JP6899942B2 - Planar antenna and antenna device - Google Patents

Description

The present invention relates to a planar antenna and an antenna device.

Patent Document 1 discloses a planar antenna in which conductor layers are arranged on both sides of a dielectric layer. In this planar antenna, a material in which a polyolefin resin and a glass fiber are laminated is used as the dielectric material, instead of the foamed polyethylene used as the material of the conventional dielectric material. As a result, the planar antenna of Patent Document 1 can obtain high antenna characteristics.

Japanese Unexamined Patent Publication No. 2013-89995

However, in the planar antenna of Patent Document 1, although high antenna characteristics are obtained by changing the material and composition of the dielectric from the conventional materials, the presence of the dielectric has a considerable influence on the antenna characteristics. That is, in the antenna of Patent Document 1, electromagnetic waves are transmitted and received by traveling through the dielectric while reflecting electromagnetic waves between both conductors sandwiching the dielectric. Therefore, there is a problem that the intensity of the electromagnetic wave is lost due to the presence of the dielectric, and as a result, the transmission / reception characteristics of the antenna are lost. Therefore, there has been a demand for a configuration capable of further suppressing antenna loss.

Therefore, an object of the present invention is to provide a planar antenna and an antenna device capable of suppressing antenna loss.

A planar antenna according to one aspect of the present invention includes at least one antenna conductor, an opposing conductor, and at least one support. The antenna conductor transmits and receives electromagnetic waves and constitutes a reflection wall of the electromagnetic waves. The opposing conductor faces the antenna conductor and constitutes a reflecting wall for the electromagnetic wave. The support portion forms a gap between the at least one antenna conductor and the opposing conductor.

According to the above configuration, since the antenna conductor and the opposing conductor, which are mutually electromagnetic wave reflecting walls, are supported by the support portion so as to have a gap between them, the ratio between the antenna conductor and the opposing conductor is Intervening is air having a dielectric constant of about 1.0. Since the relative permittivity of air is smaller than that in the case where a dielectric material is interposed between the antenna conductor and the opposing conductor, it is possible to suppress the power loss of the electromagnetic wave propagating between the antenna conductor and the opposing conductor.

Further, since the support portion only needs to support the antenna conductor with respect to the opposing conductor, air can be interposed between the antenna conductor and the opposing conductor with a simple configuration. Further, since it is not necessary to support the antenna conductor with a separate substrate, it is possible to realize miniaturization, weight reduction, and cost reduction of the flat antenna.

In the plane antenna, at least one support portion is provided on a straight line extending in a direction orthogonal to the resonance direction of the electromagnetic wave, passing near the center of the antenna conductor in the plan view of the plane antenna. be able to.

The electromagnetic wave whose reflection wall is the antenna conductor is in a resonance state, and a standing wave is generated. At this time, a standing wave node is located at the center of the antenna element in the resonance direction. Then, a straight line passing near the center of the antenna conductor and orthogonal to the resonance direction extends corresponding to the position of the node of the standing wave. Therefore, on the straight line passing near the center, the electric field strength of the electromagnetic wave is smaller than that of other regions other than the vicinity of the center. Therefore, by connecting the support portion and the antenna conductor on this straight line, it is possible to suppress the influence on the electromagnetic wave propagating between the antenna conductor and the opposite conductor, which is caused by providing the support portion, and suppress the antenna loss. ..

The term "near the center" may be any region of the antenna conductor where the electric field strength is small, and includes not only the central portion of the antenna conductor but also the central portion and its vicinity. Further, "orthogonal" includes generally orthogonal, and includes, for example, a case where the resonance direction and the straight line intersect at an angle of about 80 ° to about 100 °. Further, as for the support portion, at least the connection portion with the antenna conductor needs to be located on a straight line, and the entire support portion does not necessarily have to be located on a straight line.

In the plane antenna, in the plan view of the plane antenna, the at least one support portion may be arranged in a region of the vicinity of the center of the antenna conductor excluding the side of the outer peripheral edge of the antenna conductor. ..

The electric field strength of the electromagnetic wave in the vicinity of the center of the antenna conductor is smaller than that in the region other than the vicinity of the center. However, the strength of electromagnetic waves tends to be stronger at the sides of the antenna conductor than at the center. It is considered that this is because the effective permittivity of the antenna conductor changes when the antenna conductor comes into contact with air on the side of the antenna conductor, and this change makes it easier for electromagnetic waves to concentrate. In the above configuration, the support portion is arranged in a region excluding the side of the antenna conductor where the intensity of the electromagnetic wave is small, unlike the side of the antenna conductor. As a result, the influence of the antenna conductor on the electromagnetic wave caused by the provision of the support portion can be suppressed, and the antenna loss can be suppressed.

In the planar antenna, in plan view, the antenna conductor may include a set of first sides extending along the resonance direction and facing each other. At this time, the support portion is provided near the center of each of the first side of the set and extends toward the opposing conductor.

As described above, the vicinity of the center of the antenna conductor in the resonance direction corresponds to the position of the node of the standing wave, and the electric field strength of the electromagnetic wave is smaller than that of other regions other than the vicinity of the center. In the above configuration, in the vicinity of the center of the antenna conductor in the resonance direction, each support portion extends from each of the first side of the set toward the opposite conductor. Therefore, it is possible to suppress the influence of the antenna conductor on the electromagnetic wave caused by providing the support portion and suppress the antenna loss.

In the planar antenna, in plan view, the antenna conductor may include a set of first sides extending along the resonance direction and facing each other. At this time, the support portion is connected to each of the first side of the set. Then, each of the support portions has a horizontal portion extending from the vicinity of the center of the first side toward the end distant from the antenna conductor along the plane direction of the antenna conductor, and the horizontal portion extending from the end of the horizontal portion. Includes a vertical portion extending towards the opposing conductor.

As described above, the vicinity of the center of the antenna conductor in the resonance direction corresponds to the position of the node of the standing wave, and the electric field strength of the electromagnetic wave is smaller than that of other regions other than the vicinity of the center. However, on the first side of the antenna conductor, the intensity of the electromagnetic wave tends to be higher than that in the central portion of the antenna conductor. It is considered that this is because, on the first side, the effective dielectric constant of the antenna conductor changes when the antenna conductor comes into contact with air, and this change makes it easier for electromagnetic waves to concentrate.

In the above configuration, first, the horizontal portion of the support portion extends along a plane toward the end point away from the antenna conductor, starting from the first side near the center in the resonance direction of the antenna conductor. That is, in the support portion, the horizontal portion first extends along the plane of the antenna conductor so as to be separated from the first side of the antenna conductor having a high intensity of electromagnetic waves. As a result, it is possible to suppress the concentration of electromagnetic waves having a large electric field strength in the horizontal portion. Then, the vertical portion of the support portion extends from the end of the horizontal portion of the support portion toward the opposing conductor. As a result, the influence of the antenna conductor on the electromagnetic wave caused by the provision of the support portion can be suppressed, and the antenna loss can be suppressed.

In the planar antenna, in a planar view, each of the first side of the set and the connecting portion of each support portion are symmetrical with respect to a straight line passing through the center of the antenna conductor and along the resonance direction of the electromagnetic wave. be able to.

In the above configuration, the connecting portion between the antenna conductor and each support portion is located symmetrically with respect to a straight line along the resonance direction. Therefore, the influences of the supporting portions facing each other on the electromagnetic waves in the antenna conductor are symmetrical. As a result, the resonance state of the electromagnetic wave in the antenna conductor can be maintained symmetrically with respect to the vicinity of the center. Therefore, the antenna loss due to the non-uniform resonance state can be suppressed.

In the flat antenna, the connection portion between the at least one support portion and the antenna conductor may be located in a region of the antenna conductor where the electric field strength is small.

In the above configuration, the support portion is connected to the region of the antenna conductor where the electric field strength is small. Therefore, it is possible to suppress the influence of the antenna conductor on the electromagnetic wave caused by providing the support portion and suppress the antenna loss.

In the plane antenna, the antenna conductor may include at least a set of second sides parallel to each other orthogonal to the resonance direction of the electromagnetic wave in a plane view.

In the above configuration, the electromagnetic wave is in a resonance state and a standing wave is formed with a pair of parallel second sides of the antenna conductor as the edge. The antinode of the standing wave is located at the edge of the second side of the set, and the node of the standing wave is located at the center of the second side of the set. At this time, the electromagnetic wave in the antenna conductor resonates at a certain resonance frequency, and the power loss can be minimized.

In the plane antenna, if the in-tube wavelength of the electromagnetic wave in the antenna conductor is λg, the distance between the second sides of the set can be λg / 2.

According to the above configuration, a standing wave is generated with the second side of the set as the antinode and the center of the second side of the set as the node. At this time, the electromagnetic wave in the antenna conductor resonates at a certain resonance frequency, and the power loss can be minimized.

In the plane antenna, the at least one support portion can be connected in the vicinity of the center of the antenna conductor and in the vicinity of λg / 4 from the second side of the set.

