a cross-sectional view of a wall 305 according to the fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0019] Hereinafter, several specific examples will be given with reference to the drawings to illustrate multiple embodiments for carrying out the present invention. The same reference numerals are used for the same parts in each drawing. To facilitate explanation and understanding of the main points, the embodiments for carrying out the present invention will be shown in multiple embodiments, but partial omission, substitution, or combination of the configurations shown in different embodiments is possible. From the second embodiment onwards, descriptions of matters common to the first embodiment will be omitted, and only the differences will be described. In particular, similar effects resulting from similar configurations will not be mentioned in each embodiment.

[0020] First Embodiment In the first embodiment, an electromagnetic wave matching device will be illustrated.

[0021] FIG. 1 is a partial cross-sectional view of an electromagnetic wave matching device 101 according to the first embodiment and a wall 301A provided with the same.

[0022] Wall 301A is composed of wall main body 1 and electromagnetic wave matching device 101. Wall 301A is, for example, a wall separating rooms in a building. Wall main body 1 is a wall material serving as a structural member of a building, such as concrete or lightweight aerated concrete (ALC), or a wall material serving as a non-structural member of a building, such as gypsum board (PB).

[0023] The wall main body 1 has a first surface S1 and a second surface S2 that face each other. The wall main body 1 is an example of the "dielectric member" according to the present invention.

[0024] As will be described later, the electromagnetic wave matching device 101 includes a conductive plate that reflects and transmits (transmits) electromagnetic waves at a predetermined ratio. The conductive plate is disposed parallel to the surface of the wall main body 1 at a predetermined interval.

[0025] In the wall 301A, the electromagnetic wave matching device 101 faces at least the first surface S1 of the wall main body 1, and passes electromagnetic waves mainly composed of magnetic field energy in a direction perpendicular to the first surface S1.

[0026] The conductive plate of the electromagnetic wave matching device 101 transmits a portion of the incident electromagnetic wave and reflects the remainder. In the example shown in the upper part of Figure 1, the electromagnetic wave that passes through the conductive plate is reflected by the first surface S1, and the remainder passes through the wall main body 1.

[0027] The opposing distance between the wall main body 1 and the conductive plates 21, 22 is 1 / 4 or approximately 1 / 4 of the wavelength λc of the electromagnetic wave at a predetermined frequency between the wall main body 1 and the conductive plates 21, 22. Here, the "predetermined frequency" refers to the frequency band that is intended to pass through the wall main body 1. Therefore, the reflected wave from the conductive plate and the reflected wave from the first surface S1 are in an antiphase relationship or a nearly antiphase relationship. The ratio of reflection to transmission from the conductive plate is determined so that the energy of the electromagnetic wave reflected from the conductive plate of the electromagnetic wave matching device 101 is approximately equal to the energy of the electromagnetic wave reflected from the first surface S1 of the wall main body 1. This causes the two reflected waves to cancel each other out. In other words, the electromagnetic wave incident on the first surface of the wall main body 1 from free space passes through the wall main body 1 with reduced reflection loss.

[0028] The opposing distance between the wall main body 1 (dielectric member) and the conductor plates 21, 22 may be any distance at which the combined power of the reflected waves from the wall main body 1 and the reflected waves from the conductor plates 21, 22 in the frequency band to be passed through the wall main body 1 is reduced by a phase difference caused by the electromagnetic waves traveling back and forth between the wall main body 1 and the conductor plates 21, 22. Therefore, the opposing distance between the wall main body 1 and the conductor plates 21, 22 is not limited to ¼ of the wavelength λc of the electromagnetic waves in a predetermined frequency band between the wall main body 1 and the conductor plates 21, 22.

[0029] In the example shown in the lower part of Fig. 1, electromagnetic waves incident from the second surface S2 side of the wall main body 1 are reflected by the first surface S1 of the wall main body 1 and are also reflected by the conductive plate, while the remainder passes through the conductive plate.

[0030] The energy of the electromagnetic wave reflected by the conductive plate of the electromagnetic wave matching device 101 is approximately equal to the energy of the electromagnetic wave reflected by the first surface S1 of the wall main body 1. As a result, the two reflected waves cancel each other out. That is, the electromagnetic wave that passes through the wall main body 1 and is emitted into free space is propagated into free space with reduced reflection loss.

[0031] 2 is a see-through perspective view of another electromagnetic wave matching device 101, 102 according to the first embodiment and a wall 301B equipped with the same, and the lower part of FIG. 2 is a cross-sectional view of the wall 301B.

[0032] The electromagnetic wave matching device 101 is provided on the first surface S1 side of the wall main body 1, and the electromagnetic wave matching device 102 is provided on the second surface S2 side of the wall main body 1.

[0033] The electromagnetic wave matching device 101 is composed of a conductor plate 21 and a dielectric layer 41. The conductor plate 21 is, for example, a copper plate or copper foil, and is attached to the first surface S1 of the wall main body 1 via the dielectric layer 41. The dielectric constant of the dielectric layer 41 is lower than the dielectric constant of the wall main body 1. In other words, the low-dielectric-constant dielectric layer 41 is interposed between the wall main body 1 and the conductor plate 21.

