Antenna device

Abstract

This invention relates to an antenna device. It comprises: a base plate (11), which is a flat conductor component; a counter conductor plate (13), which is a flat conductor component disposed at a predetermined interval from the base plate (11) and electrically connected to a power supply line (15); and a plurality of short-circuit pins (14) for electrically connecting the counter conductor plate (13) to the base plate (11), one end of the plurality of short-circuit pins (14) extending to a plane including the counter conductor plate, i.e., the conductor plate plane, and the other end extending to a plane including the base plate, i.e., the base plate plane, and one or more of the plurality of short-circuit pins (14) connecting the counter conductor plate (13) to the base plate (11).

Description

[0001] Cross-references to related applications

[0002] This application is based on Japanese Patent Application No. 2020-104775, filed on June 17, 2020, the contents of which are incorporated herein by reference in their entirety. Technical Field

[0003] This invention relates to antenna devices, and more particularly to techniques for lowering the altitude and adjusting the polarization characteristics of two polarized waves. Background Technology

[0004] Patent Document 1 discloses an antenna that transmits and receives two radio waves with different polarization planes. The antenna disclosed in Patent Document 1 uses a microstrip antenna to form zenith directivity and a monopole antenna for linearly polarized waves to form horizontal directivity.

[0005] In addition, as an antenna device utilizing zero-order resonance, there exists an antenna device having the following components: a flat base plate that is connected to the external conductor of a power supply cable and functions as a ground; a flat conductor plate that is configured to face the base plate and has a power supply point at any position; and a short-circuit section that electrically connects the base plate and the conductor plate (e.g., Patent Document 2).

[0006] Patent Document 1: Japanese Patent Application Publication No. 2005-20301

[0007] Patent Document 2: Japanese Patent Application Publication No. 2018-61137

[0008] For reasons such as optimizing communication quality, there are situations where it is desirable to adjust the gain ratio of intersecting polarized waves. However, in the antenna disclosed in Patent Document 1, adjusting the polarization ratio requires adjusting the antenna length. Therefore, it is difficult to adjust the polarization ratio in the antenna disclosed in Patent Document 1. Furthermore, the polarization ratio is an example of polarization characteristics. In polarization characteristics, in addition to the polarization ratio, there is also the relative direction of the polarization planes.

[0009] Furthermore, the antenna disclosed in Patent Document 1 features a monopole antenna for use as a linearly polarized wave antenna. Since a linearly polarized wave antenna requires approximately 1 / 4 wavelength in length, it is difficult to reduce its height.

[0010] The antenna device disclosed in Patent Document 2 is a low-profile antenna device. However, directly following the structure disclosed in Patent Document 2, it can only radiate vertically polarized waves along a plane parallel to the conductor plate and the base plate, and cannot radiate two radio waves with different polarization planes. Therefore, the antenna device disclosed in Patent Document 2 cannot directly adjust the polarization characteristics of two radio waves with different polarization planes. Summary of the Invention

[0011] This disclosure is made based on this situation, and its purpose is to provide an antenna device capable of low altitude and adjusting the polarization characteristics of two radio waves with different polarization planes.

[0012] The aforementioned objectives are achieved through a combination of features described in the independent technical solutions. Furthermore, dependent technical solutions provide more advantageous specific examples. The reference numerals within parentheses in the claims indicate the correspondence between specific units described in the embodiments described below as an example, and are not intended to limit the scope of the disclosed technology.

[0013] One disclosure for achieving the above objective is an antenna device comprising:

[0014] The base plate is a flat conductor component;

[0015] Opposing conductor plates are flat conductor components arranged at predetermined intervals from the base plate and electrically connected to the power supply lines; and

[0016] Multiple short-circuit pins are used to electrically connect the opposing conductor plate to the base plate.

[0017] Multiple short-circuit pins extend one end to the conductor plate plane and the other end to the base plate plane, wherein the conductor plate plane is a plane that includes the opposing conductor plate and the base plate plane is a plane that includes the base plate.

[0018] One or more of the short-circuit pins connect the opposing conductor plate to the base plate.

[0019] The antenna, which connects the base plate to the opposing conductor plate by a short-circuit pin and supplies power to the opposing conductor plate, is, as also described in Patent Document 2, a low-altitude zero-order resonant antenna capable of radiating radio waves with a polarization plane perpendicular to the base plate and the opposing conductor plate.