The neighborhood of λg / 4 from the second side of the set is the central portion between the second sides of the set. In the vicinity of λg / 4 from the second side of this set, the node of the standing wave is located, and the electric field strength of the electromagnetic wave is smaller than that of the other regions. By providing the support portion at this position, the influence of the support portion on the electromagnetic wave in the antenna conductor can be suppressed, and the antenna loss can be suppressed.
The neighborhood of λg / 4 from the second side of the set may be, for example, within the range of ± λg / 8 centered on λg / 4 from the second side of the set.

In the plane antenna, the plane shape of the antenna conductor can be rectangular.

The antenna conductor has a rectangular shape such as a rectangle, a square, and a trapezoid. With such a rectangular shape, for example, a standing wave having sides parallel to each other as end edges is formed, and the electromagnetic wave is in a resonance state. As a result, antenna loss can be suppressed.

In the above-mentioned planar antenna, a plurality of antenna conductors are provided, and a connecting conductor for connecting adjacent antenna conductors can be further provided.

By connecting and arranging a plurality of antenna conductors with connecting conductors, the sensitivity of transmitting and receiving electromagnetic waves can be improved.

The antenna device according to one aspect of the present invention includes the planar antenna according to any one of the above, and a power converter that converts the power of electromagnetic waves transmitted and received by the planar antenna.

The antenna device may further include a high frequency circuit connected to the power converter.

According to the present invention, it is possible to provide a planar antenna and an antenna device capable of suppressing antenna loss.

The perspective view of the antenna apparatus including the plane antenna which concerns on 1st Embodiment. An enlarged view of a region of the planar antenna of FIG. 1 including the first antenna conductor and the second antenna conductor. FIG. 2 is a cross-sectional view taken along the line AA of FIG. An analysis diagram showing an electric field strength distribution when a plane antenna is viewed in a plane. FIG. 5 is a perspective view showing configuration 1 in which the planar antenna 100 is connected to the power converter 200. FIG. 5 is a cross-sectional view taken along the straight line α of FIG. An exploded perspective view showing configuration 2 in which the planar antenna 100 is connected to the power converter 200. The perspective view which shows the structure which the coaxial cable is connected to a plane antenna. FIG. 5 is a plan view showing the arrangement relationship of the left support portion 15L and the right support portion 15R with respect to the antenna conductor 13. FIG. 5 is a plan view showing the arrangement relationship of the left support portion 15L and the right support portion 15R with respect to the antenna conductor 13. The perspective view of the antenna apparatus including the plane antenna which concerns on 2nd Embodiment. 11 is an enlarged view of a region of the planar antenna of FIG. 11 including the first antenna conductor and the second antenna conductor. FIG. 12 is a cross-sectional view taken along the line AA of FIG. An analysis diagram showing an electric field strength distribution when a plane antenna is viewed in a plane. FIG. 3 is a perspective view of an antenna device including a planar antenna according to a third embodiment. FIG. 5 is an enlarged view of a region of the planar antenna of FIG. 15 including the first antenna conductor and the second antenna conductor. FIG. 16 is a cross-sectional view taken along the line AA of FIG. An analysis diagram showing an electric field strength distribution when a plane antenna is viewed in a plane. FIG. 3 is a perspective view of an antenna device when the support portion of the first embodiment is provided on a connecting conductor. FIG. 3 is a perspective view of an antenna device when the support portion of the second embodiment is provided on the connecting conductor. FIG. 3 is a perspective view of an antenna device when the support portion of the third embodiment is provided on the connecting conductor. Top view showing another shape of the antenna conductor. Top view showing another shape of the antenna conductor. Explanatory drawing when a plurality of antenna conductors are arranged in a plurality of rows. Explanatory drawing when a plurality of antenna conductors are arranged in a plurality of rows. Explanatory drawing when a plurality of antenna conductors are arranged in a plurality of rows. A perspective view of an antenna device including an ideal planar antenna. An enlarged view of a region including the first antenna conductor and the second antenna conductor in the ideal plane antenna of FIG. 25. FIG. 25 is a cross-sectional view taken along the line AA of FIG. Electric field strength distribution of the ideal plane antenna 195. Directivity of the planar antenna of Example 1-1. Directivity of the planar antenna of Example 1-2. Directivity of the planar antenna of Examples 1-3. Directivity of an ideal planar antenna. FIG. 3 is a perspective view of an antenna device including the planar antenna of Comparative Example 1. FIG. 33 is a cross-sectional view taken along the line AA. Electric field strength distribution in the planar antenna 5000 of Comparative Example 1. Directivity of the planar antenna 5000 of Comparative Example 1 The explanatory view which shows the electric field strength distribution of the plane antenna 1001 of Example 2-1. The explanatory view which shows the electric field strength distribution of the plane antenna 1002 of Example 2-2.

Hereinafter, the planar antenna according to the first embodiment of the present invention and the antenna device including the planar antenna will be described with reference to the drawings.

<1. First Embodiment>
(1) Schematic Configuration of Antenna Device FIG. 1 is a perspective view of an antenna device including a planar antenna according to the first embodiment. FIG. 2 is an enlarged view of a region of the planar antenna of FIG. 1 including the first antenna conductor and the second antenna conductor. FIG. 3 is a cross-sectional view taken along the line AA of FIG.

As shown in FIG. 1, the antenna device 1000 according to the present embodiment includes a planar antenna 100 that receives and transmits electromagnetic waves, a high-frequency circuit 300 that transmits and receives high frequencies such as millimeter waves and microwaves, and a planar antenna 100 and a high-frequency circuit 300. Includes a power converter 200 that converts power between and. The high frequency circuit 300 is, for example, an MMIC (monolithic microwave integrated circuit), which transmits and receives high frequencies such as millimeter waves and microwaves as described above. Then, the planar antenna 100 is transmitted from the high frequency circuit 300 and emits an electromagnetic wave whose power is converted by the power converter 200. On the other hand, when the planar antenna 100 receives an electromagnetic wave, the received electromagnetic wave is transmitted to the high frequency circuit 300 via the power converter 200. Hereinafter, each member will be described in detail.

(2) Overall Configuration of Planar Antenna First, the overall configuration of the planar antenna 100 according to the first embodiment will be described. In the following, explanations will be given in the directions shown in FIG. 1, that is, up, down, front, back, right, and left. However, the present invention is not limited by this direction, but the "front-back direction" of the present embodiment corresponds to the resonance direction of the present invention, and the "left-right direction" corresponds to the direction orthogonal to the resonance direction of the present invention. Equivalent to.

Further, in the following description, the wavelength in the tube of a certain part means the wavelength of the electromagnetic wave of a certain part influenced by all the configurations adjacent to the certain part. For example, as will be described later, the in-tube wavelength of the electromagnetic wave in the antenna conductor 13 means the wavelength of the electromagnetic wave in the antenna conductor 13 influenced by all the configurations around the antenna conductor 13, such as air adjacent to the antenna conductor 13. It shall be.

As shown in FIG. 1, the flat antenna 100 uses four antenna conductors 13 (13a to 13d) for transmitting and receiving electromagnetic waves, a grounded ground conductor (opposing conductor) 16, and each antenna conductor 13 as a ground conductor 16. It includes a support portion 15 that supports the support. Further, the four antenna conductors 13a to 13d are arranged in a straight line and are connected to each other by the connecting conductors 11b to 11d. Then, the antenna conductor 13a arranged at the end is connected to the power converter 200 via the connecting conductor 11a. The antenna conductor 13 and the ground conductor 16 are formed of flat conductors, and are arranged so as to face each other in the vertical direction. Therefore, the electromagnetic wave propagates between the antenna conductor 13 and the ground conductor 16 while being reflected. In the following, for convenience of explanation, the antenna conductors arranged from the rear to the front are referred to as a first antenna conductor 13a, a second antenna conductor 13b, a third antenna conductor 13c, and a fourth antenna conductor 14d, respectively. I will do it. Further, the connecting conductors 11 arranged from the rear to the front are referred to as a first connecting conductor 11a, a second connecting conductor 11b, a third connecting conductor 11c, and a fourth connecting conductor 11d, respectively. By alternately connecting the plurality of antenna conductors 13 and the connecting conductors 11 in a row in this way, the transmission / reception sensitivity of electromagnetic waves can be improved.

Further, each antenna conductor 13 is supported by the above-mentioned support portions 15 (15a to 15d) so as to have a gap between the antenna conductor 13 and the ground conductor 16. For example, the first antenna conductor 13a is supported with respect to the ground conductor 16 by the left first support portion 15La connected to the left side and the right first support portion 15Ra connected to the right side. The left first support portion 15La and the right first support portion 15Ra are integrally formed with the first antenna conductor 13a, and the left and right sides of the first antenna conductor 13a are substantially uniform and stable with respect to the ground conductor 16. I support it.

Similarly, the second antenna conductor 13b is supported by a second support portion 15b having a left second support portion 15Lb and a right second support portion 15Rb. The other third antenna conductor 13c is also supported by the third support portion 15c (15Lc, 15Rc), and the fourth antenna conductor 13d is also supported by the fourth support portion 15d (15Ld, 15Rd).

