Antenna device

Abstract

The antenna device is a device of a zero resonance antenna, which includes: a ground plate (40) providing a ground potential; a relative conductor (50) which is arranged to have a predetermined distance from the ground plate in the plate thickness direction of the ground plate and is configured to be connected to a feeder (60); and a short-circuit portion (70) electrically connecting the relative conductor and the ground plate. The antenna device also includes an intermediate conductor (80) which has the same potential as the ground plate and is arranged between the ground plate and the relative conductor in the plate thickness direction. The intermediate conductor includes a penetration portion (81) which includes the relative conductor in a plan view in the plate thickness direction.

Description

Technical Field

[0001] The present disclosure generally relates to an antenna device. Background Art

[0002] Patent Document 1 discloses an antenna device. The disclosure of this prior art document is incorporated herein by reference as an explanation of technical elements in the present disclosure.

[0003] (Patent Document 1) Japanese Patent Application Publication No. 2020-10135.

[0004] The antenna device of Patent Document 1 includes a 0th order resonant antenna using metamaterial technology. The 0th order resonant antenna has a narrow band (ie, a narrow frequency bandwidth). From the above viewpoints or other viewpoints not mentioned, the antenna device requires further improvement. Summary of the invention

[0005] An object of the present disclosure is to provide a broadband antenna device.

[0006] The antenna device disclosed here includes: a ground plate providing a ground potential; a relative conductor, which is arranged to be a predetermined distance away from the ground plate in the plate thickness direction of the ground plate and has a feeding point; a short-circuit portion, which electrically connects the relative conductor and the ground plate; and an intermediate conductor, which has the same potential as the ground plate and is arranged between the ground plate and the relative conductor in the plate thickness direction.

[0007] The intermediate conductor has a penetration portion penetrating the intermediate conductor in a plate thickness direction, and includes the opposing conductor in a plan view along the plate thickness direction.

[0008] In the disclosed antenna device, by providing the intermediate conductor having the penetration portion, a capacitor is also formed between the intermediate conductor and the opposite conductor. As a result, a resonance point is additionally formed. Therefore, an antenna device having a wide bandwidth can be provided.

[0009] The various aspects disclosed in this specification adopt different technical solutions from each other to achieve their respective purposes. The claims described in this section and the figure marks in brackets illustrate the corresponding relationship with the parts of the embodiments described later and are not used to limit the technical scope. The purposes, features and effects disclosed herein will be made clearer by referring to the subsequent detailed description and drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The objects, features and advantages of the present invention will become more apparent from the following detailed description with reference to the accompanying drawings, in which:

[0011] Figure 1 is a perspective view showing an electronic device to which the antenna device is applied.

[0012] Figure 2is an exploded perspective view showing the antenna device according to the first embodiment.

[0013] Figure 3 It is an enlarged plan view near the relative conductor.

[0014] Figure 4 is along Figure 3 A cross-sectional view taken along line IV-IV.

[0015] Figure 5 is a graph showing reflection characteristics.

[0016] Figure 6 is a diagram showing an inductor and a capacitor of an antenna device.

[0017] Figure 7 It is a plan view showing a modified example.

[0018] Figure 8 is a diagram showing electric field distribution.

[0019] Fig. 9 is a plan view showing an antenna device according to a second embodiment.

[0020] Fig.10 is a plan view showing an antenna device according to a third embodiment.

[0021] Fig.11 is the equivalent circuit diagram of the antenna device.

[0022] Fig.12 is a graph showing reflection characteristics.

[0023] Fig.13 is a plan view showing an antenna device according to a fourth embodiment.

[0024] Fig.14 is along Fig.13 A cross-sectional view taken along line XIV-XIV.

[0025] Fig.15 It is a plan view showing a modified example.

[0026] Fig.16 is along Fig.15 A cross-sectional view taken along line XVI-XVI.

[0027] Fig.17 is a plan view showing a modified example. and

[0028] Fig.18 is along Fig.17 A cross-sectional view taken along line XVIII-XVIII. DETAILED DESCRIPTION

[0029] Hereinafter, embodiments are described with reference to the accompanying drawings.

[0030] In each embodiment, elements corresponding to each other in function and / or structure are given the same reference numerals.

[0031] (First embodiment)

[0032] First, refer to Figure 1 A schematic configuration of an electronic device to which an antenna device is applied is described. The electronic device is, for example, an electronic control unit (ECU) mounted on a movable body such as a vehicle. ECU is an abbreviation of an electronic control unit.

[0033] <Electronic Control Unit>

[0034] like Figure 1 As shown, the electronic device 10 includes a circuit board 11. The circuit board 11 has a wiring board provided with wiring on an insulating substrate material and electronic components mounted on the wiring board to form a circuit together with the wiring. The circuit board 11 is accommodated in, for example, a housing or a casing (not shown). In the following, the thickness direction of the circuit board 11 (i.e., the wiring board) is the Z direction. In addition, a direction orthogonal to the Z direction is defined as the X direction, and a direction orthogonal to the Z direction and the X direction is defined as the Y direction.

[0035] Region R1, which is a part of the circuit board 11, provides a wireless communication function. The wireless communication unit 12 is formed in the region R1. Region R1 is a portion surrounded by long and short alternating dotted lines (or single-point dashed lines) in a plan view in the Z direction. Region R1 is a region including a corner of the circuit board 11, which is a substantially rectangular shape in a plan view in the Z direction. Region R1 includes a portion of the side 11a of the circuit board 11 in the Y direction. Hereinafter, the side 11a may also be referred to as the board end 11a. The wireless communication unit 12 includes an antenna device 20 and a feeding circuit (i.e., a communication circuit) described later.

[0036] As described above, the electronic device 10 has a built-in wireless communication unit 12. For example, the electronic device 10 can perform wireless communication with other electronic devices provided in the vehicle. The other electronic devices may be provided outside the housing that accommodates the circuit board 11, or may be accommodated in the same housing as the electronic device 10. The electronic device 10 may be configured to perform wireless communication with the outside of the vehicle.

[0037] In the circuit board 11, the electronic components 13 are mounted in the area R2 to form a circuit, and the area R2 is the rest outside the area R1. The area R2 provides the ability to control the vehicle. In the plan view in the Z direction, the area R2 is larger than the area R1. The processor, memory, etc. (not shown) are installed in the area R2. The memory here is a storage device, or, for example, at least one type of non-temporary tangible storage medium, such as a semiconductor memory, a magnetic medium, an optical medium, etc., for storing or memorizing computer-readable programs, data, etc. The processor includes, for example, at least one of a CPU (central processing unit), a GPU (graphics processing unit), a RISC (reduced instruction set computer)-CPU, etc. as its core.