[0020] For a zero-order resonant antenna, the radiation characteristics in the direction perpendicular to the opposing conductor plate change when the connection position of the short-circuit pin relative to the opposing conductor plate changes. This antenna device has multiple short-circuit pins. The relative positions of these multiple short-circuit pins with respect to the opposing conductor plate are naturally different. Therefore, by selecting the short-circuit pin that actually connects the opposing conductor plate to the base plate from among the multiple short-circuit pins, and by using one or more of these short-circuit pins to actually connect the opposing conductor plate to the base plate, the radiation characteristics in the direction perpendicular to the opposing conductor plate can be adjusted. Attached Figure Description

[0021] Figure 1 This is a three-dimensional view showing the structure of the antenna device 10.

[0022] Figure 2 This is a top view of antenna device 10.

[0023] Figure 3 This is an internal view of the antenna device 10.

[0024] Figure 4 yes Figure 2 Sectional view along line IV-IV.

[0025] Figure 5 This is a current diagram showing the situation after short-circuiting the 14A short-circuit pin.

[0026] Figure 6 This is a current diagram showing the situation after short-circuiting pin 14C.

[0027] Figure 7 This is a top view of the antenna device 210 according to the second embodiment.

[0028] Figure 8 This is a top view of the antenna device 310 according to the third embodiment.

[0029] Figure 9 This is an inner view of the antenna device 410 according to the fourth embodiment. Detailed Implementation

[0030] The embodiments will now be described with reference to the accompanying drawings. Figure 1 This is a perspective view showing the structure of the antenna device 10 according to this embodiment. Additionally, Figure 2 This is a top view of the antenna device 10. The antenna device 10 includes a base plate 11, a support plate 12, an opposing conductor plate 13, and multiple short-circuit pins 14.

[0031] The base plate 11 is a plate-shaped conductor component made of a conductor such as copper. The base plate 11 is disposed along the lower side of the support plate 12. The plate shape here may also include a thin film such as metal foil. That is, the base plate 11 may also be formed by electroplating or other methods to create a pattern on the surface of a resin board such as a printed wiring board. This base plate 11 is electrically connected to the outer conductor of the coaxial cable, providing ground potential (in other words, grounding potential). Furthermore, unless otherwise specified below, connection means electrical connection.

[0032] The base plate 11 is rectangular when viewed from above. However, the shape of the base plate 11 is not limited to a rectangle. The base plate 11 is preferably linearly symmetrical about each of two mutually orthogonal straight lines (hereinafter, a two-way linearly symmetrical shape). A two-way linearly symmetrical shape is a figure that is symmetrical about a certain straight line as an axis of symmetry and is also linearly symmetrical about other straight lines orthogonal to that line. For example, ellipses, rectangles, circles, squares, regular hexagons, regular octagons, rhombuses, etc., are equivalent to two-way linearly symmetrical shapes. The base plate 11 is preferably formed to be larger than a circle with a diameter equal to one wavelength.

[0033] Figure 1 The X-axis represents the direction of the long side of the base plate 11, the Y-axis represents the direction of the short side of the base plate 11, and the Z-axis represents the axis perpendicular to the XY plane. One example of the antenna device 10's mounting orientation is on the roof of a vehicle with the Z-axis pointing vertically. Alternatively, the antenna device 10 can be mounted on the side of the vehicle, such that the XY plane runs along the side of the vehicle.

[0034] The support plate 12 is a rectangular flat plate component. The support plate 12 serves to separate the base plate 11 and the opposing conductor plate 13 at a predetermined interval, allowing them to be arranged opposite each other. Viewed from above, the support plate 12 is approximately the same size as the base plate 11. The support plate 12 is implemented using a dielectric material having a predetermined relative permittivity. For example, the support plate 12 can be implemented using a printed circuit board with a matrix material such as glass epoxy resin. Here, as an example, glass epoxy resin with a relative permittivity of 4.3 is used to implement the support plate 12.