(3) Configuration of Each Part of the Planar Antenna Next, the antenna conductor 13, the connecting conductor 11, the support portion 15, and the ground conductor 16, which are the respective parts of the flat antenna 100, will be further described. The first to fourth antenna conductors 13a to 13d, the connecting conductors 11a to 11d, and the support portions 15a to 15d have substantially the same configuration. Therefore, the first antenna conductor 13a, the first connecting conductor 11a, the second connecting conductor 11b, and the first support portion 15a will be described, and the other second to fourth antenna conductors 13b to 13d and the third to fourth connecting conductors 11c will be described. The description of ~ 11d and the second to fourth support portions 15b to 15d will be omitted.

(3-1) First antenna conductor 13a
As shown in FIG. 2, the first antenna conductor 13a is a rectangular plate having four sides, that is, a set of first side 19a extending in the front-rear direction and a set of second sides 17a extending in the left-right direction. It is formed by the shape. A set of first side 19a has a left first side 19La and a right first side 19Ra facing each other in the left-right direction and parallel to each other. A set of second sides 17a has a front second side 17F and a rear second side 17Ba that face each other in the front-rear direction and are parallel to each other.

The length L1 of the distance between the front second side 17F and the rear second side 17Ba can be 1 / 2λg, where λg is the in-tube wavelength of the electromagnetic wave in the first antenna conductor 13a. In other words, the length L1 of the left first side 19La and the right first side 19Ra in the front-rear direction can be 1 / 2λg. The length L1 can be, for example, 1.5 mm to 1.9 mm. When the length L1 is 1 / 2λg, the electromagnetic wave in the first antenna conductor 13a is in a resonance state with the front-rear direction as the resonance direction, and a standing wave is generated. Specifically, the electromagnetic wave that travels from the back to the front of the first connecting conductor 11a and enters the first antenna conductor 13a becomes a standing wave that repeatedly reflects in the front-rear direction of the first antenna conductor 13a. At this time, the antinodes of the standing waves are located on the front second side 17F and the rear second side 17Ba facing each other in the front-rear direction. On the other hand, if a straight line γ that passes through the center point β that is the center of the first antenna conductor 13a in the front-rear direction and the left-right direction and extends in the left-right direction is defined, a node of the standing wave is located on this straight line γ. In this way, the electromagnetic wave in the antenna conductor 13 resonates at a certain resonance frequency to form a standing wave, so that the power loss can be minimized. The straight line γ is orthogonal to the straight line α that passes through the center point β and extends along the resonance direction. Here, "orthogonal" includes generally orthogonal, and includes, for example, the case where the straight line α and the straight line γ intersect at an angle of about 80 ° to about 100 °.

The length L2 of the distance between the left first side 19La and the right first side 19Ra is not particularly limited as long as it is longer than the lateral length L3 of the first connecting conductor 11a and the second connecting conductor 11b, which will be described later. The length L2 can be, for example, longer than the length L3 and shorter than the length L1, and can be, for example, 1 mm.

The first antenna conductor 13a has a substantially uniform thickness W2. The thickness W2 is not particularly limited. However, the smaller the W2, the thinner the first antenna conductor 13a can be formed, and the thinner the flat antenna 100 can be. The thickness W2 can be, for example, 0.012 mm to 0.300 mm.

(3-2) First connecting conductor 11a and second connecting conductor 11b
The first connecting conductor 11a is a rectangular parallelepiped rod-shaped member extending in the front-rear direction. The first connecting conductor 11a connects the power converter 200 and the planar antenna 100. Therefore, the first connecting conductor 11a outputs the electromagnetic wave output from the power converter 200 to the planar antenna 100. Further, on the contrary, the first connecting conductor 11a outputs the electromagnetic wave output from the planar antenna 100 to the power converter 200.

The first connecting conductor 11a is connected so as to project rearward from the center of the rear second side 17Ba of the first antenna conductor 13a. Specifically, the first connecting conductor 11a passes through the center point β of the first antenna conductor 13a and extends along a straight line α extending in the front-rear direction.

The length L3 of the first connecting conductor 11a in the left-right direction is determined by the magnitude of impedance required for the first connecting conductor 11a and the like. For example, the length L3 is a distance at which the impedance becomes about 100Ω, and can be 0.2 mm to 0.25 mm. However, the left-right length L3 of the first connecting conductor 11a is smaller than the left-right length L2 of the front second side 17F and the rear second side 17Ba. In particular, the length L3 is preferably sufficiently smaller than the length L2. As a result, while propagating the electromagnetic wave between the first connecting conductor 11a and the first antenna conductor 13a, the electromagnetic wave can be reflected with the front second side 17F and the rear second side 17Ba of the first antenna conductor 13a as end faces. it can. Therefore, a standing wave can be generated in the first antenna conductor 13a by setting the electromagnetic wave in a resonance state with the front-rear direction as the resonance direction. On the other hand, when the length L3 is the length L2 or more, there is no wall surface for reflecting the electromagnetic wave in the front-rear direction in the first antenna conductor 13a. Therefore, it is not possible to generate a standing wave in the first antenna conductor 13a with the electromagnetic wave as a resonance state.

Further, the vertical thickness W3 of the first connecting conductor 11a is substantially the same as the thickness W2 of the first antenna conductor 13a. For example, the thickness W3 may be determined by the magnitude of impedance required for the first connecting conductor 11a.

The length L4 of the first connecting conductor 11a in the front-rear direction is determined by the distance between the first antenna conductor 13a and the power converter 200 and the like. However, the length L4 may be the same as the length L5 in the front-rear direction of the second connecting conductor 11b described later.

The second connecting conductor 11b is a rectangular parallelepiped rod-shaped member extending in the front-rear direction like the first connecting conductor 11a. The second connecting conductor 11b connects the adjacent first antenna conductor 13a and the second antenna conductor 13b, and propagates an electromagnetic wave between the first antenna conductor 13a and the second antenna conductor 13b. The second connecting conductor 11b is connected to the center of the first antenna conductor 13a and the second antenna conductor 13b in the left-right direction, and extends along a straight line α like the first connecting conductor 11a. The dimensions of the second connecting conductor 11b are almost the same as those of the first connecting conductor 11a.

(3-3) First support portion 15a
The left first support portion 15La and the right first support portion 15Ra constituting the first support portion 15a support the antenna conductor 13a so that the first antenna conductor 13a has a gap between the first antenna conductor 13a and the ground conductor 16. Since the left first support portion 15La and the right first support portion 15Ra are symmetrical with respect to the straight line α, only the right first support portion 15Ra will be described.

The right first support portion 15Ra is formed in an L shape having a right first horizontal portion 15HRa and a right first vertical portion 15VRa. The right first horizontal portion 15HRa is a rectangular parallelepiped rod-shaped member extending in the left-right direction, is connected to the center of the right first side 19Ra of the first antenna conductor 13a, and extends along a straight line γ. Then, the right first vertical portion 15VRa is connected to the right end portion of the right first horizontal portion 15HRa. The right first vertical portion 15VRa extends in the vertical direction, and its lower end is connected to the ground conductor 16. For example, the lower end of the right first vertical portion 15VRa can be inserted and fixed in the opening provided in the ground conductor 16.

Here, the reason why the right first horizontal portion 15HRa is connected along the straight line γ will be described below. FIG. 4 is an analysis diagram showing the electric field strength distribution when the plane antenna is viewed in a plane. In FIG. 4, for example, an electromagnetic wave having a power of 1 W and 76 GHz is supplied from the first connecting conductor 11a. Referring to the enlarged electric field strength distribution of the first antenna conductor 13a, the electric field strength is the largest in the regions I, II, III and IV including the four corners of the first antenna conductor 13a. On the other hand, the electric field strength was the smallest in the region V including the straight line γ. That is, the electric field strength of the region V is smaller than that of the regions I, II, III and IV. This is because the antinodes of the standing wave of the electromagnetic wave in the first antenna conductor 13a are located on the front second side 17F and the rear second side 17Ba, and the node of the standing wave includes the straight line γ in the center of the first antenna conductor 13a. This is because it is located in the vicinity (region V). In the region where the node of this standing wave is located, the potential becomes zero and a short circuit occurs. Then, as described above, the first antenna conductor 13a and the ground conductor are generated by providing the right first support portion 15Ra by connecting the right first horizontal portion 15HRa and the first antenna conductor 13a on the straight line γ. The influence on the electromagnetic wave propagating between 16 and 16 can be suppressed, and the antenna loss can be suppressed.

The length L6 of the right first horizontal portion 15HRa in the front-rear direction is not particularly limited. However, the smaller the length L6, the smaller the influence of the right first support portion 15Ra on the electromagnetic waves in the first antenna conductor 13a, which is preferable. For example, the length L6 is preferably sufficiently smaller than the length L1 in the front-rear direction of the right first side 19Ra, and can be, for example, 0.100 mm to 0.400 mm.

The vertical thickness W4 of the right first horizontal portion 15HRa can be substantially the same as the thickness W2 of the first antenna conductor 13a and the thickness W3 of the first connecting conductor 11a. However, the thickness W4 and the thickness W3 and the thickness W2 may be different.