[0034] The opposing distance between the first surface S1 of the wall main body 1 and the conductor plate 21 is 1 / 4 or near 1 / 4 of the wavelength λc of the electromagnetic wave at a predetermined frequency between the wall main body 1 and the conductor plate 21. Similarly, the opposing distance between the second surface S2 of the wall main body 1 and the conductor plate 22 is 1 / 4 or near 1 / 4 of the wavelength λc of the electromagnetic wave at a predetermined frequency between the wall main body 1 and the conductor plate 22.

[0035] Therefore, the reflected wave from the conductor plate 21 and the reflected wave from the first surface S1 are in an antiphase relationship. The ratio of reflection to transmission from the conductor plate 21 is determined so that the energy of the electromagnetic wave reflected from the conductor plate 21 of the electromagnetic wave matching device 101 is approximately equal to the energy of the electromagnetic wave reflected from the first surface S1 of the wall main body 1. This causes the two reflected waves to cancel each other out.

[0036] Furthermore, the reflected wave from the conductive plate 22 and the reflected wave from the second surface S2 are in an antiphase relationship. The ratio of reflection to transmission from the conductive plate 22 is determined so that the energy of the electromagnetic wave reflected from the conductive plate 22 of the electromagnetic wave matching device 102 is approximately equal to the energy of the electromagnetic wave reflected from the second surface S2 of the wall main body 1. This causes the two reflected waves to cancel each other out.

[0037] 1, the opposing distance between the wall main body 1 and the conductor plates 21, 22 may be any distance at which the combined power of the waves reflected by the wall main body 1 and the waves reflected by the conductor plates 21, 22 in the frequency band to be passed through the wall main body 1 is reduced by the phase difference caused by the electromagnetic waves traveling back and forth between the wall main body 1 and the conductor plates 21, 22. Therefore, the opposing distance between the wall main body 1 and the conductor plates 21, 22 is not limited to ¼ of the wavelength λc of the electromagnetic waves in a predetermined frequency band between the wall main body 1 and the conductor plates 21, 22.

[0038] In this way, by providing the electromagnetic wave matching devices 101, 102 on both sides of the wall main body 1, impedance matching is achieved for the electromagnetic wave transmission paths between the wall main body 1 and the conductor plates 21, 22, the dielectric layers 41, 42, and the free space outside the conductor plates 21, 22. Therefore, reflection loss at the first surface S1 and the second surface S2 of the wall main body 1 for the electromagnetic waves propagating from one free space to another through the wall main body 1 is effectively suppressed.

[0039] The conductive plate 21 has a plurality of arranged openings (non-conductive portions) 31. Seven circular openings 31 are shown in FIG. 2. That is, the plurality of openings 31 are air (non-conductive portions). The openings 31 are, for example, punched holes arranged periodically in a metal plate such as a copper plate. The radius of the openings 31 is, for example, 40 mm, and the spacing between adjacent openings 31 is 4 mm. This radius of 40 mm is one example. The spacing of 4 mm between adjacent openings 31 is determined so that the reflectance of the conductive plate 21 having these openings 31 becomes a predetermined value (reflection coefficient on the first surface S1 of the wall main body portion 1). This spacing of 4 mm between openings 31 is also one example.

[0040] The thickness of the conductor plates 21 and 22 is, for example, 3 mm, and the distance between the conductor plate 21 and the first surface S1 of the wall main body 1 and the distance between the conductor plate 22 and the second surface S2 of the wall main body 1 are, for example, 50 mm, respectively.

[0041] Around each of the openings 31, a current of a predetermined frequency to be passed through the wall main body 1 flows in the circumferential direction of each of the openings 31. In other words, these openings 31 have a gain at a specific frequency as an antenna. This makes it easier for magnetic field energy to be transmitted in a direction perpendicular to the first surface S1 of the wall main body 1. In other words, the conductor plate 21 transmits and receives electromagnetic waves that are mainly composed of magnetic field energy in a direction perpendicular to the first surface S1 of the wall main body 1.

[0042] The above description concerns the conductor plate 21, but the same applies to the conductor plate 22. In other words, the electromagnetic wave matching device 102 is composed of the conductor plate 22 and the dielectric layer 42. The conductor plate 22 is, for example, a copper plate or copper foil, and this conductor plate 22 is attached to the second surface S2 of the wall main body 1 via the dielectric layer 42. The dielectric constant of the dielectric layer 42 is lower than the dielectric constant of the wall main body 1. In other words, the low-dielectric-constant dielectric layer 42 is interposed between the wall main body 1 and the conductor plate 22.

[0043] The conductor plate 22 also has seven circular openings 32. A current of a predetermined frequency that is to be passed through the wall main body 1 flows in a circumferential direction around each of the openings 32. This facilitates transmission of magnetic field energy in a direction perpendicular to the second surface S2 of the wall main body 1. That is, the conductor plate 22 transmits or receives electromagnetic waves that are mainly composed of magnetic field energy in a direction perpendicular to the second surface S2 of the wall main body 1.