[0035] By adjusting the thickness of the support plate 12, the distance between the opposing conductor plate 13 and the base plate 11 can be adjusted, as can the length of the short-circuit pin 14. When the distance between the opposing conductor plate 13 and the base plate 11, and the length of the short-circuit pin 14, change, as will be described later, the frequency of the radio waves transmitted and received by the antenna device 10 changes. The specific value of the thickness of the support plate 12 is appropriately determined through simulation and experimentation, so that the frequency of the radio waves transmitted and received by the antenna device 10 is the desired frequency. When the frequency of the radio waves transmitted and received by the antenna device 10 is 2.45 GHz, the thickness of the support plate 12 is, for example, about 1 to 3 mm. This thickness is much shorter than 1 / 10 of the wavelength of the radio waves transmitted and received by the antenna device 10.

[0036] Furthermore, in this embodiment, a structure is adopted in which resin, serving as a support plate 12, is filled between the base plate 11 and the opposing conductor plate 13, but it is not limited to this. The space between the base plate 11 and the opposing conductor plate 13 may also be hollow or a vacuum. Furthermore, resin and space may be combined.

[0037] The opposing conductor plate 13 is a plate-shaped conductor component made of a conductor such as copper. As mentioned above, the plate shape here may also include a thin film such as copper foil. The opposing conductor plate 13 is positioned opposite the base plate 11 across the support plate 12. The opposing conductor plate 13 may also be patterned on the surface of a resin plate such as a printed wiring board, similar to the base plate 11. Furthermore, the parallelism here is not limited to perfect parallelism. It may also be tilted by a few degrees to about ten degrees. That is, it may also include a generally parallel state (the so-called approximately parallel state).

[0038] By arranging the opposing conductor plate 13 and the base plate 11 opposite each other, an electrostatic capacitance is formed corresponding to the area of ​​the opposing conductor plate 13 and the spacing between the opposing conductor plate 13 and the base plate 11. The opposing conductor plate 13 is formed to have the inductance of the short-circuit pin 14 and the electrostatic capacitance that resonates in parallel at a specified target frequency. The target frequency refers to the frequency of the object being transmitted or received.

[0039] The area of ​​the opposing conductor plate 13 can be appropriately designed to provide the desired electrostatic capacitance (and thus operate at the target frequency). For example, the opposing conductor plate 13 can be formed as a square with one side electrically 12 mm. When considering the wavelength shortening effect of the support plate 12, the length of one side of the opposing conductor plate 13, 12 mm, is electrically equivalent to 0.2λ. Of course, the length of one side of the opposing conductor plate 13 can be appropriately changed.

[0040] Furthermore, as an example, the opposing conductor plate 13 is square, but in other structures, its planar shape can be circular, octagonal, hexagonal, etc. Additionally, the opposing conductor plate 13 can also be rectangular, elongated elliptical, etc. Preferably, the opposing conductor plate 13 has a bidirectional linear symmetry shape. More preferably, the opposing conductor plate 13 is a point-symmetric shape such as a circle, square, rectangle, parallelogram, etc.

[0041] Furthermore, gaps can be provided in the opposing conductor plate 13, or the corners can be chamfered. The edges of the opposing conductor plate 13 can also be partially or entirely formed into a zigzag shape. In the bidirectional linearly symmetrical shape, there are also shapes with tiny (about a few millimeters) unevenness on its edges. Unevenness on the edges of the opposing conductor plate 13 that does not affect the operation can be ignored. The technical concept for the planar shape of this opposing conductor plate 13 is the same for the base plate 11 described above.

[0042] A power supply line 15 is connected to the opposing conductor plate 13. In this embodiment, the power supply line 15 is connected to the opposing conductor plate 13 at a position that passes through the center of the opposing conductor plate 13 and divides the opposing conductor plate 13 in half. Figure 2 In the diagram, lines Lx and Ly pass through the center of the opposing conductor plate 13 and divide it into two halves. The intersection of these two lines, Lx and Ly, is the center of the opposing conductor plate 13.

[0043] Furthermore, the position where the power supply line 15 is connected to the opposing conductor plate 13 can be set at a position that matches the input and output impedance relative to the opposing conductor plate 13. The position where the power supply line 15 is connected to the opposing conductor plate 13 can be, for example, the edge or the central area of ​​the opposing conductor plate 13.

[0044] In addition to the direct coupling power supply method used in this embodiment, various other methods, such as electromagnetic coupling, can be used as the method for supplying power to the opposing conductor plate 13. Electromagnetic coupling is a power supply method that utilizes the electromagnetic coupling between a microstrip line or similar device used for power supply and the opposing conductor plate 13.