[0038] The processor performs various processes for realizing the functions according to the program stored in the memory. For example, at least one of the processing results is sent to another electronic device through wireless communication. For example, the processor uses information acquired from another electronic device through wireless communication and performs processing according to the above program. The processor and the memory are provided as a microcomputer / microcontroller as one electronic component, for example. A power supply circuit and the like are also formed in the region R2 of the circuit board 11.

[0039] <Structure of Antenna Device>

[0040] Next, refer to Figure 2 , 3 and 4 describe the structure of the antenna device. Figure 2 It is an exploded perspective view of the antenna device. Figure 3 This is an enlarged plan view of the vicinity of the opposing conductor when viewed from the opposing conductor side. Figure 4 is along Figure 3 A cross-sectional view taken along line IV-IV.

[0041] The antenna device 20 is configured to transmit and / or receive radio waves having a predetermined operating frequency. An example of the operating frequency is 2.44 GHz. The antenna device 20 is configured to be able to transmit and / or receive radio waves in a frequency band used for short-range wireless communication. The operating frequency can be appropriately designed and can be other frequencies than 2.44 GHz (for example, it can be 5 GHz).

[0042] The antenna device 20 of the present embodiment is formed on the circuit board 11. In other words, the antenna device 20 is realized by using the circuit board 11. The antenna device 20 is arranged on the circuit board 11 in the Y direction ( Figure 1 , 2 and 3 to the right) on a side surface.

[0043] like Figures 2 to 4As shown, the antenna device 20 includes a substrate 30, a ground plate 40, an opposing conductor 50, a feed line 60, a short-circuit portion 70, and an intermediate conductor 80. Hereinafter, for convenience, the direction from the ground plate 40 to the opposing conductor 50 is defined as upward (along the positive Z direction), and the direction from the opposing conductor 50 to the ground plate 40 is defined as downward (along the negative Z direction). Figure 3 It is a plan view (a bird's eye view along the negative Z direction), and the Z direction is upward and away from the paper. Figure 4 is along the positive Y direction (equivalent to Figure 3 (from left to right) side view.

[0044] The substrate 30 corresponds to an insulating substrate material constituting the circuit board 11 (i.e., a wiring board). The antenna device 20 is arranged in the region R1 of the substrate 30. The substrate 30 is made of a dielectric material such as a resin. By using the substrate 30, a wavelength shortening effect of the dielectric material can be expected. As the substrate 30, for example, a material made of only resin, or a combination of resin and glass cloth, nonwoven fabric, etc. can be used.

[0045] The facing distance between the ground plate 40 and the relative conductor 50 and the length of the short-circuit portion 70 can be adjusted by adjusting the thickness of the substrate 30. The function of the substrate 30 is to hold the ground plate 40 and the relative conductor 50 in a predetermined positional relationship (i.e., separated from each other). The substrate 30 has a multilayer structure. The substrate 30 of the present embodiment is a laminate formed by laminating three thin plates 30A provided as dielectric materials. The thin plate 30A is not limited to a sheet shape, but may be a film shape.

[0046] The ground plate 40 is a flat conductor made of copper or the like. The plate thickness direction of the substrate 40 is substantially parallel to the Z direction, i.e., the plate thickness direction of the circuit board 11. The direction perpendicular to (orthogonal to) the plate surface of the ground plate 40 is also substantially parallel to the Z direction. Hereinafter, the shape of the ground plate 40 in a plane viewed from the plate thickness direction, i.e., the Z direction, is referred to as a plane shape.

[0047] The ground plate 40 has a size including the entire opposing conductor 50 and the penetration portion 81 (or penetration cutout) described later in a plan view. The ground plate 40 has, for example, a substantially rectangular shape in a plane. The ground plate 40 of the present embodiment is disposed on the lower / bottom surface of the substrate 30. The ground plate 40 is formed by patterning a metal foil disposed on one surface of the thin plate 30A forming the lower surface of the substrate 30. The ground plate 40 is connected to a feed circuit (not shown) to provide a ground potential in the antenna device 20.

[0048] The relative conductor 50 is a plate-shaped conductor made of copper or the like. The relative conductor 50 is a conductor arranged to face / opposite to the ground plane 40 so as to be at a predetermined distance from the ground plane 40 in the Z direction. The relative conductor 50 may be referred to as a patch portion or a radiating element. In a plan view, the entire relative conductor 50 overlaps the ground plane 40. That is, the entire plate surface (lower surface) of the relative conductor 50 faces the ground plane 40 in the Z direction. The relative conductor 50 is arranged to be substantially parallel to the ground plane 40. The relative conductor 50 of the present embodiment is arranged on the upper surface of the substrate 30. The relative conductor 50 is formed by patterning a metal foil arranged on one surface of the thin plate 30A forming the upper surface of the substrate 30. The relative conductor 50 has a flat square shape. As the side portions defining the square, the relative conductor 50 has a side portion substantially parallel to the X direction and a side portion substantially parallel to the Y direction.

[0049] The relative conductor 50 is electrically connected to the feeding circuit via the feeder 60. The feeder 60 of the present embodiment includes a conductor disposed on the upper surface of the substrate 30. Such a conductor may also be referred to as a microstrip line. One end of the feeder 60 is connected to one of the four sides of the relative conductor 50. The connection portion of the feeder 60 on the relative conductor 50 corresponds to a feeding point. The current input from the feeding circuit to the feeder 60 propagates to the relative conductor 50 and excites the relative conductor 50. The power supply method is not limited to the direct power supply method. A feeding method in which the feeder 60 and the relative conductor 50 are electromagnetically coupled may also be adopted.

[0050] The short-circuit portion 70 electrically connects the ground plate 40 and the relative conductor 50, that is, short-circuits the two. The short-circuit portion 70 is a columnar conductor, one end of which is connected to the ground plate 40 and the other end is connected to the relative conductor 50. The short-circuit portion 70 of this embodiment is composed of a via conductor formed on the circuit board 11 (i.e., a wiring board). As described above, the base material 30 (thin plate 30A) has a through hole 31. Then, the short-circuit portion 70 is formed by a conductor set in the through hole 31.

[0051] In a plan view, the short-circuit portion 70 is connected to the basic center of the relative conductor 50. The center of the relative conductor 50 corresponds to the center of gravity of the relative conductor 50. Since the relative conductor 50 of the present embodiment has a flat square shape, the center corresponds to the intersection of two diagonal lines of the relative conductor 50. The number of conductors constituting the short-circuit portion 70 is not particularly limited. The short-circuit portion 70 may be provided as a plurality of conductors connecting the basic center (i.e., the central area) of the relative conductor 50 and the ground plate 40.