Here, the length L9 is the distance from the straight line α to the right end of the right first horizontal portion 15HRa, and the length L8 in the left-right direction of the right first horizontal portion 15HRa is from the length L9 to the length L2 / 2. It is the subtracted length (L8 = L9-L2 / 2). This length L9 is approximately (1/4) λg × k (k is an integer of 1 or more). The length L9 can be, for example, 0.600 mm to 2 mm. Therefore, the length L10 in the left-right direction from the left end of the left first horizontal portion 15HRa to the right end of the right first horizontal portion 15HRa is 2 × L9 (L10 = 2 × L9).

The length of the right first vertical portion 15VRa in the front-rear direction is substantially the same as the length L6 of the right first horizontal portion 15HRa in the front-rear direction. Further, the vertical length L7 of the right first vertical portion 15VRa is larger than the thickness W2 of the first antenna conductor 13a so that a gap can be formed between the first antenna conductor 13a and the ground conductor 16, and is right. It is larger than the vertical thickness W4 of the first horizontal portion 15HRa. Further, the length L7 is preferably a length capable of confining electromagnetic waves between the first antenna conductor 13a and the ground conductor 16. Specifically, the length L7 can be, for example, 0.080 mm to 0.250 mm. On the other hand, the length L11 of the right first vertical portion 15VRa in the left-right direction shown in FIG. 3 is determined based on, for example, the strength capable of supporting the first antenna conductor 13a and the right first horizontal portion 15HRa. Specifically, the length L11 can be, for example, 0.020 mm to 0.200 mm.

(3-4) Ground conductor 16
The ground conductor 16 faces each of the antenna conductors 13a to 13d, the connection conductors 11a to 11d, and the support portions 15a to 15d, and is formed of a single flat conductor having a larger overlapping area with these. There is. The vertical thickness W1 of the ground conductor 16 can be, for example, 0.012 mm to 1 mm.

(3-5) Material and Processing Method of Flat Antenna 100 The above-mentioned antenna conductor 13, ground conductor 16, connecting conductor 11 and support portion 15 are formed of conductors, for example, gold, silver, copper, copper alloy, aluminum and the like. The appropriate material is selected from the metals of. The antenna conductor 13, the connecting conductor 11, and the support portion 15 can be integrally formed by, for example, punching. In addition, the antenna conductor 13, the connecting conductor 11, and the support portion 15 are obtained by forming a thin-film integrally on the substrate by plating treatment, photoresist lithography, or the like, and then peeling the formed conductor from the substrate. You may. The ground conductor 16 may be formed in the same manner.

Further, the antenna conductor 13, the connecting conductor 11, the support portion 15, and the ground conductor 16 may be made of different materials. Further, the support portion 15 may not be a conductor but may be, for example, an insulating material. When the support portion 15 is formed of an insulating material, even if the support portion 15 is provided on the antenna conductor 13, the electromagnetic wave in the antenna conductor 13 is caused by the support portion 15 due to the difference in conductivity between the antenna conductor 13 and the support portion 15. It can be suppressed from being affected.

(4) Power Converter Next, the configuration of the power converter 200 to which the above-mentioned planar antenna 100 is connected will be described. In the following, configurations 1 and 2 will be described as examples of the power converter. That is, one of the configurations 1 and 2 can be used as the power converter, but a power converter having any other configuration can be used. However, the power converter 200 is not limited to these configurations as long as the power can be converted between the planar antenna 100 and the high frequency circuit 300. In the following, the high frequency circuit 300 connected to the power converter 200 is omitted. The high frequency circuit 300 is electrically connected to the power converter 200, for example, by being mounted on the power converter 200 or being connected to the power converter 200 via wiring or the like.

(4-1) Configuration 1
First, configuration 1 of the power converter 200 will be described. FIG. 5 is a perspective view showing the configuration 1 in which the planar antenna 100 is connected to the power converter 200. FIG. 6 is a cross-sectional view taken along the straight line α of FIG. In FIGS. 5 and 6, the planar antenna 100 has the same configuration as that of the first embodiment, and thus the description thereof will be omitted.

As shown in FIGS. 5 and 6, the power converter 200 includes a plate-shaped first substrate unit 101, a plate-shaped second substrate unit 102 arranged to face the upper side of the first substrate unit 101, and these. It includes a dielectric substrate 130 sandwiched between the substrate units 101 and 102.

The first substrate unit 101 includes a rectangular first substrate 110, and has a rectangular coupling element 111, a first transmission pattern 112, and a ground potential on the first upper surface 110a of the first substrate 110. The upper surface ground 113 is arranged. The first transmission pattern 112 extends in the front-rear direction, and a high-frequency circuit 300 (not shown) can be connected to the first end portion 112a on the rear side. Further, the first transmission pattern 112 is connected to the coupling element 111 at the second end portion 112b on the front side. On the other hand, on the first lower surface 110b of the first substrate 110, a first lower surface ground 114 having a ground potential over the entire surface is arranged. Further, a plurality of through holes 116 penetrating the first substrate 110 are formed on the first substrate 110. The plurality of through holes 116 are arranged so as to surround the coupling element 111 and the first transmission pattern 112.

The second substrate unit 102 includes a second substrate 120, and a rectangular shield plate 127 and a second transmission pattern 128 are arranged on the second upper surface 120a of the second substrate 120. A notch 127a is formed in the front end portion of the shield plate 127, and the first end portion 128a of the second transmission pattern 128 is inserted. The second transmission pattern 128 extends forward, and the second end 128b is connected to the first connecting conductor 11a of the planar antenna 100. On the other hand, on the second lower surface 120b of the second substrate 120, a matching element 121 and a second transmission ground 123 having a ground potential and facing the second transmission pattern 128 are arranged. The matching element 121 and the coupling element 111 face each other via the dielectric substrate 130. Further, a part of the first end portion 128a of the second transmission pattern 128 faces the matching element 121.

In the power converter 200 described above, electromagnetic waves are input from the high frequency circuit 300 to the first end 112a of the first transmission pattern 112. The input electromagnetic wave is transmitted to the second end portion 112b of the first transmission pattern 112, and is supplied to the coupling element 111 which is continuous with the second end portion 112b. Next, the coupling element 111 and the matching element 121 are electromagnetically coupled to each other via the dielectric substrate 130, and power conversion is performed between the coupling element 111 and the matching element 121. The electromagnetic wave that has passed through the matching element 121 is transmitted from the first end 128a of the second transmission pattern 128 toward the second end 128b and is supplied to the first connecting conductor 11a of the planar antenna 100. The second transmission pattern 128 and the first connecting conductor 11a may be integrally formed conductors. When an electromagnetic wave is supplied to the first connecting conductor 11a, the electromagnetic wave is radiated from the antenna conductor 13 of the planar antenna 100. On the other hand, when the planar antenna 100 receives the electromagnetic wave from the antenna conductor 13, the electromagnetic wave is transmitted to the high frequency circuit 300 via the power converter 200 in the reverse order of the above.

(4-2) Configuration 2
Next, configuration 2 of the power converter 200 to which the planar antenna 100 is connected will be described. FIG. 7 is an exploded perspective view showing the configuration 2 in which the planar antenna 100 is connected to the power converter 200. However, in reality, each member shown in FIG. 7 has a laminated structure in which they are in contact with each other. In FIG. 7, since the planar antenna 100 has the same configuration as that of the first embodiment, the description thereof will be omitted.

As shown in FIG. 7, the power converter 200 includes a rectangular shield plate 141, a dielectric substrate 143 in contact with the lower surface of the shield plate 141, and a ground substrate 145 in contact with the lower surface of the dielectric substrate 143. It has. Further, the power converter 200 includes a waveguide 149 arranged in contact with the lower side of the ground substrate 145, and a band-shaped conductor pattern 165 arranged below the waveguide 149 and including the coupling element 160. It has. Specifically, it is configured as follows.

First, a notch 141a is formed at the front end portion of the shield plate 141, and the first connecting conductor 11a of the flat antenna 100 is arranged in the notch 141a. The ground substrate 145 arranged below the dielectric substrate 143 has a rectangular opening 146 formed at a position corresponding to the notch 141a of the shield plate 141, and the matching element 147 is arranged in the opening 146. ing. Further, the waveguide 149 arranged below the ground substrate 145 is formed with a hollow portion 150 penetrating in the vertical direction, and the upper opening of the hollow portion 150 coincides with the opening 146 of the ground substrate 145. It is aligned so that. Further, the coupling element 160 described above is arranged below the hollow portion 150. The second end portion 165b of the conductor pattern 165 described above is connected to the coupling element 160, and the first end portion 165a of the conductor pattern 165 is connected to the high frequency circuit 300.