[0045] The opposing conductor plate 13 is positioned opposite the base plate 11 with one set of opposite sides parallel to the X-axis and the other set of opposite sides parallel to the Y-axis. In this embodiment, the opposing conductor plate 13 is configured such that the center of the base plate 11 and the center of the opposing conductor plate 13 overlap when viewed from above.

[0046] The short-circuit pin 14 is a conductive component that connects the base plate 11 to the opposing conductor plate 13. For example, the short-circuit pin 14 can be implemented using a through hole provided in the printed circuit board that serves as the support plate 12. The short-circuit pin 14 can also be implemented using a conductive pin. By adjusting the length and diameter of the short-circuit pin 14, the inductance of the short-circuit pin 14 can be adjusted.

[0047] In this embodiment, the antenna device 10 includes three short-circuit pins 14A, 14B, and 14C. Short-circuit pin 14A is disposed at the center of the opposing conductor plate 13. The other two short-circuit pins 14B and 14C are located on a straight line Lx that passes through the center of the opposing conductor plate 13 and the point connecting the power supply line 15 and bisects the opposing conductor plate 13, in a direction away from the power supply line 15.

[0048] As shown in the inner view of antenna device 10 Figure 3 and as Figure 2 Sectional view along line IV-IV Figure 4 As shown, a gap 16 is formed in the base plate 11 at the location of the short-circuit pin 14. Therefore, the short-circuit pin 14 and the base plate 11 are not directly connected. Figure 3 As shown, gap 16 is rectangular in shape.

[0049] like Figure 4 As shown, short-circuit pins 14A, 14B, and 14C penetrate vertically through the support plate 12, with one end contacting the opposing conductor plate 13. In the opposing conductor plate 13, the surface on the side of the support plate 12 is designated as the conductor plate plane 17. One end of the short-circuit pins 14A, 14B, and 14C extends to this conductor plate plane 17.

[0050] The other ends of the short-circuit pins 14A, 14B, and 14C protrude from the support plate 12. The support plate 12 side of the base plate 11 is designated as the base plate plane 18. The ends of the short-circuit pins 14A, 14B, and 14C on the base plate 11 side extend beyond the base plate plane 18 and are located at the same position as the exposed surface of the base plate 11.

[0051] like Figure 4As shown, the end of the short-circuit pin 14C on the base plate 11 side is connected to the base plate 11 by conductive tape 19. Therefore, the short-circuit pin 14C conducts electricity between the base plate 11 and the opposing conductor plate 13. However, the other short-circuit pins 14A and 14B are not connected to the base plate 11, and therefore do not connect the base plate 11 to the opposing conductor plate 13.

[0052] [Operation of Antenna Device 10]

[0053] Next, the operation of the antenna device 10 configured as described will be explained. The opposing conductor plate 13 and the base plate 11 are short-circuited by the short-circuit pin 14C. The antenna device 10 achieves LC parallel resonance at a resonant frequency determined by the inductance of the short-circuit pin 14C and the electrostatic capacitance between the opposing conductor plate 13 and the base plate 11. LC parallel resonance is a resonance independent of the wavelength of the transmitted and received radio waves. This resonance is a zero-order resonance.

[0054] Through this LC parallel resonance, an electric field perpendicular to both the base plate 11 and the opposing conductor plate 13 is generated between them. This perpendicular electric field propagates from the short-circuit pin 14 toward the edge of the opposing conductor plate 13, becoming a vertically polarized wave at the edge of the opposing conductor plate 13 and propagating in space. Furthermore, a vertically polarized wave refers to an electric wave whose vibration direction is perpendicular to both the base plate 11 and the opposing conductor plate 13. When the antenna device 10 is used in an orientation parallel to the horizontal plane, the vertically polarized wave refers to a polarized wave perpendicular to the ground (i.e., a typical vertically polarized wave).

[0055] For ease of explanation, the propagation direction of the vertical electric field when the short-circuit pin 14A is connected to the base plate 11 will be explained first. For example... Figure 5 As shown, when the short-circuit pin 14A is connected to the base plate 11, the propagation direction of the vertical electric field is symmetrical about the short-circuit pin 14A. Therefore, the radiation characteristic relative to the parallel direction of the base plate is omnidirectional (in other words, all-directional). That is, the main beam of the antenna device 10 is formed in all directions from the central region of the opposing conductor plate 13 toward the edge (i.e., the parallel direction of the base plate).