[0052] The intermediate conductor 80 is a conductor having the same potential as the ground plate 40 (i.e., ground potential), and is disposed between the ground plate 40 and the opposing conductor 50 in the Z direction. The intermediate conductor 80 of the present embodiment is an inner layer ground disposed inside the substrate of the circuit board 11. The intermediate conductor 80 is electrically connected to the ground plate 40 on the circuit board 11. The connection portion between the intermediate conductor 80 and the ground plate 40 is disposed in at least one of the regions R1 and R2. The intermediate conductor 80 is also formed by patterning a metal foil disposed on the substrate 30 (i.e., the thin plate 30A).

[0053] The intermediate conductor 80 has a penetration portion 81 that penetrates the intermediate conductor 80 in the Z direction. The penetration portion 81 is arranged to overlap the opposing conductor 50 in a plan view (see FIG. Figure 3 The penetration portion 81 may have two parts, namely, a part directly below the opposing conductor 50 and a peripheral part surrounding the part directly below the opposing conductor 50. In a plan view, the intermediate conductor 80 has a predetermined gap between the intermediate conductor 80 and the opposing conductor 50 (see FIG. Figure 3 The intermediate conductor 80 is disposed around or near the opposing conductor 50 so as not to overlap with the opposing conductor 50 in a plan view. Figure 2 and Figure 3 An intermediate conductor 80 is shown surrounding three sides of the opposing conductor 50, separated by distances L1, L2, and L3.

[0054] The penetration portion 81 is configured as a notch ( Figure 2 The penetration portion 81 of the present embodiment is a notch. The penetration portion 81 has a substantially rectangular shape in a plane. Specifically, the penetration portion 81 has a rectangular shape with the X direction as the longitudinal direction and the Y direction as the transverse direction. Three sides of the rectangular penetration portion 81 are defined by the intermediate conductor 80 (specifically, by the three internal vertical surfaces of each intermediate conductor 80), and the remaining side is defined by the plate end portion (side surface) 11a. The intermediate conductor 80 has a substantially C-shaped plane (or a substantially U-shaped plane).

[0055] The number of intermediate conductors 80 disposed between the ground plate 40 and the relative conductor 50 is not particularly limited. At least one conductor 80 may be placed therein. The intermediate conductors 80 may be arranged in multiple stages / layers in the Z direction. The intermediate conductors 80 of the present embodiment are arranged in two stages (i.e., two layers). The configurations of the two intermediate conductors 80 are identical to each other. In a plan view, the intermediate conductors 80 may substantially overlap / match each other.

[0056] <Operation of Antenna Device>

[0057] Next, the operation of the antenna device 20 is described. As described above, the antenna device 20 has a structure in which the ground plate 40 and the opposing conductor 50 facing each other are connected by the short-circuit portion 70. This structure is a so-called mushroom structure, which is the same as the basic structure of a metamaterial. Since the antenna device 20 is an antenna to which the metamaterial technology is applied, it is sometimes called a metamaterial antenna.

[0058] Since the antenna device 20 is designed to operate in the 0th order resonance mode at the desired operating frequency, it is sometimes referred to as a 0th order resonance antenna. In the dispersion characteristics of the metamaterial, the resonance phenomenon at the frequency at which the phase constant β becomes zero (0) is the 0th order resonance. The phase constant β is the imaginary part of the propagation coefficient γ of the wave propagating on the transmission line. The antenna device 20 can satisfactorily transmit and / or receive radio waves in a predetermined frequency band including the frequency at which the 0th order resonance occurs.

[0059] The antenna device 20 operates by LC parallel resonance of the capacitance formed between the ground plate 40 and the opposing conductor 50 and the inductance provided in the short-circuit portion 70. In the antenna device 20, the opposing conductor 50 is short-circuited to the ground plate 40 by the short-circuit portion 70 provided in the central area thereof. The area size of the opposing conductor 50 is the area size that forms the capacitance that parallel resonates with the inductance of the short-circuit portion 70 at a desired frequency (i.e., at an operating frequency). Note that the inductance is determined according to the size of each portion of the short-circuit portion 70 (i.e., for example, the diameter and length in the Z direction).

[0060] Therefore, when power of the operating frequency is supplied, parallel resonance occurs due to the energy exchange between the inductor and the capacitor, thereby generating an electric field perpendicular to the ground plate 40 (and perpendicular to the relative conductor 50) between the ground plate 40 and the relative conductor 50. That is, an electric field is generated in the Z direction. The vertical electric field (perpendicular to the ground plate 40) propagates from the short-circuit portion 70 to the edge of the relative conductor 50, is vertically polarized at the edge of the relative conductor 50, and propagates in space. Note that the vertical polarized wave here refers to a radio wave whose vibration direction of the electric field is perpendicular to the ground plate 40 and the relative conductor 50. In addition, the antenna device 20 receives the vertical polarized wave arriving from the outside of the antenna device 20 through LC parallel resonance.

[0061] The resonant frequency of the 0th order resonance does not depend on the antenna size. Therefore, the length of one side relative to the conductor 50 can be made shorter than 1 / 2 wavelength of the 0th order resonance frequency. For example, even if the length of one side is equal to 1 / 4 wavelength, the 0th order resonance can be generated. It can be made shorter than 1 / 4 wavelength, but in this case, for example, the gain will be reduced.

[0062] <Overview of First Embodiment>

[0063] Figure 5The results of electromagnetic field simulation (reflection characteristics) performed at the same operating frequency in the reference example and the present embodiment are shown. The operating frequency is 2.44 GHz. Figure 5 In the figure, the dotted line represents the result of the reference example, and the solid line represents the result of the present embodiment, that is, the result of the antenna device 20 having the above-mentioned configuration. The antenna device of the reference example is a 0th-order resonant antenna without an intermediate conductor. In the reference example and the present embodiment, the composition of the substrate (i.e., the dielectric constant and thickness) and the diameter of the short-circuit portion are the same as each other. Then, an optimization design is performed according to the size of the relative conductor (i.e., the area size). More specifically, the relative conductor of the reference example has a square shape with one side being 15.64 mm, and the relative conductor of the present embodiment has a square shape with one side being 14.9 mm.

[0064] In a 0th order resonant antenna without an intermediate conductor as in the reference example, if the area size of the ground plane is small, the operation becomes unstable. For example, in a 0th order resonant antenna, in order to improve the reflection characteristics, it is ideal that the ground plane has an infinite size. Therefore, it is preferable to set the length of each side of the planar rectangular ground plane to a length greater than one wavelength. In the reference example, the length of each side is greater than one wavelength. Even considering the size of the ground plane, in an antenna device without an intermediate conductor, the frequency bandwidth, i.e., the bandwidth of the return loss S11 = -10 dB, is narrow, as shown in FIG. Figure 5 Note that when the length of each side of the ground plane is made shorter than one wavelength, Figure 5 Compared with the dotted line shown, the reflection characteristics are deteriorated and the frequency bandwidth is further narrowed.