In the above power converter 200, an electromagnetic wave is input from the high frequency circuit 300 to the first end portion 165a of the conductor pattern 165. The input electromagnetic wave is introduced into the hollow portion 150 of the waveguide 149 from the second end portion 165b of the conductor pattern 165 via the coupling element 160. The electromagnetic wave transmitted in the hollow portion 150 is transmitted to the first connecting conductor 11a via the matching element 147 and the dielectric substrate 143. When an electromagnetic wave is supplied to the first connecting conductor 11a, the electromagnetic wave is radiated from the antenna conductor 13 of the planar antenna 100. On the other hand, when the planar antenna 100 receives the electromagnetic wave from the antenna conductor 13, the electromagnetic wave is transmitted to the high frequency circuit 300 via the power converter 200 in the reverse order of the above.

(5) Other Antenna Devices In the above, as shown in FIGS. 5 to 7, a planar antenna 100 is connected to the power converter 200. However, the planar antenna 100 may be connected to the high frequency circuit 300 without passing through the power converter 200. Further, the flat antenna 100 may be connected to the high frequency circuit 300 via a cable such as a coaxial cable 400. FIG. 8 is a perspective view showing a configuration in which a coaxial cable is connected to the flat antenna. In FIG. 8, the first connecting conductor 11a of the flat antenna 100 is connected to the conducting wire in the coaxial cable 400. The coaxial cable 400 is connected to the high frequency circuit 300, and electromagnetic waves are transmitted and received between the planar antenna 100 and the high frequency circuit 300.

(6) Features (6-1)
In the planar antenna 100 of the first embodiment, a gap is formed between the antenna conductor 13 and the ground conductor 16 which are mutual electromagnetic wave reflecting walls by the support portions 15 extending to the left and right. Therefore, air having a relative permittivity of about 1.0 is interposed between the antenna conductor 13 and the ground conductor 16. Since the specific dielectric constant of air is smaller than that in the case where a dielectric material is interposed between the antenna conductor 13 and the ground conductor 16, the power loss of electromagnetic waves propagating between the antenna conductor 13 and the ground conductor 16 can be suppressed. Can be done.

Further, since the support portion 15 only needs to support the antenna conductor 13 with respect to the ground conductor 16, air can be interposed between the antenna conductor 13 and the ground conductor 16 with a simple configuration. Further, since the antenna conductor 13 does not need to be supported by a separate substrate, the planar antenna 100 can be reduced in size, weight, and cost.

(6-2)
In the planar antenna 100 of the first embodiment, the first support portion 15a is located on a straight line γ extending in the left-right direction through the center point β of the first antenna conductor 13a. Here, the electromagnetic wave in the first antenna conductor 13a is in a resonance state, and a standing wave node is located at the center of the first antenna conductor 13a in the resonance direction. Then, the straight line γ extends corresponding to the position of the node of the standing wave. Therefore, on the straight line γ passing near the center of the first antenna conductor 13a, the electric field strength of the electromagnetic wave is smaller than that of other regions other than the vicinity of the center. However, on the left first side 19La and the right first side 19Ra of the first antenna conductor 13a, the intensity of the electromagnetic wave tends to be higher than that in the central portion of the first antenna conductor 13a. It is considered that this is because the effective dielectric constant of the first antenna conductor 13a changes when the first antenna conductor 13a comes into contact with the air on the first side 19a, and the electromagnetic wave tends to concentrate due to this change.

Therefore, in the above-mentioned planar antenna 100, first, the right first horizontal portion 15HRa of the right first support portion 15Ra starts from the right first side 19Ra near the center in the resonance direction of the first antenna conductor 13a, and is the first antenna. It is formed so as to extend in the left-right direction on the plane of the conductor 13a. That is, in the first support portion 15a, the right first horizontal portion 15HRa extends along the plane of the first antenna conductor 13a so as to be separated from the right first side 19Ra of the first antenna conductor 13a having a large electromagnetic wave intensity. There is. As a result, it is possible to suppress the concentration of electromagnetic waves having a large electric field strength in the right first horizontal portion 15HRa. The right first vertical portion 15VRa is formed so as to extend from the end of the right first horizontal portion 15HRa toward the ground conductor 16. The left first support portion 15La is symmetrical with the right first support portion 15Ra. As a result, the influence of the first antenna conductor 13a on the electromagnetic waves caused by the provision of the first support portion 15a can be suppressed, and the antenna loss can be suppressed. Although the first antenna conductor 13a has been described above, the same can be said for the other antenna conductors 13b to 13d.

(6-3)
In the first antenna conductor 13a of the first embodiment, the left first support portion 15La and the right first support portion 15Ra are symmetrical with respect to the straight line α. Therefore, the influences of the left first support portion 15La and the right first support portion 15Ra facing each other on the electromagnetic wave in the first antenna conductor 13a are symmetrical. As a result, the resonance state of the electromagnetic wave in the first antenna conductor 13a can be maintained symmetrically with respect to the vicinity of the center. Therefore, the antenna loss due to the non-uniform resonance state can be suppressed. Although the first antenna conductor 13a has been described above, the same can be said for the other antenna conductors 13b to 13d.

(7) Modification Example A modification of the planar antenna 100 of the first embodiment will be described below. A modification similar to the following second and third embodiments will be described later as a common modification.
(7-1)
In the first embodiment, in the support portion 15 (15a to 15d), the left support portion 15L (15La to 15Ld) and the right support portion 15R (15Ra to 15Rd) extend linearly along the left-right direction. However, the left support portion 15L and the right support portion 15R may be curved or bent.

(7-2)
As for the support portion 15, at least the connection portion with the antenna conductor 13 may be located on the straight line γ, and the entire support portion 15 does not necessarily have to be located on the straight line γ.

(7-3)
In the first embodiment, the left support portion 15L (15La to 15Ld) and the right support portion 15R (15Ra to 15Rd) are symmetrical with respect to the straight line α. However, at least the connection portion between the left support portion 15L and the antenna conductor 13 and the connection portion between the right support portion 15R and the antenna conductor 13 may be symmetrical. Such an example will be described with reference to FIG. FIG. 9 is a plan view showing the arrangement relationship of the left support portion 15L and the right support portion 15R with respect to the antenna conductor 13. In FIG. 9, the connection portion between the left support portion 15L and the antenna conductor 13 and the connection portion between the right support portion 15R and the antenna conductor 13 are symmetrical with respect to the straight line α. However, the left support portion 15L and the right support portion 15R are arranged in reverse symmetry. At least, since the connecting portion between the support portion 15 and the antenna conductor 13 is symmetrical, the antenna loss due to the non-uniform resonance state of the electromagnetic wave in the antenna conductor 13 can be suppressed. Furthermore, the connection portion between the support portion 15 and the antenna conductor 13 does not need to be completely symmetrical as long as the resonance state of the electromagnetic wave in the antenna conductor 13 does not become non-uniform.

Further, for example, the left support portion 15L and the right support portion 15R may be arranged asymmetrically about the straight line α as shown in FIG. 10, for example. FIG. 10 is a plan view showing the arrangement relationship of the left support portion 15L and the right support portion 15R with respect to the antenna conductor 13. Similar to FIG. 9, the connection portion between the left support portion 15L and the antenna conductor 13 and the connection portion between the right support portion 15R and the antenna conductor 13 are symmetrical with respect to the straight line α. However, unlike FIG. 9, the left support portion 15L and the right support portion 15R are arranged asymmetrically. Furthermore, in the above embodiment, the right horizontal portion 15HR (15HRa to 15HRd) and the left horizontal portion 15HL (15HLa to 15HLd) have the same length, but may be different. However, when these lengths are the same on the left and right, the resonance state of the electromagnetic wave in the antenna conductor 13 is substantially uniform, which is preferable.

(7-4)
In the first embodiment, the connecting conductor 11 is a rectangular parallelepiped rod-shaped member. However, the shape of the connecting conductor 11 is not limited as long as it is a member connecting the antenna conductor 13, and may be, for example, a cylindrical rod-shaped member. However, when the antenna conductor 13 and the connecting conductor 11 and the like are integrally formed by punching or the like, the connecting conductor 11 is preferably a rectangular parallelepiped rod-shaped member for ease of processing.

(7-5)
In the first embodiment, the right vertical portion 15VR (15VRa to 15VRd) is a plate-shaped member extending in the vertical direction. However, the shape of the right vertical portion 15VR is not limited as long as the antenna conductor 13 can be supported via the right horizontal portion 15HR (15HRa to 15HRd). For example, the right vertical portion 15VR may be a rod-shaped member such as a rod-shaped member or a cylindrical shape. However, when the right vertical portion 15VR is bent with respect to the right horizontal portion 15HR, it is preferable that the right vertical portion 15VR is a plate-shaped member from the viewpoint of ease of processing.

<2. Second Embodiment>
Next, a planar antenna according to a second embodiment of the present invention and an antenna device including the planar antenna will be described with reference to the drawings. The second embodiment is different from the first embodiment in the configuration of the support portion, and the other configurations are almost the same as those in the first embodiment. Therefore, the same configurations are designated by the same reference numerals and the description thereof will be omitted. .. FIG. 11 is a perspective view of an antenna device including a planar antenna according to the second embodiment. FIG. 12 is an enlarged view of a region of the planar antenna of FIG. 11 including the first antenna conductor and the second antenna conductor. FIG. 13 is a cross-sectional view taken along the line AA of FIG.