[0056] Since the short-circuit pin 14A is positioned at the center of the opposing conductor plate 13, the current flowing through the opposing conductor plate 13 is symmetrical about the short-circuit pin 14A. Therefore, the electromagnetic wave emitted by the current flowing from the center of the conductor plate 13 in a certain direction in the antenna height direction is canceled out by the electromagnetic wave emitted by the current flowing in the opposite direction.

[0057] That is, when only the short-circuit pin 14A is connected to the base plate 11, the antenna device 10 does not radiate radio waves in a direction perpendicular to the base plate 11 (hereinafter, the vertical direction of the base plate). The vertical direction of the base plate... Figure 5The z-axis is equivalent to the positive z-axis direction.

[0058] exist Figure 6 The diagram shows the current flowing through the opposing conductor plate 13 when the short-circuit pin 14C is connected to the base plate 11. The short-circuit pin 14C short-circuits the opposing conductor plate 13 at a position offset from the center of the opposing conductor plate 13. Therefore, as shown... Figure 6 As shown in (A), the symmetry of the current distribution flowing through the opposing conductor plate 13 is lost.

[0059] The result is, as Figure 6 As shown in (B), the electromagnetic waves emitted by the current component in the X-axis direction are not canceled out and remain. That is, since the short-circuit pin 14C is positioned offset from the center of the opposing conductor plate 13 along the X-axis direction, linearly polarized waves (hereinafter, X-axis parallel polarized waves) with the electric field vibration direction parallel to the X-axis are emitted upward from the opposing conductor plate 13. Furthermore, since the current component in the Y-axis direction maintains symmetry, the linearly polarized waves with the electric field vibration along the Y-axis direction cancel each other out. Therefore, the Y-axis parallel polarized waves emitted from the opposing conductor plate 13 become negligible.

[0060] The connection of which short-circuit pin 14 to the base plate 11, or the placement of each short-circuit pin 14A, 14B, 14C, can be appropriately designed based on simulation. The farther the position of the short-circuit pin 14 connecting the base plate 11 to the opposing conductor plate 13 is from the center of the opposing conductor plate 13, the greater the loss of symmetry in the current distribution flowing through the opposing conductor plate 13. Therefore, the farther the position of the short-circuit pin 14 connecting the base plate 11 to the opposing conductor plate 13 is from the center of the opposing conductor plate 13, the greater the radiation gain of the linearly polarized wave in the direction perpendicular to the base plate.

[0061] Therefore, the positions of multiple short-circuit pins 14 are predetermined so that the desired radiation gain of linearly polarized waves in the direction perpendicular to the base plate can be obtained in several environments in which the antenna device 10 is configured. Then, when the antenna device 10 is actually used, a short-circuit pin 14 is selected from the multiple short-circuit pins 14 to short-circuit the base plate 11 and the opposing conductor plate 13 so that the radiation gain of linearly polarized waves in the direction perpendicular to the base plate becomes the desired radiation gain.

[0062] [Cross-sectional area of ​​short-circuit pin 14]

[0063] like Figure 2 , Figure 3 , Figure 4As shown, the further the short-circuit pin 14 is from the center of the opposing conductor plate 13, the larger the cross-sectional area of ​​the surface perpendicular to the axial direction. The reason is as follows: As described above, the antenna device 10 radiates an electric field generated by parallel resonance into space. The inductance in this parallel resonance, when the short-circuit pin 14 is located away from the center of the opposing conductor plate 13, is the resultant of the inductance of the short-circuit pin 14 and the inductance of the current flowing through the opposing conductor plate 13. The further the short-circuit pin 14 is from the center of the opposing conductor plate 13, the greater the inductance of the current flowing through the opposing conductor plate 13. Preferably, the inductance of the short-circuit pin 14 is reduced corresponding to this increase, while the resultant inductance remains constant regardless of the position of the short-circuit pin 14. Therefore, the further the short-circuit pin 14 is from the center of the opposing conductor plate 13, the larger its cross-sectional area.

[0064] [Summary of Implementation Methods]

[0065] According to the above structure, the antenna device 10 radiates a vertically polarized wave from the base plate by performing LC parallel resonance at a resonant frequency determined by the inductance of the short-circuit pin 14, etc., and the electrostatic capacitance between the opposing conductor plate 13 and the base plate 11. The thickness of the antenna device 10 is between the base plate 11 and the opposing conductor plate 13, which is much shorter than 1 / 10 of the wavelength of the radio waves transmitted and received by the antenna device 10. Therefore, the antenna device 10 can be made very low-height.