[0044] The upper and lower diagrams in FIG. 2 show input / output ports P1 and P2 for measuring the transmission characteristics of the wall 301B.

[0045] The openings 31 and 32 reduce the reflectance of the conductive plates 21 and 22 to a predetermined amount. That is, the reflectance is set to be approximately equal to the reflectance of the first surface S1 and the second surface S2 of the wall main body 1. The reflectance of the conductive plates 21 and 22 can be determined by the size of the openings 31 and 32, the opening area ratio, etc.

[0046] In this example, the current flowing in the circumferential direction of each of the openings 31 and 32 increases the magnetic field energy in the Z direction, which is the direction perpendicular to the current loop plane.

[0047] In Figure 2, the arrow of the magnetic field H indicates the magnetic field direction, and the arrow of the electric field E indicates the electric field direction. In this way, a plane wave (electromagnetic field is only X and Y vectors) is incident on each opening 31 and passes through as is. This reduces loss due to the dielectric loss tangent of the wall main body 1, which is a dielectric. In particular, it is preferable that the center of each opening 31 and the center of the opposing opening 32 coincide in the Z direction. This improves the coupling between the opening 31 acting as an antenna and the opening 32 acting as an antenna, and increases the magnetic field energy passing through the wall main body 1.

[0048] In the example shown in FIG. 2, the openings 31 and 32 are arranged in an array in the planar direction of the conductive plates 21 and 22, but the openings 31 and 32 may also be arranged in a column direction.

[0049] 2, the distance between the conductive plate 21 and the first surface S1 of the wall main body 1 and the distance between the conductive plate 22 and the second surface S2 of the wall main body 1 may be set to a plurality of different distances depending on the frequency bands of the communication signals, or the distance to the second surface S2 of the wall main body 1 may be set to a plurality of different distances depending on the width of the frequency band of the communication signals. This makes it possible to obtain low return loss characteristics over a plurality of frequency bands or a wide frequency band.

[0050] Furthermore, the size of the openings 31 and 32 may be uniform, but when there are multiple frequency bands for communication signals, multiple sizes of the openings 31 and 32 having antenna gain may be provided according to the frequency bands. This makes it possible to set multiple types of antenna gain according to the frequency band, or to set the antenna gain to a predetermined value over a wide band. This also makes it possible to pass multiple types of communication signals in different frequency bands with low return loss.

[0051] 2, the openings 31 and 32 are circular, but they may be slit-shaped. The direction of the slit may be determined according to the polarization of the electromagnetic wave to be passed through the wall main body (the direction of the polarization axis for linear polarization, or the direction of rotation for circular polarization). The openings may also be n-sided, such as a square.

[0052] Second Embodiment In the second embodiment, an electromagnetic wave passing device will be illustrated.

[0053] 3 is a cross-sectional view of a wall 302A equipped with an electromagnetic wave passing device according to the second preferred embodiment. Wall 302A includes a wall main body 1 and electromagnetic wave passing devices 201 and 202. Wall main body 1 corresponds to the "dielectric member" according to the present invention. The detailed configurations of electromagnetic wave passing devices 201 and 202 will be described later.

[0054] The electromagnetic wave passing device 201 is provided on the first surface S1 of the wall main body 1 and includes a first resonant circuit that resonates at a predetermined frequency. The electromagnetic wave passing device 202 is provided on the second surface S2 of the wall main body 1 and includes a second resonant circuit that resonates at a predetermined frequency. The predetermined frequency is the frequency of the electromagnetic wave that is to pass through the wall main body 1 with low loss.

[0055] The first resonant circuit of electromagnetic wave passing device 201 and the second resonant circuit of electromagnetic wave passing device 202 are electromagnetically coupled mainly via a magnetic field (mainly magnetic field coupling).

[0056] 4 is a cross-sectional view of a wall 302B in which electromagnetic wave passing devices 201, 202 are arranged in an array in the column direction or plane direction relative to the wall main body 1. The electromagnetic wave passing devices 201 and 202 are paired and arranged on the first surface S1 and second surface S2 of the wall main body 1 so as to sandwich the wall main body 1 therebetween.

[0057] In this way, the electromagnetic wave passing devices 201 and 202 may be arranged in an array, thereby making it possible to further reduce the electromagnetic wave excess loss in the wall main body 1.

[0058] The first resonant circuit of electromagnetic wave passing device 201 and the second resonant circuit of electromagnetic wave passing device 202 have the same configuration. Both are formed in a sheet shape and are made up of a plurality of conductor patterns having inductance components and capacitance components.

[0059] The electromagnetic wave passing devices 201 and 202 shown in FIG. 4 may all resonate at the same frequency, but the plurality of resonant circuits arranged in an array along the wall main body 1 may be configured with a plurality of types of resonant circuits with different resonant frequencies. This makes it possible to widen the frequency band with low insertion loss. Also, the electromagnetic wave passing devices 201 and 202 may be configured with a plurality of types of resonant circuits with different resonant frequencies according to the different frequency bands of communication signals. This makes it possible to pass a plurality of types of communication signals with different frequency bands with low insertion loss.