(1) Configuration of Support Parts In the following, the support parts 151 that support the first to fourth antenna conductors 13a to 13d will be referred to as the first to fourth support parts 151a to 151d, respectively. As shown in FIGS. 11 to 13, the support portion 151 of the second embodiment is formed in a rod shape extending downward from the lower surface of the antenna conductor 13, and the lower end of the support portion 151 is connected to the ground conductor 16. .. As a result, a gap is formed between the antenna conductor 13 and the ground conductor 16. For example, the first support portion 151a that supports the first antenna conductor 13a is formed in a square columnar shape. As shown in FIG. 12 and the like, the first support portion 151a is arranged so that the center point β, which is the center of the first antenna conductor 13a in the front-rear direction and the left-right direction, coincides with the center of the first support portion 151a. Has been done.

Here, the reason why the first support portion 151a is arranged at the center point β will be described below. FIG. 14 is an analysis diagram showing the electric field strength distribution when the plane antenna is viewed in a plane. In FIG. 14, for example, an electromagnetic wave having a power of 1 W and 76 GHz is supplied from the first connecting conductor 11a. The electric field strength distribution of FIG. 14 is substantially the same as the electric field strength distribution of FIG. 4 of the first embodiment. That is, in FIG. 14, since the node of the standing wave of the electromagnetic wave in the first antenna conductor 13a is located in the region V, the electric field strength in the region V including the straight line γ is small. However, referring to FIGS. 4 and 14, the electric field strength is also large on the left first side 19La and the right first side 19Ra. This is because, on the left first side 19La and the right first side 19Ra, the effective dielectric constant of the first antenna conductor 13a changes when the first antenna conductor 13a comes into contact with air, and this change makes it easier for electromagnetic waves to concentrate. It is thought that this is the case.

Therefore, in the region V where the electric field strength is small, the support portion 151 is arranged at the center point β away from the left first side 19La and the right first side 19Ra where the electric field strength is large. As a result, the influence on the electromagnetic wave propagating between the first antenna conductor 13a and the ground conductor 16 caused by the provision of the first support portion 151a can be suppressed, and the antenna loss can be suppressed.

The length L61 in the front-rear direction and the length L62 in the left-right direction of the first support portion 151a are not particularly limited as long as they can support the antenna conductor 13a. However, the smaller the length L61 and the length L62, the smaller the influence of the first support portion 151a on the electromagnetic waves of the first antenna conductor 13a, which is preferable. For example, the length L61 is preferably sufficiently smaller than the length L1 in the front-rear direction of the first antenna conductor 13a, and can be, for example, 0.100 mm to 0.400 mm. For example, the length L62 is preferably sufficiently smaller than the length L2 in the left-right direction of the first antenna conductor 13a, and can be, for example, 0.100 mm to 0.400 mm.

The length L71 of the first support portion 151a is not particularly limited, but is preferably a length capable of confining electromagnetic waves between the first antenna conductor 13a and the ground conductor 16, for example. Specifically, the length L71 can be, for example, 0.080 mm to 0.250 mm.

The other second to fourth antenna conductors 13b to 13d have the same configuration, and are supported by the second to fourth support portions 151b to 151d with respect to the ground conductor 16.

(2) Features (2-1)
In the planar antenna 180 of the second embodiment, a rod-shaped support portion 151 is arranged between the antenna conductor 13 and the ground conductor 16 which are mutual electromagnetic wave reflecting walls. Therefore, air having a relative permittivity of about 1.0 is interposed between the antenna conductor 13 and the ground conductor 16. Since air has a smaller relative permittivity than the dielectric material, it is possible to suppress the power loss of electromagnetic waves propagating between the antenna conductor 13 and the ground conductor 16.

Further, air can be interposed between the antenna conductor 13 and the ground conductor 16 with a simple configuration in which the antenna conductor 13 is supported by the support portion 151. Further, since the antenna conductor 13 does not need to be supported by a separate substrate, the planar antenna 180 can be reduced in size, weight, and cost.

(2-2)
In the planar antenna 180 of the second embodiment, the first support portion 151a is located at the center point β of the first antenna conductor 13a. Since the center point β is located away from the first side 19a of the first antenna conductor 13a having a large standing wave node and a large electric field strength, the electric field strength of the electromagnetic wave is higher than that of other regions other than the vicinity of the center. small. Therefore, by providing the first support portion 151a at the above-mentioned position, the influence of the first support portion 15a on the electromagnetic wave caused by the provision of the first support portion 15a can be suppressed, and the antenna loss can be suppressed. Although the first antenna conductor 13a has been described above, the same can be said for the other antenna conductors 13b to 13d.

(2-3)
Since the support portion 151 supports the center point β of the antenna conductor 13, the antenna conductor 13 can be supported in a well-balanced and stable manner.

(3) Modification Example A modification of the plane antenna 180 of the second embodiment will be described below. A modification similar to the first and third embodiments will be described later as a common modification.
(3-1)
In the second embodiment, the support portion 151 is arranged at the center point β. However, it may be arranged at any position of the straight line γ that passes through the center point β and extends in the left-right direction. Further, for example, the arrangement position of the support portion 151 on the straight line γ may be different depending on the antenna conductors 13a to 13d.

(3-2)
In the second embodiment, only one support portion 151 is provided for one antenna conductor 13. However, a plurality of support portions 151 may be provided for one antenna conductor 13. For example, support portions 151 may be provided at a plurality of locations on the straight line γ. In addition, the four antenna conductors 13a to 13d need only be supported by the ground conductor 16 as a whole, and it is not necessary to provide the support portions 151 for all the antenna conductors 13. For example, the support portion 151 may be provided on any of the adjacent antenna conductors 13.

(3-3)
In the second embodiment, the support portion 151 has a square columnar shape, but the shape of the support portion 151 is not limited as long as it can support the antenna conductor 13. For example, the support portion 151 may have a columnar shape, an elliptical shape, a polygonal shape, or the like.

<3. Third Embodiment>
Next, a planar antenna according to a third embodiment of the present invention and an antenna device including the planar antenna will be described with reference to the drawings. The third embodiment is different from the first embodiment in the configuration of the support portion, and the other configurations are almost the same as those in the first embodiment. Therefore, the same configurations as those in the first embodiment are designated by the same reference numerals. FIG. 15 is a perspective view of an antenna device including a planar antenna according to a third embodiment. FIG. 16 is an enlarged view of a region of the planar antenna of FIG. 15 including the first antenna conductor and the second antenna conductor. FIG. 17 is a cross-sectional view taken along the line AA of FIG.

(1) Configuration of Support Parts In the following, the support parts 152 that support the first to fourth antenna conductors 13a to 13d will be referred to as the first to fourth support parts 152a to 152d, respectively. As shown in FIGS. 15 to 17, the support portion 15 of the third embodiment has a left support portion 15L having a left horizontal portion 15HL and a left vertical portion 15VL, and a right support having a right horizontal portion 15HR and a right vertical portion 15VR. It is formed from a portion 15R. However, the support portion 152 of the third embodiment is formed so as to extend from the left and right opposite sides of the antenna conductor 13 to the ground conductor 16, whereby a gap is formed between the antenna conductor 13 and the ground conductor 16. It is formed.

For example, the first antenna conductor 13a is supported by the first support portion 152a including the flat left first support portion 152La and the right first support portion 152Ra with respect to the ground conductor 16. The left first support portion 152La is connected to a central portion where the left first side 19La of the first antenna conductor 13a and the straight line γ intersect, and extends toward the ground conductor 16. Similarly, the right first support portion 152Ra is connected to the central portion where the right first side 19Ra and the straight line γ intersect, and extends toward the ground conductor 16. The connection portion between the left first support portion 152La and the left first side 19La and the connection portion between the right first support portion 152Ra and the right first side 19Ra are symmetrical with respect to the straight line α.

Here, the reason why the left first support portion 152La is connected to the center of the left first side 19La and the right first support portion 152Ra is connected to the center of the right first side 19Ra will be described below. FIG. 18 is an analysis diagram showing the electric field strength distribution when the plane antenna is viewed in a plane. In FIG. 18, for example, an electromagnetic wave having a power of 1 W and 76 GHz is supplied from the first connecting conductor 11a. The electric field strength distribution of FIG. 18 is substantially the same as the electric field strength distribution of FIG. 4 of the first embodiment. That is, in FIG. 18, since the node of the standing wave of the electromagnetic wave in the first antenna conductor 13a is located in the region V, the electric field strength in the region V including the straight line γ is small. Therefore, by providing the left first support portion 152La and the right first support portion 152Ra at the portion of the left first side 19La and the right first side 19Ra that intersects the straight line γ, the first support portion 152a is provided. It is possible to suppress the influence on the electromagnetic wave propagating between the first antenna conductor 13a and the ground conductor 16 and suppress the antenna loss.