[0065] On the other hand, according to this embodiment, Figure 5 As shown by the solid line in FIG. 1 , the reflection characteristic can be improved compared with the reference example. The provision of the intermediate conductor 80 increases the frequency bandwidth. Figure 6 As shown in FIG. 1 , a capacitor C2 is additionally formed in the parallel resonance structure formed by the inductor L1 formed by the short-circuit portion 70 and the capacitor C1 between the ground plate 40 and the opposing conductor 50. The capacitor C2 is formed between the intermediate conductor 80 and the opposing conductor 50, and the intermediate conductor 80 and the ground plate 40 have a ground potential together. That is, a parallel resonance structure of the inductor L1 and the capacitor C2 is added. Since the resonance point is formed by the capacitor C2, as shown in FIG. Figure 5 As shown, the frequency bandwidth becomes wider.

[0066] As described above, according to this embodiment, a broadband antenna device 20 can be provided. Due to the broadband, for example, it is not easily affected by reflection from the metal of the housing and switching noise of the power supply circuit formed on the circuit board 11.

[0067] The size of the penetration portion 81, that is, the length in the direction parallel to each side of the opposite conductor 50 is not particularly limited. The penetration portion 81 can be provided to include the opposite conductor 50 at least in a plan view. The capacitor C2 is formed by having a gap between the intermediate conductor 80 and the opposite conductor 50 in a plan view. Since the intermediate conductor 80 has the penetration portion 81 including the opposite conductor 50, the antenna device 20 can have a wide bandwidth.

[0068] In the above configuration, the portion where the ground plate 40 overlaps with the penetration portion 81 in a plan view is basically used as a ground plate (i.e., as grounding). Therefore, the ground plate 40 can be reduced according to the size of the penetration portion 81. By reducing the ground plate 40, the outer shape / size of the antenna device 20 can be reduced. Therefore, it is preferable to set the size of the penetration portion 81 within a range that can reduce the outer shape / size of the antenna device 20, in other words, within a range where the length of each side of the ground plate 40 can be less than one wavelength of the operating frequency. In addition, the size of the penetration portion 81 can be set so that the frequency bandwidth becomes wider at the 0th order resonance frequency (i.e., the operating frequency).

[0069] When performing the above electromagnetic field simulation, Figure 3 As shown, the length of the penetration portion 81 in the X direction is defined as LX, and the length of the penetration portion 81 in the Y direction is defined as LY. In addition, the distance between the opposing conductor 50 and the intermediate conductor 80 in the plan view is defined as L1 and L2 in the X direction, and the distance between the opposing conductor 50 and the intermediate conductor 80 in the plan view is defined as L3 in the Y direction. In addition, the distance between the end surface of the plate (that is, one end of the penetration portion 81) and the opposing conductor 50 in the Y direction is defined as L4. Then, the distances L1 and L2 are set to 6 mm, the distance L3 is set to 2.5 mm, and the distance L4 is set to 3.2 mm.

[0070] In the present embodiment, the length of each side of the (substantially square) opposing conductor 50 is 14.9 mm, which corresponds to about 1 / 4 wavelength of the operating frequency (i.e., 0th order resonant frequency). Therefore, the length LX of the penetration portion 81 in the X direction is 26.9 mm, and the length LY thereof in the Y direction is 20.6 mm. The size of the penetration portion 81 is smaller than 1 / 2 wavelength of the operating frequency in both the X and Y directions. Even if the size of the penetration portion 81 is shorter than 1 / 2 wavelength of the operating frequency in this way, it is possible to Figure 5 The band is widened as shown by the solid line in . Note that the wavelength λε of the radio wave at the operating frequency (i.e., the 0th order resonance frequency) can be obtained by (300 [mm / s] / 244 [GHz]) / square root of the dielectric constant of the substrate 30. In this embodiment, the dielectric constant of the substrate 30 is 4.4. In the configuration including the substrate 30, all wavelengths shown in the embodiment are the above-mentioned wavelength λε.

[0071] (First Modification)

[0072] Figure 7 A first modified example of the antenna device 20 is shown. Figure 7 Corresponds to Figure 3 .exist Figure 7 In the antenna device 20, the distances L1 to L4 and the lengths LX and LY set in the electromagnetic field simulation are applied. Since the intermediate conductor 80 only needs to have a size and shape that can define the penetration portion 81, Figure 7 The ratio of Figure 3 The width of the intermediate conductor 80 is, for example, shorter than 1 / 4 wavelength. The width is, for example, shorter than any one of the distances L1 to L4. The ground plate 40 may be disposed at least in a portion / position overlapping with the penetration portion 81. When the ground plate 40 matches the penetration portion 81, the length of the ground plate 40 in the X direction is 26.9 mm, and the length in the Y direction is 20.6 mm. The ground plate 40 may be aligned (parallel) with the penetration portion 81 and the frame.

[0073] In this way, the size of the ground plate 40 can be made smaller than 1 / 2 wavelength or approximately equal to 1 / 2 wavelength in both the X direction and the Y direction. Even if the size of the ground plate 40 is reduced to a size of approximately 1 / 2 wavelength or less, the narrowing of the frequency bandwidth can be suppressed. Figure 7 In the structure shown, it is also possible to obtain Figure 5 The same effect as the present embodiment shown by the solid line can be achieved. Therefore, the shape / size can be reduced while widening the frequency bandwidth.

[0074] The relationship between the distances L3 and L4 is not limited to the above example. In the present embodiment, the antenna device 20 is arranged in an area including the board end 11a (i.e., the side). That is, the relative conductor 50 is arranged in the vicinity of the board end 11a. Due to this arrangement, the length of the grounding plate 40 located on the board end 11a side of the relative conductor 50 and the length of the grounding plate 40 located on the opposite side of the board end 11a along the Y direction are different. In other words, the arrangement of the grounding plate 40 is uneven and is offset in the Y direction relative to the center of the relative conductor 50. Since the grounding plate 40 located on the board end 11a side is short, the intermediate conductor 80 is not arranged on the board end 11a side relative to the relative conductor 50, and the penetration portion 81 is cut into a notch.