[0060] Fig. 5 is a perspective view showing the configuration of the first resonant circuit RC1. In the example shown in Fig. 5, an outer split ring conductor SRO and an inner split ring conductor SRI are formed on a dielectric sheet 5. The outer split ring conductor SRO and the inner split ring conductor SRI are both ring-shaped conductors opened at splits SP. The outer split ring conductor SRO and the inner split ring conductor SRI have an inductance component of the conductor pattern and a capacitance component formed at the splits SP, forming an LC resonant circuit.

[0061] The resonant circuit formed by the outer split ring conductor SRO and the resonant circuit formed by the inner split ring conductor SRI are electromagnetically coupled (capacitively and inductively).The resonant circuit formed by the outer split ring conductor SRO and the resonant circuit formed by the inner split ring conductor SRI form one resonant circuit.

[0062] Since an alternating current flows through the outer split ring conductor SRO and the inner split ring conductor SRI of the first resonant circuit RC1 in the direction circulating the ring at the resonant frequency, an electromagnetic field is generated in which the magnetic field passes through the opening of the inner split ring conductor SRI during transmission. That is, the first resonant circuit RC1 resonates in a mode in which a magnetic field is generated in the direction of propagation of the electromagnetic wave (perpendicular to the surface of the wall main body 1).

[0063] In this way, the first resonant circuit RC1 and the second resonant circuit RC2 are coupled mainly via a magnetic field, so that almost no dielectric loss occurs due to the dielectric loss tangent of the dielectric of the wall main body, and therefore the insertion loss of the wall main body is low.

[0064] Fig. 6 is a diagram showing the frequency characteristics of the S parameters of the first resonant circuit RC1 shown in Fig. 5. In the example shown in Fig. 6, the reflection coefficient S11 is minimum and the insertion coefficient S21 is maximum at the low channel frequency of the 2.4 GHz band used in wireless LAN.

[0065] Fig. 7 is a perspective view of wall 302A. The upper part of Fig. 7 shows the positional relationship between electromagnetic wave passing device 201 formed by a first resonant circuit RC1 provided on a first surface of wall main body 1, and electromagnetic wave passing device 202 formed by a second resonant circuit RC2 provided on a second surface of wall main body 1. The lower part of Fig. 7 also shows input / output ports P1 and P2 for obtaining the characteristics of wall 302A. In Fig. 7, the two-dot chain line indicates that electromagnetic wave passing device 201 and electromagnetic wave passing device 202 are parallel to each other, sandwiching wall main body 1 therebetween. With regard to wall main body 1, only the area surrounded by the two-dot chain line is shown.

[0066] In Figure 7, the direction of current flow in the resonator formed by the inner split-ring conductor SRI and the outer split-ring conductor SRO is indicated by current i. In other words, current i flows in a plane parallel to the XY plane. As a result, the main component of the magnetic field H is oriented parallel to the Z axis, as indicated by the dashed arrow in Figure 7.

[0067] FIG. 8 shows the results of a simulation of the direction and intensity of the current flowing through the inner split ring conductor SRI and the outer split ring conductor SRO of the first resonant circuit RC1 and the second resonant circuit RC2.

[0068] FIG. 9 shows the results of a simulation of the direction and strength of the magnetic field generated near the first resonant circuit RC1 and the second resonant circuit RC2.

[0069] In this way, an alternating current flows through the outer split ring conductor SRO and the inner split ring conductor SRI of the first resonant circuit RC1 in a direction circulating around the ring at the resonant frequency. During transmission, an electromagnetic field is generated in which the magnetic field passes through the opening of the inner split ring conductor SRI. This electromagnetic field passes through the opening of the inner split ring conductor SRI of the second resonant circuit RC2, and an alternating current flows through the outer split ring conductor SRO and the inner split ring conductor SRI of the second resonant circuit RC2 in a direction circulating around the ring at the resonant frequency. In other words, the first resonant circuit RC1 and the second resonant circuit RC2 are primarily magnetically coupled, causing the second resonant circuit RC2 to resonate. This resonance of the second resonant circuit RC2 allows electromagnetic waves to pass through the opening of the inner split ring conductor SRI of the second resonant circuit RC2, with the magnetic field passing through the opening.

[0070] 5, 7, 8, and 9, the split ring conductors are circular, but they may be square or rectangular. The orientation of the split ring conductors may be determined according to the polarization of the electromagnetic waves to be passed through the wall main body (the polarization axis direction for linear polarization, or the rotation direction for circular polarization).

[0071] Fig. 10 is an equivalent circuit diagram of the first resonant circuit RC1 and the second resonant circuit RC2 shown in Fig. 7. In Fig. 10, inductor L1 is the inductance component of the outer split ring conductor SRO and the inner split ring conductor SRI of the first resonant circuit RC1, capacitor C1 is the capacitance component that mainly occurs at the split SP of the outer split ring conductor SRO and the split SP part of the inner split ring conductor SRI of the first resonant circuit RC1, and resistor R1 is the resistance component of the outer split ring conductor SRO and the inner split ring conductor SRI of the first resonant circuit RC1.