The length L65 in the front-rear direction and the length L66 in the left-right direction of the first support portion 152a are not particularly limited as long as they can support the antenna conductor 13a. However, the smaller the length L65 and the length L66, the smaller the influence of the first support portion 152a on the electromagnetic waves of the first antenna conductor 13a, which is preferable. For example, the length L65 is preferably sufficiently smaller than the length L1 in the front-rear direction of the first antenna conductor 13a, and can be, for example, 0.100 mm to 0.400 mm. The length L66 can be, for example, 0.020 mm to 0.200 mm.

The length L72 of the first support portion 152a is not particularly limited, but is preferably a length capable of confining electromagnetic waves between the first antenna conductor 13a and the ground conductor 16, for example. Specifically, the length L72 can be, for example, 0.080 mm to 0.250 mm.

The other second to fourth antenna conductors 13b to 13d have the same configuration, and are supported by the second to fourth support portions 151b to 151d with respect to the ground conductor 16.
(2) Features (2-1)
In the third embodiment, similarly to the second embodiment, a support portion 152 extending vertically is arranged between the antenna conductor 13 and the ground conductor 16. Therefore, since air having a relative permittivity of about 1.0 is interposed between the antenna conductor 13 and the ground conductor 16, the power loss of the electromagnetic wave propagating between the antenna conductor 13 and the ground conductor 16 is suppressed. be able to.

Further, as in the second embodiment, the planar antenna 190 can be reduced in size, weight, and cost by a simple configuration.

(2-2)
In the planar antenna 190 of the third embodiment, the support portion 152 is located at the intersection of the first side 19 of the antenna conductor 13 and the straight line γ. The straight line γ extends corresponding to the position of the node of the standing wave, and the electric field strength of the electromagnetic wave on the straight line γ is smaller than that in other regions other than the vicinity of the center. Therefore, the influence of the antenna conductor 13 on the electromagnetic wave caused by providing the support portion 15 at the above-mentioned position can be suppressed, and the antenna loss can be suppressed.

(2-3)
In the first antenna conductor 13a of the third embodiment, the left first support portion 152La and the right first support portion 152Ra are symmetrical with respect to the straight line α. Therefore, as described in the first embodiment, the antenna loss due to the non-uniform resonance state of the electromagnetic wave in the first antenna conductor 13a can be suppressed. Although the first antenna conductor 13a has been described above, the same can be said for the other antenna conductors 13b to 13d.

(2-4)
Since each of the support portions 15 supports the vicinity of the center of the first side 19 of the antenna conductor 13 so as to face each other, the antenna conductor 13 can be supported in a well-balanced and stable manner.

(3) Modification Example A modification of the planar antenna 190 of the third embodiment will be described below. A modification similar to the first and second embodiments will be described later as a common modification.

(3-1)
In the third embodiment, the left first support portion 152La and the right first support portion 152Ra are symmetrical with respect to the straight line α. However, the left first support portion 152La and the right first support portion 152Ra do not need to be completely symmetrical with respect to the straight line α as long as the resonance state of the electromagnetic wave in the antenna conductor 13 does not become non-uniform. ..

(3-2)
In the third embodiment, the support portion 152 has a flat plate shape, but the shape is not limited as long as the antenna conductor 13 can be supported. For example, the support portion 152 may have a square columnar shape, a columnar shape, an elliptical shape, a polygonal shape, or the like.

<4. Modification example>
Although the first to third embodiments of the present invention have been described above, the present invention is not limited to the above embodiments, and various modifications such as the following can be made without departing from the spirit of the present invention. .. The gist of the following modifications can be combined as appropriate. The specific modification examples in each embodiment have been described in each embodiment, but here, the modification common to the first to third embodiments will be described.

<4-1>
In the first to third embodiments, the support portions 15, 151, and 152 are located on the straight line γ, but do not necessarily have to be located on the straight line γ. For example, the support portions 15, 151, and 152 may be located near the center of the antenna conductor 13 in which the node of the standing wave formed by the electromagnetic wave is located. The term "near the center" may be any region of the antenna conductor 13 having a small electric field strength, and includes not only the center point β of the antenna conductor 13 but also the center point β and its vicinity. Further, the support portions 15, 151, and 152 do not necessarily have to be located near the center of the antenna conductor 13 as long as they are located on a straight line extending in the left-right direction through the node of the standing wave of the electromagnetic wave in the antenna conductor 13. ..

<4-2>
In the above embodiment, the antenna conductor 13 is supported by the support portion 15 so as to have a gap between the antenna conductor 13 and the ground conductor 16. However, the antenna conductor 13 may be supported by the connecting conductor 11. In this case, the support portion is provided in the region of the connecting conductor 11 where the electric field strength is small. The region of the connecting conductor 11 having a small electric field strength is the region VI shown in FIGS. 4, 14 and 18. The region VI is located in the central portion of the connecting conductor 11 having a length L5 in the front-rear direction of 1 / 2λg. 19 to 21 show a configuration in which support portions 153 (153a to 153d), 154 (154a to 154d), and 155 (155a to 155d) are provided in this region VI. FIG. 19 is a perspective view of the antenna device when the support portion of the first embodiment is provided on the connecting conductor. FIG. 20 is a perspective view of the antenna device when the support portion of the second embodiment is provided on the connecting conductor. FIG. 21 is a perspective view of the antenna device when the support portion of the third embodiment is provided on the connecting conductor.

By providing the support portion 153 (FIG. 19), the support portion 154 (FIG. 20), and the support portion 155 (FIG. 21) in the region VI of the connecting conductor 11 in this way, the support portions 153, 154, and 155 are connected to the connecting conductor 11. The effect on electromagnetic waves can be suppressed. As a result, the influence of the connecting conductor 11 on the electromagnetic waves in the antenna conductor 13 can be suppressed, and the antenna loss can be suppressed. Further, since the support portion 15 is not provided on the antenna conductor 13, it is possible to further suppress the influence of the electromagnetic wave in the antenna conductor 13 and the occurrence of antenna loss. It is sufficient that the antenna conductors 13 can be supported by the support portions 153, 154, and 155, and it is not necessary to provide the support portions 15 on all the connecting conductors 11 (11a to 11d).

<4-3>
In the above embodiment, the length L1 of the antenna conductor 13 in the front-rear direction is λg / 2. However, the length L1 is not limited to λg / 2 as long as the electromagnetic wave is in a resonance state in the front-rear direction of the antenna conductor 13. For example, the length L1 of the antenna conductor 13 in the front-rear direction may be (λg / 2) × l (l is an integer of 2 or more). Similarly, in the above embodiment, the length L5 of the connecting conductor 11 in the front-rear direction is λg / 2. However, similarly to the above, the length L5 is not limited to λg / 2, and may be (λg / 2) × m (m is an integer of 2 or more).

<4-4>
In the above embodiment, the antenna conductor 13 has a rectangular shape, but may have a rectangular shape such as a square shape or a trapezoidal shape other than the rectangular shape shown in FIGS. 22 and 23. Further, it is preferable that the antenna conductor 13 has a pair of sides facing each other in the resonance direction parallel to each other. In addition, the antenna conductor 13 may have a shape including a polygonal shape and an arc rather than a quadrangle as long as a set of opposite sides in the resonance direction are parallel to each other.

<4-5>
In the above embodiment, the ground conductor 16 is exemplified as the opposing conductor facing the antenna conductor 13. However, the opposing conductor does not have to be grounded, and may be, for example, a conductor having a predetermined potential. However, it is preferable to use the ground conductor 16 which is grounded because the electric field of the electromagnetic wave can be stabilized.

<4-6>
In the above embodiment, the planar antenna 100 includes four antenna conductors 13. However, the number of antenna conductors 13 is not limited to this, and may be one or five or more. Similarly, the number of connecting conductors 11 is not limited to four, and may be one or five or more.

<4-7>
In the above embodiment, the support portions 15, 151, and 152 are provided on all the antenna conductors 13. However, if a gap can be provided between the antenna conductor 13 and the ground conductor 16, it is not necessary to provide the support portions 15, 151, 152 in all the antenna conductors 13, and the number of the support portions 15, 151, 152. Is not limited.

<4-8>
In the above embodiment, an example in which a plurality of antenna conductors 13 are arranged in a row is shown. However, a plurality of antenna conductors may be arranged in a plurality of rows. Such an example will be described with reference to FIGS. 24A to 24C. 24A to 24C are explanatory views when a plurality of antenna conductors are arranged in a plurality of rows.

The planar antenna 1011 shown in FIG. 24A includes a set of three rows 900a-900c (900). One row of sets 900 includes four antenna conductors 13, four connecting conductors 11, and four sets of left support 15L (15HL and 15VL) and right support 15R (15HR and 15VR) along the front-back direction. Is arranged with respect to the ground conductor 16. Each antenna conductor 13 is supported by support portions 15 provided on the left and right. Then, the support portions 15 of the antenna conductors 13 adjacent to each other in the left-right direction are connected to each other. For example, the antenna conductor 13 of the set 900a is supported by the left horizontal portion 15HL and the right horizontal portion HR, and the left vertical portion 15VL and the right vertical portion 15VR. The right horizontal portion 15HR of the antenna conductor 13 of the set 900a and the left horizontal portion 15HL of the antenna conductor 13 of the set 900b are connected to each other.