[0075] In this construction, Figure 8As shown, a discontinuous surface 41 is formed at the interface between the plate end 11a (i.e., the circuit board 11) and the outside in the Y direction (i.e., the air). In addition, a discontinuous surface 42 formed by the penetration portion 81 of the intermediate conductor 80 is formed on the side opposite to the discontinuous surface 41. Due to the large difference in dielectric constant, the discontinuous surface 41 is more likely to reflect the electric field than the discontinuous surface 42. When the distance L4 on the side of the plate end 11a is made longer than the distance L3 on the opposite side as shown in this embodiment, the bias of the electric field relative to the X-axis can be suppressed, or the electric field can be made substantially symmetrical about it. By adjusting the distance from the end of the relative conductor 50 toward the penetration portion 81 in this way, the degradation of the reflection characteristics that would otherwise be caused by the asymmetric arrangement of the ground plate 40 relative to the relative conductor 50 can be suppressed.

[0076] The relationship between the lengths L1 and L2 is not limited to the above example. In the X direction, a discontinuous surface formed by the penetration portion 81 of the intermediate conductor 80 is formed on both sides of the opposing conductor 50. Since the reflections on the discontinuous surface are substantially equal, the electric field can be made substantially symmetrical with respect to the Y axis by making the distances L1 and L2 substantially equal to each other as described above.

[0077] The thickness and number of layers of the substrate 30 are not limited to the above examples. The capacitance of the capacitors C1 and C2 and the inductance of the inductor L1 can be adjusted by adjusting the thickness of the substrate 30 (ie, the thin plate 30A).

[0078] (Second embodiment)

[0079] The second embodiment is a modification of the previous embodiment as a basic configuration, and the description of the previous embodiment can be incorporated. In the previous embodiment, a notch is used as the penetration portion 81. Alternatively, a through hole can also be adopted.

[0080] Fig. 9 The antenna device 20 of this embodiment is shown. Fig. 9 Corresponds to Figure 3 The antenna device 20 is formed away from the plate end 11a (i.e., the side). The intermediate conductor 80 has a through hole (rectangular hole) as a penetration portion 81. The penetration portion 81 overlaps at least the opposing conductor 50. The intermediate conductor 80 has a closed rectangular cutout near its center. In a plan view, the intermediate conductor 80 surrounds the opposing conductor 50.

[0081] In the present embodiment, the penetration portion 81 is formed as a substantially square plane. The lengths LX and LY of the penetration portion 81 are substantially equal to each other. As for the distance between the relative conductor 50 and the intermediate conductor 80 in the plan view, the distances L1 and L2 in the X direction are substantially equal to each other. The distances L3 and L4 in the Y direction are also substantially equal to each other. In other words, the distances L1 to L4 are substantially equal to each other. The other configurations are the same as those described in the previous embodiment. Fig. 9It shows bilateral symmetry with respect to the central axis in the X direction, and also shows bilateral symmetry with respect to the central axis in the Y direction (except the feed line 60 ).

[0082] <Overview of Second Embodiment>

[0083] The antenna device 20 of the present embodiment also has the same effects as those of the configuration described in the previous embodiment. For example, even in the configuration using a through hole as the penetration portion 81, the capacitor C2 is formed between the opposing conductor 50 and the intermediate conductor 80 (see Figure 6 ). Therefore, the antenna device 20 having a broadband (ie, a wide frequency bandwidth) can be provided.

[0084] The size of the penetration portion 81 is not particularly limited. Since the portion of the ground plate 40 that overlaps with the penetration portion 81 in a plan view is basically used as a ground plate (i.e., as a ground), the size of the penetration portion 81 can be set within a range that can reduce the outer shape / size of the antenna device 20. In addition, the size of the penetration portion 81 can be set to make the frequency bandwidth wider at the 0th order resonance frequency (i.e., the operating frequency).

[0085] Also in this embodiment, when the size of the penetration portion 81, that is, the length LX and LY of the penetration portion 81 are shorter than 1 / 2 wavelength of the operating frequency, the band can be widened. Even if the size of the ground plate 40 is reduced to about 1 / 2 wavelength or less, the narrowing of the frequency bandwidth can be suppressed. Therefore, the shape / size can be reduced while widening the frequency bandwidth.

[0086] The relationship between the distances L1 and L2 and the relationship between the distances L3 and L4 are not limited to the above examples. The discontinuous surface formed by the penetration portion 81 of the intermediate conductor 80 is located / set on both sides of the relative conductor 50 in the X direction. Since the reflection on the discontinuous surface is substantially equal, as described above, the electric field can be substantially symmetrical with respect to the Y axis by making the distances L1 and L2 substantially equal to each other. Similarly, by making the distances L3 and L4 substantially equal to each other, the electric field can be substantially symmetrical with respect to the X axis.

[0087] The distance L1 (L2) and the distance L3 (L4) may be different from each other. In the present embodiment, since the distances L1 to L4 are substantially equal to each other, the conductor 50 has directivity in all directions from the central area toward the edge.

[0088] (Third Embodiment)

[0089] The third embodiment is a modification of the previous embodiment as a basic configuration, and the description of the previous embodiment can be incorporated. In the previous embodiment, the opposing conductor 50 has a flat square shape. Alternatively, a slit may be provided in the opposing conductor 50 that otherwise has a flat square shape.

[0090] Fig.10 The antenna device 20 of this embodiment is shown. Fig.10 Corresponds to Figure 3 As in the configuration described in the first embodiment, the antenna device 20 is formed in the region including the board end portion 11a. At least one slit 51 is formed in the opposing conductor 50. The slit 51 has a predetermined depth in the Z direction and opens to one of the end faces (side faces) of the opposing conductor 50.

[0091] The slits 51 of this embodiment penetrate the opposing conductor 50 in the Z direction. The opposing conductor 50 has two slits 51 (in Fig.10 The two slits 51 are provided so that the relative conductor 50 has double symmetry about the Z axis. The two slits 51 are provided so as to sandwich the short-circuit portion 70, in other words, to constrain the center of the relative conductor 50 in the Y direction in a plan view. One of the slits 51 is opened on the side of the relative conductor 50 on the plate end portion 11a side, and the other slit 51 is opened on the side on the opposite side. The slits 51 are opened on the two sides of the unconnected feeder 60 facing each other.

[0092] The extension length and width of the two slits 51 are equal to each other. The slit 51 divides the relative conductor 50 into a first relative portion 50a and a second relative portion 50b. The first relative portion 50a and the second relative portion 50b have the same shape and area size. The part sandwiched by the two slits 51 forms a connecting portion 50c connecting the first relative portion 50a and the second relative portion 50b. In other words, the relative conductor 50 has a first relative portion 50a, a second relative portion 50b and a connecting portion 50c. The extension length of the slit 51 in the Y direction is longer than the length of the connecting portion 50c in the Y direction, and the width of the slit 51 is shorter than the width of the first relative portion 50a and the second relative portion 50b. The relative conductor 50 is formed into a flat, substantially square shape, wherein the slit 51 is cut and removed from the square.