[0072] Inductor L2 is the inductance component of the outer split ring conductor SRO and the inner split ring conductor SRI of the second resonant circuit RC2, capacitor C2 is the capacitance component that mainly occurs at the split SP of the outer split ring conductor SRO and the split SP part of the inner split ring conductor SRI of the second resonant circuit RC2, and resistor R2 is the resistance component of the outer split ring conductor SRO and the inner split ring conductor SRI of the second resonant circuit RC2.

[0073] Inductor L1 and inductor L2 are magnetically coupled. A power source Ps is connected to the first resonant circuit RC1. This power source Ps is an input section for electromagnetic waves that are connected from free space to the first resonant circuit RC1. The first resonant circuit RC1 resonates including the power source Ps.

[0074] 10, a load Ro is connected to the second resonant circuit RC2. This load Ro is a resistance component related to the radiation of electromagnetic waves into free space. The second resonant circuit RC2 resonates including the load Ro.

[0075] Fig. 11 is a diagram showing frequency characteristics of the insertion coefficient S21 and the reflection coefficient S11 in a state where the electromagnetic wave passing devices 201, 202 of the wall 302A shown in Fig. 7 are not present, that is, in the case of the wall main body 1 alone. The upper part of Fig. 11 is a diagram showing the coefficients in the range of 0 dB to -40 dB, and the lower part of Fig. 11 is a diagram showing the coefficients in the range of 0 dB to -10 dB.

[0076] Here, the relative dielectric constant of the wall main body 1 is 5.3, tan δ is 0.1, and the thickness is 15 mm. There is air between the ports P1, P2 and the wall main body 1, and the relative dielectric constant of the air is 1.0. The wall main body 1 is, for example, a gypsum board.

[0077] In this example, at 2.45 GHz the insertion factor S21 is -3 dB, i.e. only half the power is passed through.

[0078] Fig. 12 shows the results of simulating the frequency characteristics of the wall insertion coefficient S21 in a state where an infinite number of electromagnetic wave passage devices 201 and electromagnetic wave passage devices 202 shown in Fig. 7 are arranged in an array in the vertical and horizontal directions on the surface of wall main body 1, and in a state where electromagnetic wave passage devices 201 and electromagnetic wave passage devices 202 are not present. The upper part of Fig. 12 is a graph showing the insertion coefficient S21 in the range of 0 dB to -30 dB, and the lower part of Fig. 12 is a graph showing the insertion coefficient S21 in the range of 0 dB to -10 dB.

[0079] 7 does not exist, S21 is approximately -3 dB in the 2.45 GHz band used in wireless LAN. On the other hand, when the electromagnetic wave passing device 201 and electromagnetic wave passing device 202 of the wall 302A are present, S21 is approximately -2 dB in the 2.45 GHz band (the resonant frequency band of the first resonant circuit RC1 and the second resonant circuit RC2).

[0080] Thus, according to this embodiment, the presence of electromagnetic wave passing device 201 and electromagnetic wave passing device 202 improves insertion coefficient S21 by approximately 1 dB.

[0081] As described above, according to this embodiment, an electromagnetic wave passing device that passes communication signals in a predetermined frequency band with low loss can be obtained.

[0082] Third Embodiment In the third embodiment, a resonant device including a coupler element and a resonant circuit will be exemplified.

[0083] 13 is an exploded perspective view of a resonance device according to a third embodiment, which includes a resonance circuit RC and a coupler element CE.

[0084] The resonant circuit RC is composed of a dielectric sheet 5 and split ring resonators SRR arranged in an array on this dielectric sheet 5. The split ring resonators SRR are composed of an outer split ring conductor SRO and an inner split ring conductor SRI. This basic configuration is the same as the resonant circuit shown in Figure 5 etc. in the second embodiment.

[0085] The coupler element CE is composed of a dielectric sheet 6 and an antenna ANT made of a circular conductor pattern arranged in an array on this dielectric sheet.

[0086] Each antenna ANT of the coupler element CE faces each split ring resonator SRR of the resonant circuit RC. Among the antennas ANT arranged in an array and the split ring resonators SRR arranged in an array, the adjacent antennas ANT and split ring resonators SRR are connected to each other.

[0087] FIG. 14 shows a single resonant circuit RC1 among the plurality of resonant circuits RC shown in FIG. 13, and a resonant circuit RC2 facing the resonant circuit RC1 across the wall main body.

[0088] The conductor pattern of the probe PR1 is formed on the same surface as the split ring resonator SRR1 and is adjacent to it. This probe PR1 is electromagnetically coupled to the split ring resonator SRR1. The base AB1 of the probe PR1 is connected to the radiation electrode of the patch antenna (the antenna ANT shown in Figure 13). The antenna is not shown in Figure 14.

[0089] The configuration of the resonant circuit RC2 is the same as that of the resonant circuit RC1. The conductor pattern of the probe PR2 is formed on the same surface as the split ring resonator SRR2, adjacent to it. This probe PR2 is electromagnetically coupled to the split ring resonator SRR2. The base AB2 of the probe PR2 is connected to the radiating electrode of the patch antenna.