[0066] In addition, the antenna device 10 has three short-circuit pins 14A, 14B, and 14C at different distances from the center of the opposing conductor plate 13. The three short-circuit pins 14 are not directly connected to the base plate 11 and the opposing conductor plate 13, but can be selectively connected to the base plate 11 and the opposing conductor plate 13 by means of conductive tape 19.

[0067] By selecting the short-circuit pin 14 connecting the base plate 11 and the opposing conductor plate 13, the position of the short circuit between the opposing conductor plate 13 and the base plate 11 can be varied. The farther the short circuit position between the opposing conductor plate 13 and the base plate 11 is from the center of the opposing conductor plate 13, the greater the radiation gain of the linearly polarized wave in the direction perpendicular to the base plate. Therefore, by selecting the short-circuit pin 14 connecting the base plate 11 and the opposing conductor plate 13, the radiation gain of the linearly polarized wave in the direction perpendicular to the base plate can be adjusted.

[0068] Because the radiation gain of the linearly polarized wave perpendicular to the base plate can be adjusted, the polarization ratio of the two cross-polarized waves—the base plate-parallel vertically polarized wave and the linearly polarized wave perpendicular to the base plate—can be adjusted.

[0069] Furthermore, in this embodiment, for the three short-circuit pins 14, the longer the distance from the center of the opposing conductor plate 13 to the end of the short-circuit pin 14 on the opposing conductor plate 13 side, the larger the cross-sectional area of ​​the short-circuit pin 14. As a result, frequency variations emitted by the antenna device 10 due to the different short-circuit pins 14 connecting the opposing conductor plate 13 and the base plate 11 can be suppressed.

[0070] <Second Implementation>

[0071] Next, the second embodiment will be described. In this second embodiment and the following description, unless specifically mentioned, elements with the same reference numerals as those previously used are the same as those with the same reference numerals in the previous embodiments. Furthermore, even when only a portion of the structure is described, the previously described embodiments can be applied to other parts of the structure.

[0072] Figure 7 In addition to the three short-circuit pins 14A, 14B, and 14C included in the antenna device 10 of the first embodiment, the antenna device 210 shown also includes two short-circuit pins 14D and 14E. Although the side of the base plate 11 of the antenna device 210 is not shown in the figure, gaps 16 are also formed around the short-circuit pins 14D and 14E. Therefore, the short-circuit pins 14D and 14E are not directly connected to the base plate 11. The distance from the center of the opposing conductor plate 13 and the cross-sectional area of ​​each of the short-circuit pins 14D and 14E are the same as those of the short-circuit pins 14B and 14C.

[0073] In this antenna device 210, when the short-circuit pin 14D or the short-circuit pin 14E is connected to the base plate 11, a linearly polarized wave (hereinafter, Y-axis parallel polarized wave) with the electric field vibration direction parallel to the Y-axis is radiated upward from the opposing conductor plate 13. The polarization plane of the Y-axis parallel polarized wave also intersects with the polarization plane of the vertically polarized wave of the base plate.

[0074] The antenna device 210 is the same as the antenna device 10 in the first embodiment, and can adjust the polarization ratio between the vertically polarized wave in the direction parallel to the base plate and the linearly polarized wave in the direction perpendicular to the base plate. In addition, it is possible to select whether the polarization plane of the linearly polarized wave in the direction perpendicular to the base plate is parallel to the X-axis or parallel to the Y-axis.

[0075] <Third Implementation Method>

[0076] The position where the short-circuit pin 14 connects to the opposing conductor plate 13 is not limited to the straight lines Lx and Ly that bisect the opposing conductor plate 13. Figure 8In the antenna device 310 shown, in addition to the short-circuit pin 14A provided in the antenna device 10 of the first embodiment, two short-circuit pins 14F and 14G are also provided. These two short-circuit pins 14F and 14G are connected to the opposing conductor plate 13 on a straight line at a distance equal to that of the straight line Lx and the straight line Ly.