[0093] Fig.11 is an equivalent circuit diagram of the antenna device 20. Fig.11 , for the sake of convenience, some circuit elements, for example, an inductor included in the relative conductor 50, are omitted. By providing the slits 51, a capacitor C3 is formed between the first relative portion 50a and the second relative portion 50b. The capacitor C3 is a parallel circuit (equivalent capacitor) of capacitors formed in each of the two slits 51. The capacitor C3 is connected in series with another parallel circuit formed by the capacitors C1 and C2.

[0094] <Overview of Third Embodiment>

[0095] Fig.12The results of the electromagnetic field simulation (reflection characteristics) are shown. The basic conditions of the electromagnetic field simulation are the same as those of the previous embodiment. More specifically, the operating frequency, the composition of the substrate (dielectric constant and thickness), and the diameter of the short-circuit portion are the same as those of the previous embodiment. In addition, the size of the penetration portion 81, that is, the lengths LX and LY are also the same as those of the previous embodiment. Then, the optimization design is performed based on the size of the relative conductor 50 and the size of the slit 51. The size of the relative conductor 50 refers to the size of the area facing the ground plate 40 and the relative conductor 50. The size of the slit 51 refers to the length and width of the slit. As described above, the slit 51 in the third embodiment can be a pair of slits (a left slit 51 and a right slit 51).

[0096] More specifically, each side of the opposing conductor 50 is set to 13 mm. In addition, the length of the left slit 51 in the extending direction is set to 5.6 mm, and the width thereof is set to 1.75 mm. For comparison, Fig.12 Shows Figure 5 An example of a previous embodiment is shown with solid lines (ie without slits). Fig.12 An example of “no slit” is shown by a two-dot chain line, and an example of the present embodiment (with a left slit and a right slit) is shown by a solid line.

[0097] The antenna device 20 of the present embodiment further includes an intermediate conductor 80, which forms a capacitor C2. Fig.12 As shown, the frequency bandwidth is widened.

[0098] In this embodiment, by providing the slit 51 in the opposing conductor 50, the area size of the opposing conductor 50 is reduced, thereby reducing the capacitance of the capacitor C1. On the other hand, the slit 51 connects the capacitor C3 in series with the capacitor C1. In this way, the number of variables that determine the total capacitance increases. The capacitance of the capacitor C3 can be set, for example, by the extension length and / or width of the slit 51.

[0099] By providing the capacitor C3 in this manner, the degree of freedom in designing the antenna device 20 (ie, the 0th order resonant antenna) is improved. Fig.12 As shown, the reflection characteristics can be improved compared to the case where there is no slit. The frequency band can also be adjusted (ie, moved).

[0100] Furthermore, the opposing conductor 50 can have a smaller body size while having the same or higher characteristics than a configuration without the slit 51. By reducing the size of, for example, the circuit board 11, the design freedom of the opposing conductor 50 can be improved. More specifically, it can fit into a narrower / smaller space.

[0101] The shape, size, arrangement and number of the slits 51 are not limited to the above examples. For example, the positions of the two slits 51 may be staggered in the X direction (i.e., not on a virtual straight line). In addition, the slits 51 may be arranged to open on the side along the X direction. Only one slit 51 may be arranged, or three or more slits 51 may be arranged. The slits 51 are not limited to a straight line shape. For example, a slit 51 having a substantially L-shaped flat shape may be adopted. As described above, if the slits 51 are arranged so as to have a double symmetry relative to the conductor 50, the bias of the electric field distribution may be suppressed.

[0102] Although an example is shown in which the slit 51 penetrates the opposing conductor 50 in the Z direction, the present invention is not limited to this example. The slit 51 in the opposing conductor 50 may have a half depth of the conductor 50, that is, may have a groove shape. Even in this structure, the capacitor C3 is formed between the opposing surfaces of the first opposing portion 50a and the second opposing portion 50b.

[0103] Although the example in which the slit 51 is combined with the configuration described in the first embodiment has been shown, the present invention is not limited to this example. The configuration of this embodiment can also be combined with the configuration described in the second embodiment.

[0104] (Fourth embodiment)

[0105] The fourth embodiment is a modification of the previous embodiment as a basic configuration, and the description of the previous embodiment can be incorporated. In addition to the configuration described in the previous embodiment, a shielding wall can be provided.

[0106] Fig.13 and Fig.14 The antenna device 20 of this embodiment is shown. Fig.13 Corresponds to Fig.10 . Fig.14 is along Fig.13 The antenna device 20 further includes a shielding wall 90. The structure other than the shielding wall 90 is the third embodiment (see Fig.10 ) described in the structure and modification examples (see Figure 7 )A combination of the intermediate conductor 80 described.

[0107] The shielding wall 90 is composed of a plurality of columnar portions 91. The columnar portion 91 is connected to the intermediate conductor 80 and extends in the Z direction. The columnar portion 91 is a columnar conductor connected to the intermediate conductor 80 and set to a ground potential. The plurality of columnar portions 91 act as a wall to block / interrupt radio waves by being arranged at intervals of less than 1 / 2 wavelength of the operating frequency so that the radio waves do not leak from between the columnar portions 91. A plurality of columnar portions 91 are arranged along the inner edge of the limiting penetration portion 81 of the intermediate conductor 80. In a structure in which the intermediate conductor 80 is arranged in multiple layers (multiple stages), the columnar portion 91 is connected to at least one intermediate conductor 80.

[0108] The columnar portion 91 has a conductor disposed in a through hole 32 that penetrates at least one layer of the thin plate 30A. The columnar portion 91 is, for example, configured as a via conductor or a through-hole conductor. The through hole 32 can be formed in a unit of the thin plate 30A (i.e., it can be formed from plate 30A to plate 30A). The through hole 32 can also be formed on a substrate 30 made into a stacked thin plate 30A. In the present embodiment, the through hole 32 penetrates the substrate 30, and each columnar portion 91 extends from the ground plate 40 to the upper surface of the substrate 30. The columnar portion 91 is connected to the ground plate 40.

[0109] like Fig.13 As shown, three sides of the rectangular penetration portion 81 are formed by the intermediate conductor 80, and the remaining side is formed by the plate end 11a. The intermediate conductor 80 is a narrow frame with a flat basic C shape (i.e., a basic U shape). A plurality of columnar portions 91 are arranged along the frame of the intermediate conductor 80. The columnar portions 91 are arranged on both sides of the intermediate conductor 80 except for the side toward which the feeder 60 extends. The shielding wall 90 has a basic L shape in a plan view. With respect to the relative conductor 50, the shielding wall 90 is arranged on the side opposite to the feeder 60 in the X direction. In addition, the shielding wall 90 is arranged on the side opposite to the plate end 11a in the Y direction.