[0090] 15 shows the results of simulating the direction and strength of the current flowing through the split ring resonators SRR1 and SRR2 and the probes PR1 and PR2 of the resonant circuits RC1 and RC2. As such, due to the current flowing through the split ring resonators SRR1 and SRR2 and the probes PR1 and PR2 of the resonant circuits RC1 and RC2, the probe PR1 is electromagnetically coupled to the split ring resonator SRR1, and the probe PR2 is electromagnetically coupled to the split ring resonator SRR2.

[0091] Fig. 16 is a diagram showing an example of a connection structure between a split ring resonator SRR and an antenna. The upper part of Fig. 16 is a perspective view of one unit of a device composed of a split ring resonator SRR and an antenna. The lower part of Fig. 16 is a cross-sectional view of the dashed line portion in the upper part of Fig. 16.

[0092] This device is a laminated substrate having three resin layers, each with a conductor pattern made of Cu foil formed on one side. A split ring resonator SRR is formed on the top surface of the upper resin layer. A conductor pattern for the probe PR and a ground conductor layer GND are formed on the middle resin layer. The pattern of this ground conductor layer GND is a pattern with an opening positioned along the opening of the split ring resonator SRR. A radiating electrode RE is formed on the lower resin layer. This radiating electrode RE, the ground conductor layer GND, and the resin layer between the radiating electrode RE and the ground conductor layer GND form a patch antenna. The pattern of the radiating electrode RE is a pattern with an opening positioned along the opening of the split ring resonator SRR.

[0093] As shown in the upper part of Fig. 16, the conductor pattern of the probe PR is electromagnetically coupled to the split ring resonator SRR. One end of the conductor pattern of the probe PR is connected to the radiation electrode RE through a via hole V. The other end is connected to the ground conductor layer GND.

[0094] With the structure described above, the antenna ANT shown in FIG. 13 receives electromagnetic waves in the frequency band that is intended to pass through the wall main body, and resonates with those electromagnetic waves, causing the antenna ANT to resonate the split ring resonator SRR.

[0095] As shown in the second embodiment, the resonant mode of the split ring resonator SRR is a mode in which an electromagnetic field is generated in which the magnetic field passes through the opening of the inner split ring conductor SRI, and therefore the split ring resonators of the resonant circuit RC that face each other across the wall main body are magnetically coupled to each other.

[0096] According to this embodiment, the gain of the antenna ANT for electromagnetic waves propagating through free space can be increased and the insertion loss of the wall main body can be reduced, so that the insertion loss of the electromagnetic wave passing device can be effectively reduced.

[0097] Fourth Embodiment In the fourth embodiment, an electromagnetic wave passing device using a dielectric resonator will be illustrated.

[0098] The upper part of Fig. 17 is a perspective view of a wall 304A equipped with an electromagnetic wave passing device according to the fourth embodiment. In this example, a first dielectric resonator DR1 is arranged on a first surface S1 of the wall main body 1, and a second dielectric resonator DR2 is arranged on a second surface S2 of the wall main body 1. The first dielectric resonator DR1 and the second dielectric resonator DR2 face each other via the wall main body 1. The surface enclosed by the dashed line near the first dielectric resonator DR1 is indicated as an input port, and the surface enclosed by the dashed line near the second dielectric resonator DR2 is indicated as an output port.

[0099] The lower part of Fig. 17 is a perspective view showing the resonance modes of the first dielectric resonator DR1 and the second dielectric resonator DR2, and the coupling mode between the first dielectric resonator DR1 and the second dielectric resonator DR2. When the first dielectric resonator DR1 and the second dielectric resonator DR2 resonate, an electric field loop parallel to the XY plane is generated, and a magnetic field is generated in the thickness direction of the wall main body 1 (a direction parallel to the Z axis). The first dielectric resonator DR1 and the second dielectric resonator DR2 are magnetically coupled.

[0100] In the example shown in Figure 17, only a pair of dielectric resonators is shown, but the first dielectric resonator DR1 and the second dielectric resonator DR2 may be arranged in an array in the vertical and horizontal directions along the first surface S1 and the second surface S2 of the wall main body portion 1.

[0101] The dielectric resonators DR1 and DR2 also function as antennas. For example, the first dielectric resonator DR1 resonates with electromagnetic waves propagating from free space on the first surface S1 side of the wall main body, and orients the magnetic field in the thickness direction of the wall main body 1. The second dielectric resonator DR2 is magnetically coupled with the first dielectric resonator DR1 and emits electromagnetic waves into free space on the second surface S2 side of the wall main body. This makes it easier for magnetic field energy to be transmitted in a direction perpendicular to the first surface S1 of the wall main body 1.

[0102] Fig. 18 is a diagram showing the frequency characteristics of the S parameters of the electromagnetic wave passing device shown in Fig. 17. In the example shown in Fig. 18, the reflection coefficient S11 is minimum and the insertion coefficient S21 is maximum at the low channel frequency of the 2.4 GHz band used in wireless LAN. Note that the reflection coefficient S11 and the insertion coefficient S21 are determined by the resonance frequency due to the coupling of the dielectric resonators DR1 and DR2. However, since odd-mode resonance and even-mode resonance occur between the two resonators, as shown by the reflection coefficient S11 in Fig. 18, the overall resonance frequency is separated above and below by a predetermined frequency from the resonance frequency of each of the dielectric resonators DR1 and DR2 alone. This results in low insertion loss over a relatively wide band.