[0077] <Fourth Implementation>

[0078] In the first embodiment, the short-circuiting pin 14 is selectively connected to the base plate 11 by conductive tape 19. However, the component connecting the short-circuiting pin 14 to the base plate 11 is not limited to conductive tape 19. Figure 9 In the antenna device 410 shown, switch 20 connects the end of each short-circuit pin 14 on the base plate 11 side to the base plate 11. In this way, by selecting the on switch 20, the short-circuit pin 14 connecting the base plate 11 to the opposing conductor plate 13 can be selected.

[0079] In addition to conductive tape 19 and switch 20, short-circuit pin 14 can also be connected to base plate 11 by various methods (e.g., solder).

[0080] The implementation methods have been described above, but the disclosed technology is not limited to the above-described implementation methods. The following variations are also included in the scope of the disclosure, and various changes and implementations can be made without departing from the spirit of the text, except as described below.

[0081] <Variation Example 1>

[0082] In the previously described embodiment, a plurality of short-circuit pins 14 are provided at different distances from the center of the opposing conductor plate 13. However, it is also possible to provide only a plurality of short-circuit pins 14 that are at the same distance from the center of the opposing conductor plate 13, although the directions from the center of the opposing conductor plate 13 toward the ends of the short-circuit pins 14 on the opposing conductor plate 13 side are different.

[0083] For example, in Figure 7 The antenna device 210 may also include only short-circuit pins 14C and 14E, or only short-circuit pins 14B and 14D. In this case, there are two short-circuit pins 14. The number of short-circuit pins 14 can be multiple, not limited to two or three, and may also be four or more.

[0084] For example, with only short-circuit pins 14C and 14E available, the direction of the polarization plane of the linearly polarized wave in the vertical direction of the base plate can be adjusted by choosing which short-circuit pin 14 connects the base plate 11 to the opposing conductor plate 13. The direction of the polarization plane is also one of the polarization characteristics.

[0085] <Variation Example 2>

[0086] In this embodiment, there is one slot 16, which is rectangular in shape. However, the slot can also be divided into multiple slots, and the shape of the slots is not limited to rectangles. For example, slot 16 can also be provided for each short-circuit pin 14. Alternatively, the shape of the slot can also be circular.

[0087] <Variation Example 3>

[0088] It is not necessary to configure the base plate 11 and the opposing conductor plate 13 such that the centers of the opposing conductor plate 13 and the base plate 11 overlap when viewed from above.

[0089] <Variation Example 4>

[0090] In one embodiment, the end of each short-circuit pin 14 on the base plate 11 side is not directly connected to the base plate 11, but the end on the opposing conductor plate 13 side is connected to the opposing conductor plate 13. However, it is also possible to do the opposite, with the end of each short-circuit pin 14 on the base plate 11 side connected to the base plate 11, while selectively connecting the end on the opposing conductor plate 13 side to the opposing conductor plate 13.

[0091] <Variation Example 5>

[0092] In this embodiment, any one of the short-circuit pins 14 is connected to the base plate 11. However, two or more short-circuit pins 14 may also be connected to the base plate 11 simultaneously.

[0093] <Variation Example 6>

[0094] The short-circuit pin 14 can also be connected to the opposing conductor plate 13 at a position closer to the power supply line 15 than the center of the opposing conductor plate 13.

Claims

1. An antenna device, wherein, have: The base plate is a flat conductor component; The opposing conductor plate is a flat conductor component that is set at a predetermined interval from the aforementioned base plate and is electrically connected to the power supply line; as well as Multiple short-circuit pins are used to electrically connect the aforementioned opposing conductor plate to the aforementioned base plate. One end of each of the aforementioned short-circuit pins extends to the plane of the conductor plate, and the other end extends to the plane of the base plate. The plane of the conductor plate is a plane that includes the opposing conductor plate, and the plane of the base plate is a plane that includes the base plate. One or more of the aforementioned short-circuit pins can be selected to connect the aforementioned opposing conductor plate to the aforementioned base plate. For each of the aforementioned short-circuit pins, the distance from the center of the opposing conductor plate to the end of the short-circuit pin on the opposing conductor plate side is different from one another. The longer the distance from the center of the aforementioned opposing conductor plate to the end of the aforementioned short-circuit pin on the opposing conductor plate side, the larger the cross-sectional area of ​​the aforementioned short-circuit pin.

2. The antenna device according to claim 1, wherein, For the multiple short-circuit pins mentioned above, the directions from the center of the opposing conductor plate toward the end of the short-circuit pin on the opposing conductor plate side are different from each other.

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