[0110] Note that, in the present embodiment, the base material 30 is formed by laminating five thin plates 30A, and the intermediate conductors 80 are provided in four layers. The intermediate conductors 80 of each layer have the same configuration as each other.

[0111] <Overview of Fourth Embodiment>

[0112] According to the present embodiment, the shielding wall 90 can block / interrupt energy transmitted from the antenna device 20 to the region R2 of the circuit board 11. In addition, the shielding wall 90 can block / interrupt energy entering the antenna device 20 from the circuit formed in the region R2 of the circuit board 11. Since the shielding wall 90 is provided on the outside of the penetration portion 81, the antenna device 20 can obtain the same effect as the configuration described in the previous embodiment even with the shielding wall 90. For example, the frequency bandwidth can be widened.

[0113] The arrangement of the shielding wall 90 is not limited to the above example. For example, it can be arranged only between two intermediate conductors 80. In the present embodiment, the shielding wall 90 extends from the ground plate 40 to the upper surface of the substrate 30. In other words, the shielding wall 90 is connected to the ground plate 40 and all the intermediate conductors 80 arranged thereon. Therefore, the energy transmitted through the circuit board 11 can be effectively interrupted.

[0114] An example is shown above in which the shielding wall 90 is provided on both sides of the intermediate conductor 80 except for one side toward which the feed line 60 extends. However, the present invention is not limited thereto. The shielding wall 90 may be provided only on one side thereof.

[0115] The above shows an example where the ground plate 40 extends to the outside of the intermediate conductor 80. However, the present invention is not limited thereto. Figure 7 The number of laminated sheets 30A constituting the base material 30 and the number of intermediate conductors 80 are not limited to the above-described examples.

[0116] The shielding wall 90 can be combined with each of the configurations described in the previous embodiments. An example is shown above in which the shielding wall 90 is provided in the antenna device 20 in which the relative conductor 50 has the slit 51. However, the present invention is not limited thereto. The shielding wall 90 can be provided in the antenna device 20 in which the relative conductor 50 is not provided with the slit 51.

[0117] As in Fig.15 and 16 In the illustrated modification, the shielding wall 90 may be provided on the antenna device 20 located away from the board end portion 11 a . Fig.15 Corresponds to Fig. 9 . Fig.16 is along Fig.15 The cross-sectional view taken along the line XVI-XVI of FIG. The intermediate conductor 80 is a frame body formed into a rectangular ring shape. A plurality of columnar portions 91 are provided on three sides of the intermediate conductor 80 except for one side toward which the feeder 60 extends. The shielding wall 90 has a substantially C-shape (ie, a substantially U-shape) in a plan view.

[0118] As in Fig.17 and Fig.18 In the second modification shown, a part of the shielding wall 90 may be provided on the provision surface of the opposing conductor 50 . Fig.17 Corresponds to Fig.15 . Fig.18 is along Fig.17 The shield wall 90 is a cross-sectional view taken along the line XVIII-XVIII. In addition to the columnar portion 91, the shield wall 90 also has a surface conductor 92 provided on the upper surface of the substrate 30. Similar to the counter conductor 50, the surface conductor 92 is formed by patterning / cutting a metal foil. The structure other than the surface conductor 92 is similar to Fig.15 The variations shown are the same.

[0119] In a plan view, the surface conductor 92 is substantially matched with the intermediate conductor 80. The surface conductor 92 has a penetration portion 93 that is substantially matched with the penetration portion 81 in a plan view. The penetration portion 93 penetrates the surface conductor 92 in the Z direction. The penetration portion 93 is a conductor-free area defined by the surface conductor 92. The surface conductor 92 also has a penetration slot 94. The penetration slot 94 is provided to avoid / bypass the feed line 60 and penetrate the surface conductor 92 in the Z direction. The penetration slot 94 can also be referred to as a gap between the surface conductors 92. The penetration slot 94 is connected to the penetration portion 93. The surface conductor 92 has a flat, substantially C-shaped shape. The penetration slot 94 and the surface conductor 92 are substantially matched with the intermediate conductor 80 in a plan view.

[0120] The shielding wall 90 may be provided to surround the opposing conductor 50. For example, Fig.15 or Fig.17 In the illustrated configuration, a plurality of columnar portions 91 may be provided on all sides of the center conductor 80, including the side to which the feed line 60 extends.

[0121] (Other embodiments)

[0122] The contents disclosed in this specification, drawings, etc. are not limited to the exemplary embodiments. The present disclosure includes exemplary embodiments and modifications made by those skilled in the art based on the embodiments. For example, the present disclosure is not limited to the combination of parts and / or elements shown in the embodiments. The present disclosure can be implemented in various combinations. The present disclosure may have additional parts added to the embodiments. The present disclosure covers the omission of parts and / or elements of the embodiments. The present invention covers the replacement or combination of parts and elements between one embodiment and another embodiment. The technical scope of the present disclosure is not limited to the description of the embodiments. It is understood that the description of the claims shows the technical scope of the disclosure, and further includes the meaning equivalent to the description of the claims and all modifications within the scope.

[0123] The contents disclosed in the specification, drawings, etc. are not limited by the description of the claims. The contents disclosed in the specification, drawings, etc. cover the technical ideas described in the claims, and further extend to technical ideas of a wider variety than the technical ideas of the claims. Therefore, various technical ideas can be extracted from the contents disclosed in this specification, drawings, etc., without being limited to the description of the claims.

[0124] Although an example in which the antenna device 20 is provided on the circuit board 11 has been shown, the present invention is not limited thereto. Although an example in which the antenna device 20 includes the substrate 30 has been shown, the present invention is not limited thereto. The antenna device 20 may include at least the intermediate conductor 80 having the ground plate 40, the opposing conductor 50, the short-circuit portion 70, and the penetration portion 81.

[0125] The shapes of the ground plate 40 and the opposing conductor 50 in a plan view are not limited to the above examples. The shapes of the ground plate 40 and the opposing conductor 50 may be substantially polygonal in addition to being rectangular or substantially circular. The shape of the intermediate conductor 80 in a plan view is not limited to the above examples. For example, the shape of the intermediate conductor 80 may be substantially circular. The shape of the short-circuit portion 70 is not limited to being circular / ring-shaped. .