[0103] Fig. 19 is a perspective view of a wall 304B provided with another electromagnetic wave passing device according to the fourth embodiment. The upper part of Fig. 19 is a perspective view of the wall 304B provided with the electromagnetic wave passing device. The lower part of Fig. 19 is a perspective view showing the resonance modes of the first dielectric resonator DR1 and the second dielectric resonator DR2, and the coupling mode between the first dielectric resonator DR1 and the second dielectric resonator DR2. In the example shown in Fig. 17, the first dielectric resonator DR1 and the second dielectric resonator DR2 were both rectangular parallelepiped shaped, but the first dielectric resonator DR1 and the second dielectric resonator DR2 shown in Fig. 19 are both cylindrical dielectric resonators.

[0104] 19, the first dielectric resonator DR1 and the second dielectric resonator DR2 resonate in the TE011 mode, and this resonance generates an electric field loop parallel to the XY plane and generates a magnetic field in the thickness direction (parallel to the Z axis) of the wall main body 1. The first dielectric resonator DR1 and the second dielectric resonator DR2 are magnetically coupled.

[0105] In the example shown in Figure 19, only a pair of dielectric resonators is shown, but the first dielectric resonator DR1 and the second dielectric resonator DR2 may be arranged in an array in the vertical and horizontal directions along the first surface S1 and the second surface S2 of the wall main body portion 1.

[0106] Thus, the dielectric resonator may be cylindrical or may be circular ring-shaped.

[0107] Fifth Embodiment In the fifth embodiment, a wall including an electromagnetic wave passing device and an electromagnetic wave matching device will be exemplified.

[0108] 20 is a cross-sectional view of a wall 305 according to the fifth embodiment. The wall 305 includes a wall main body 1, electromagnetic wave passing devices 201 and 202, and electromagnetic wave matching devices 101 and 102.

[0109] An electromagnetic wave passing device 201 is arranged on the first surface S1 of the wall main body 1, and an electromagnetic wave matching device 101 is provided on the surface of this electromagnetic wave passing device 201. A combination of this electromagnetic wave passing device 201 and electromagnetic wave matching device 101 is arranged in an array in the column direction or the plane direction on the first surface S1 of the wall main body 1.

[0110] An electromagnetic wave passing device 202 is arranged on the second surface S2 of the wall main body 1, and an electromagnetic wave matching device 102 is provided on the surface of this electromagnetic wave passing device 202. A combination of this electromagnetic wave passing device 202 and electromagnetic wave matching device 102 is arranged in an array in the column direction or the plane direction on the second surface S2 of the wall main body 1.

[0111] Electromagnetic wave passing devices 201 and 202 facing each other so as to sandwich wall main body 1 act in the same manner as electromagnetic wave passing devices 201 and 202 shown in the second embodiment, allowing electromagnetic waves to pass through wall main body 1 with low insertion loss.

[0112] Furthermore, by providing the electromagnetic wave matching device 101 on the surface of the electromagnetic wave passing device 201, similar to the electromagnetic wave matching device 101 shown in the first embodiment, the electromagnetic wave matching device 101 reduces the reflection loss between free space and the electromagnetic wave passing device 201, i.e., at the surface of the electromagnetic wave passing device 201.

[0113] In FIG. 20, electromagnetic waves propagating in the Z direction are conceptually indicated by thick arrows, but the same applies to electromagnetic waves propagating in the −Z direction.

[0114] According to the present embodiment, the magnetic field coupling between the resonators of the electromagnetic wave passing devices 201 and 202 reduces the insertion loss of the wall main body 1 and also reduces the reflection loss on the surfaces of the electromagnetic wave passing devices 201 and 202. This results in a wall 305 with a smaller insertion loss.

[0115] 20 may all resonate at the same frequency, but the plurality of resonant circuits arranged in an array along the wall main body 1 may be configured with a plurality of types of resonant circuits with different resonant frequencies. This makes it possible to widen the frequency band with low insertion loss. Also, the electromagnetic wave passing devices 201 and 202 may be configured with a plurality of types of resonant circuits with different resonant frequencies according to the different frequency bands of communication signals. This makes it possible to pass a plurality of types of communication signals with different frequency bands with low insertion loss.

[0116] Furthermore, the size of the apertures provided in the electromagnetic wave matching devices 101 and 102 shown in Fig. 20 may be the same, or the apertures may be configured with apertures of different sizes corresponding to frequency bands having antenna gain. This allows the frequency band with low return loss to be broadened. Also, multiple apertures of different sizes may be arranged according to the different frequency bands of communication signals. This allows multiple communication signals of different frequency bands to pass with low return loss.

[0117] Various embodiments of the present invention have been presented so far, but these are all examples and are not intended to limit the scope of the present invention. Various omissions, substitutions, and modifications can be made to the embodiments of the present invention without departing from the spirit of the invention. Embodiments with such omissions, substitutions, and modifications are included within the scope and spirit of the present invention, and are also included in the scope of the invention and its equivalents as set forth in the claims of this application.