Claims

1. An antenna device, comprising: A grounding plate providing ground potential; an opposing conductor (50) spaced apart from the ground plate by a predetermined distance in a plate thickness direction of the ground plate, wherein the opposing conductor is configured to be connected to a feeder line (60); a short-circuit portion (70) electrically connecting the opposing conductor and the ground plate, wherein the antenna device operates in a 0th order resonance mode by using LC parallel resonance of a capacitance formed between the ground plate and the opposing conductor and an inductance provided in the short-circuit portion; and an intermediate conductor (80) having the same potential as the ground plate and located between the ground plate and the opposing conductor in the plate thickness direction, wherein the intermediate conductor at least partially defines a penetration portion (81) penetrating the intermediate conductor and including the opposing conductor in a plan view in the plate thickness direction, wherein The length of one side of the opposing conductor (50) is shorter than 1 / 2 wavelength of the 0th order resonance frequency.

2. The antenna device according to claim 1, further comprising: A substrate (30) comprising a dielectric, wherein The ground plate, the counter conductor, and the intermediate conductor are provided at different positions of the base material in terms of height in the plate thickness direction.

3. The antenna device according to claim 2, wherein The ground plate, the opposing conductor, the short-circuit portion, and the intermediate conductor are part of the base material in the plan view and are arranged in a region (R1) including a plate end portion (11a), and The penetration portion is a notch defined by the intermediate conductor and the plate end portion.

4. The antenna device according to claim 3, wherein In a direction orthogonal to the plate thickness direction, the intermediate conductor is disposed on one side relative to the opposing conductor, and the plate end portion is positioned on a side opposite to the intermediate conductor, and In the one direction, a distance from the opposing conductor to the plate end is longer than a distance from the opposing conductor to the intermediate conductor.

5. The antenna device according to claim 1 or 2, wherein The penetration portion is a through hole surrounded by the intermediate conductor.

6. The antenna device according to claim 1 or 2, wherein The opposing conductor has a predetermined depth in the plate thickness direction and has a slit (51) opened at a side surface of the opposing conductor.

7. An antenna device, comprising: A grounding plate providing ground potential; an opposing conductor (50) spaced apart from the ground plate by a predetermined distance in a plate thickness direction of the ground plate, wherein the opposing conductor is configured to be connected to a feeder line (60); a short-circuit portion (70) electrically connecting the opposing conductor and the ground plate; and an intermediate conductor (80) having the same potential as the ground plate and located between the ground plate and the opposing conductor in the plate thickness direction, wherein The intermediate conductor at least partially defines a penetration portion (81) penetrating the intermediate conductor and including the opposing conductor in a plan view in the plate thickness direction, and The penetration portion has a rectangular shape in the plan view, and a length in a direction along each side of the rectangle is less than or equal to a half wavelength of an operating frequency.

8. An antenna device, comprising: A ground plate (40); a first dielectric plate located above the ground plate (40); a first intermediate conductor located above the first dielectric plate; a second dielectric plate located above the first intermediate conductor; a second intermediate conductor located above the second dielectric plate; a third dielectric plate located above the second intermediate conductor; an opposing conductor (50) located above the third dielectric plate; and a short-circuit portion (70) electrically connecting the ground plate (40), the intermediate conductor and the counter conductor (50), The first intermediate conductor includes a first penetration portion, and the first penetration portion is defined as a notch or a through hole in the first intermediate conductor. wherein the second intermediate conductor comprises a second penetration portion substantially identical to the first penetration portion, The size and position of the relative conductor (50) are set so that in a plan view, the periphery of the relative conductor (50) is completely surrounded by the periphery of the first dielectric plate, the periphery of the second dielectric plate and the periphery of the third dielectric plate: wherein the short-circuit portion (70) vertically passes through the first penetration portion and the second penetration portion, The first penetration portion of the first intermediate conductor penetrates the intermediate conductor in the plate thickness direction. The first penetration portion is provided to surround the opposing conductor (50) in a plan view along the plate thickness direction.

9. The antenna device according to claim 8, wherein: In floor plan: The first penetration portion is a rectangular notch starting at the front edge of the first intermediate conductor; The opposing conductor (50) is substantially square; and The short-circuit portion (70) is substantially circular and is located substantially at the center of the opposing conductor (50).

10. The antenna device according to claim 8, wherein: In floor plan: The first penetration portion is a substantially rectangular through hole such that a periphery of the first penetration portion is completely surrounded by the periphery of the first dielectric plate, the periphery of the second dielectric plate, and the periphery of the third dielectric plate; The opposing conductor (50) is substantially square; and The short-circuit portion (70) is substantially circular and is located substantially at the center of the opposing conductor (50).

11. The antenna device according to claim 8, wherein: In floor plan: The first penetration portion is a rectangular notch starting at the front edge of the first intermediate conductor; The relative conductor (50) includes a left slit opening backward and a right slit opening forward; The left slit is a substantially mirror image of the right slit relative to a left-right axis passing through the short-circuit portion (70), The short-circuit portion (70) is located between the left slit and the right slit, and The short-circuit portion (70) is substantially circular and is located substantially at the center of the opposing conductor (50).

12. The antenna device according to claim 8, further comprising: a shielding wall (90) including a columnar portion (91) electrically connecting the intermediate conductor to the ground plate (40), Wherein, in a plan view, the opposing conductor (50) does not overlap with any of the intermediate conductors.

13. An antenna device, comprising: A grounding plate providing ground potential; an opposing conductor (50) spaced apart from the ground plate by a predetermined distance in a plate thickness direction of the ground plate, wherein the opposing conductor is configured to be connected to a feeder line (60); a short-circuit portion (70) electrically connecting the opposing conductor and the ground plate; an intermediate conductor (80) having the same potential as the ground plate and located between the ground plate and the opposing conductor in the plate thickness direction; as well as A substrate (30) comprising a dielectric, wherein The intermediate conductor at least partially defines a penetration portion (81) which penetrates the intermediate conductor and includes the opposing conductor in a plan view in the plate thickness direction, The ground plate, the counter conductor and the intermediate conductor are arranged at different positions of the substrate in terms of height in the thickness direction. The ground plate, the opposing conductor, the short-circuit portion, and the intermediate conductor are part of the base material in the plan view and are arranged in a region (R1) including a plate end portion (11a), The penetration portion is a notch defined by the intermediate conductor and the plate end, In a direction orthogonal to the plate thickness direction, the intermediate conductor is disposed on one side relative to the opposing conductor, and the plate end portion is positioned on a side opposite to the intermediate conductor, and In the one direction, a distance from the opposing conductor to the plate end is longer than a distance from the opposing conductor to the intermediate conductor.

14. The antenna device according to claim 13, further comprising: a feed line (60) electrically connected to the opposing conductors, wherein The feed line extends from the opposing conductor in a direction orthogonal to the one direction in the plan view.

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