[0118] For example, the above description has been made with reference to the propagation of communication signals in the 2.4 GHz band, but the same can be applied to the propagation of communication signals in other frequency bands.

[0119] Furthermore, although the above explanation has mainly focused on the propagation of communication signals, it can also be applied to wireless power transmission.

[0120] Furthermore, in the above explanation, the wall main body 1 has been given as an example of the "dielectric member" according to the present invention, but the present invention can also be applied to ceilings, floors, and the like in the same way as well as walls. [Explanation of symbols]

[0121] ANT…antenna AB1: base of probe PR1 AB2: base of probe PR2 C1, C2...capacitors CE: Coupler element DR1: First dielectric resonator DR2: Second dielectric resonator E...electric field GND: Ground conductor layer H...magnetic field L1, L2...inductors P1, P2...input / output ports PR, PR1, PR2... probes Ps…Power source R1,R2…Resistance RC…Resonant circuit RC1...1st resonant circuit RC2…Second resonant circuit RE…Radiation electrode Ro...load S1...Side 1 S2...Side 2 SP...Split SRI...Inner Split Ring Conductor SRO...Outer split ring conductor SRR, SRR1, SRR2...Split ring resonator V...Beer hall 1...Wall body 5...Dielectric sheet 6...Dielectric sheet 21, 22...Conductor plates 31,32…Aperture 41, 42...Dielectric layers 101,101A,102...Electromagnetic wave matching device 201,202...Electromagnetic wave passing device 301A, 301B, 302A, 302B, 304A, 304B, 305...wall

Claims

1. a conductive plate facing at least the first surface of a dielectric member having a first surface and a second surface facing each other, the conductive plate having a plurality of non-conductive portions through which a current of a predetermined frequency flows in a circumferential direction, and allowing an electromagnetic wave, mainly consisting of magnetic field energy in a direction perpendicular to the first surface, to pass therethrough; a facing distance between the dielectric member and the conductor plate is a distance at which a composite power of a wave reflected by the dielectric member and a wave reflected by the conductor plate at the predetermined frequency is reduced by a phase difference caused by the electromagnetic wave traveling back and forth between the dielectric member and the conductor plate, impedance matching of an electromagnetic wave transmission path between the dielectric member and the conductor plate, the dielectric member, and a free space outside the conductor plate; Electromagnetic wave matching device.

2. a dielectric layer having a lower dielectric constant than the dielectric member is interposed between the conductive plate and the dielectric member; 2. The electromagnetic wave matching device according to claim 1.

3. a first resonant circuit provided on the first surface of a dielectric member having a first surface and a second surface facing each other, the first resonant circuit resonating at a predetermined frequency; a second resonant circuit provided on the second surface and resonating at the predetermined frequency; Equipped with the first resonant circuit and the second resonant circuit are electromagnetically coupled mainly via a magnetic field; Electromagnetic wave passing device.

4. The first resonant circuit and the second resonant circuit are formed in a sheet shape and are composed of a plurality of conductor patterns having inductance components and capacitance components.

4. The electromagnetic wave passing device according to claim 3.

5. one or both of the first resonant circuit and the second resonant circuit is a split ring resonator; 5. The electromagnetic wave passing device according to claim 4.

6. a plurality of antennas disposed adjacent to the plurality of resonant circuits and electromagnetically coupled to the plurality of resonant circuits, respectively; 6. The electromagnetic wave passing device according to claim 4 or 5.

7. one or both of the first resonant circuit and the second resonant circuit is a dielectric resonator; 4. The electromagnetic wave passing device according to claim 3.

8. the plurality of resonant circuits are arranged in an array along the dielectric member; 6. The electromagnetic wave passing device according to claim 3.

9. the plurality of resonant circuits arranged in an array along the dielectric member are composed of a plurality of types of resonant circuits having different resonant frequencies; 9. The electromagnetic wave passing device according to claim 8.

10. a conductive plate facing the first resonant circuit and having a plurality of non-conductive portions through which a current at the predetermined frequency flows in a circular direction; a facing distance between the dielectric member and the first resonant circuit is a distance at which a composite power of a wave reflected by the dielectric member and a wave reflected by the first resonant circuit at the predetermined frequency is reduced by a phase difference caused by the electromagnetic wave traveling back and forth between the dielectric member and the first resonant circuit, an impedance matching is performed between an electromagnetic wave transmission path between the first resonant circuit and the conductive plate and an electromagnetic wave transmission path through free space outside the conductive plate; 6. The electromagnetic wave passing device according to claim 3.

11. The dielectric member is a main body of a wall that separates the interior and exterior of a room, A wall comprising the electromagnetic wave matching device according to claim 1 or 2 and the main body.

12. The dielectric member is a main body of a wall that separates the interior and exterior of a room, A wall comprising the electromagnetic wave passing device according to claim 3 and the main body.

13. The dielectric member is a main body of a wall that separates the interior and exterior of a room, A wall comprising the electromagnetic wave passing device according to claim 10 and the main body.

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