In the planar antenna 1012 shown in FIG. 24B, unlike the planar antenna 1011 shown in FIG. 24A, the support portions 15 (15HL, 15HR, 15VL, 15VR) of the antenna conductors 13 adjacent to the left and right are not connected to each other. Other configurations are the same as those of the planar antenna 1011.

In the flat antenna 1013 shown in FIG. 24C, unlike the flat antenna 1011 shown in FIG. 24A, only the antenna conductor 13 in the left end set 900a and the right end set 900c in the left-right direction has the left vertical portion 15VL and the right vertical portion, respectively. It has 15VR. The left horizontal portion 15HL and the right horizontal portion HR are connected to the antenna conductors 13 adjacent to the left and right. No vertical portion is provided between the antenna conductors 13 adjacent to the left and right. Other configurations are the same as those of the planar antenna 1011.

<4-9>
In the antenna device, the planar antennas 100, 180, 190 of the first to third embodiments may be combined.

Hereinafter, examples of the present invention will be described. However, the present invention is not limited to the following examples. Then, (1) the electric field strength distribution and directivity were acquired by simulation. In addition, (2) length L9 was evaluated. First, (1) evaluation of the electric field strength distribution and directivity will be described.

(1) Evaluation of electric field strength distribution and directivity (1-1) Planar antenna of Examples 1-1 to 1-3, ideal plane antenna (a) Configuration As a plane antenna of Examples 1-1 to 1-3 , Antennas having the same configurations as the planar antennas 100, 180, and 190 of the first to third embodiments described above were prepared. Further, for comparison with these examples, a plane antenna in an ideal state called an ideal plane antenna was prepared. The ideal plane antenna is shown in FIGS. 25 to 27. FIG. 25 is a perspective view of an antenna device including an ideal plane antenna. FIG. 26 is an enlarged view of a region of the ideal plane antenna of FIG. 25 including the first antenna conductor and the second antenna conductor. FIG. 27 is a cross-sectional view taken along the line AA of FIG. 26.

As shown in FIGS. 25 to 27, the ideal planar antenna 195 is a component of the antenna device 4000, and does not include the support portion 15 in the planar antenna 100 of the first embodiment. That is, the antenna conductor 13 and the connecting conductor 11 face each other with the ground conductor 16 via air without passing through the support portion 15. It should be noted that a configuration in which the support portion 15 is not provided is considered to have the least influence on the electromagnetic waves in the antenna conductor 13, and is therefore referred to as an ideal plane antenna. Since other configurations are the same as those of the planar antenna 100 of the first embodiment, the description thereof will be omitted.

In the planar antenna and the ideal planar antenna 195 of Examples 1-1 to 1-3, the dimensions related to each antenna conductor 13 are as shown in Table 1 below.

Subsequently, from the first connecting conductor 11 to the planar antennas of Examples 1-1 to 1-3 (corresponding to the planar antennas 100, 180, 190 of the first to third embodiments) and the ideal planar antenna 195. An electromagnetic wave with a power of 1 W and a frequency of 76 GHz was supplied. The electric field strength distribution and directivity of each planar antenna are as follows.

(B) Electric field strength distribution FIGS. 4, 14, and 18 are the electric field strength distributions of the planar antennas of Examples 1-1 to 1-3, respectively. FIG. 28 shows the electric field strength distribution of the ideal plane antenna 195. Examples 1-1 to 1-3 have already been described with reference to FIGS. 4, 14 and 18, but similarly to these examples, the ideal plane antenna 195 also has a standing wave as shown in FIG. 28. The electric field strength was the lowest in the region V where the nodes were located. On the other hand, in each plane antenna, the electric field strength was the largest in the regions I to IV where the antinodes of the standing waves were located.

(C) Directivity FIGS. 29 to 31 show the directivity (gain distribution for each angle) of the planar antennas of Examples 1-1 to 1-3. FIG. 32 shows the directivity of the ideal plane antenna. In FIGS. 29 to 32, the solid line is the directivity in the front-rear direction and the directivity in the left-right direction of the antenna conductor 13. The directivity in the front-rear direction is, for example, the gain in the front-rear direction when the antenna conductor 13 is viewed sideways from the left-right direction in FIG. On the other hand, the gain in the left-right direction is, for example, the gain in the left-right direction when the antenna conductor 13 is viewed from the front-rear direction in FIG.

Specifically, in the solid line, in the plane passing through the straight line α and perpendicular to the antenna conductor, the center point β is set to 0 °, the gain is acquired from here to + 90 ° with the front side as a plus, and the rear side is minus from the center point β. The gain is acquired up to -90 °. On the other hand, in the broken line, in the plane passing through the straight line γ and perpendicular to the antenna conductor 13, the center point β is set to 0 °, the gain is acquired from here to + 90 ° with the left side as plus, and the gain is obtained from the center point β with the right side as minus 90. The gain is obtained up to °.

According to FIGS. 29 to 32, the peak gains of the planar antenna and the ideal planar antenna 195 of Examples 1-1 to 1-3 are as shown in Table 2 below.

(1-2) Comparative Example 1
(A) Configuration As a comparative example, the planar antenna 5000 of Comparative Example 1 has the configuration of FIG. 33. FIG. 33 is a perspective view of an antenna device including the planar antenna of Comparative Example 1. FIG. 34 is a cross-sectional view taken along the line AA of FIG. 33. In the planar antenna 5000 of Comparative Example 1, in the planar antenna 100 of the first embodiment, the antenna conductor 13 and the connecting conductor 11 face the ground conductor 16 via a dielectric material. Therefore, the planar antenna 5000 of Comparative Example 1 does not include a support portion. Other configurations are the same as those of the planar antennas 100, 180, and 190 of the first to third embodiments, and thus the description thereof will be omitted.

Further, similarly to Examples 1-1 to 1-3, an electromagnetic wave having a power of 1 W and a frequency of 76 GHz was supplied from the first connecting conductor 11 to the planar antenna 5000 of Comparative Example 1. The electric field strength distribution and directivity of the planar antenna 5000 of Comparative Example 1 are as follows.

(B) Electric field strength distribution FIG. 35 shows the electric field strength distribution of the planar antenna 5000 of Comparative Example 1. Also in the planar antenna 5000 of Comparative Example 1, the electric field strength was the smallest in the region V, which is the central portion of the antenna conductor 13, and the electric field strength was the largest in the regions I to IV.

(C) Directivity The directivity was acquired for the planar antenna 5000 of Comparative Example 1. FIG. 36 shows the directivity of the planar antenna 5000 of Comparative Example 1. As shown in FIG. 36, in the planar antenna 5000 of Comparative Example 1, the peak gain was 10.9 dB.

(1-3) Discussion The following points were found from the electric field strength distribution and directivity. In Examples 1-1 to 1-3 (corresponding to the planar antennas 100, 180, 190 of the first to third embodiments), as shown in FIGS. 4, 14, and 18, the antenna conductor 13 in the region V Support portions 15, 151, and 152 are arranged in the vicinity of the center including the straight line γ. The region V is a region where the electric field strength is weak as described above. In this case, as shown above, in Examples 1-1 to 1-3, the peak gain is higher than 10.9 dB in Comparative Example 1. In particular, in the first embodiment (the planar antenna 100 of the first embodiment), the same peak gain as the ideal planar antenna 195 shown in FIG. 32 can be secured. Further, in the first and second embodiments (the planar antenna 180 of the second embodiment), although the peak gain is lower than that of the ideal planar antenna 195, the same peak gain can be secured. Further, also in Example 1-3 (planar antenna 190 of the third embodiment), a flat antenna having a peak gain higher than that of Comparative Example 1 and having a high peak gain to some extent can be obtained. Therefore, in Examples 1-1 to 1-3, the influence on the electromagnetic wave propagating between the antenna conductor 13 and the ground conductor 16 caused by providing the support portions 15, 151, and 152 is suppressed. As a result, it can be seen that the antenna loss can be suppressed.

(2) Evaluation of Length L9 Next, using Examples 2-1 and 2-2, the optimum value of the length L9 related to the length of the support portion 15 was evaluated. As shown in FIG. 3 of the first embodiment, the length L9 is the distance from the straight line α passing through the center point β of the antenna conductor 13 to the right end of the right horizontal portion 15HR (15HRa to 15HRd), or , The distance from the straight line α to the left end of the left horizontal portion 15HL (15HLa to 15HLd). This point will be described below with reference to FIGS. 37A and 37B. 37A and 37B are explanatory views showing the electric field strength distributions of the planar antennas 1001 and 1002 of Examples 2-1 and 2-2 shown below, respectively. In FIGS. 37A and 37B, the electric field strength distribution in the cross section of the portion where the support portion 15 is provided is shown in the planar antennas 1001 and 1002, respectively.

(2-1) Examples 2-1 and 2-2
(A) Configuration As shown in FIGS. 37A and 37B, the planar antennas 1001 and 1002 of Examples 2-1 and 2-2 of the present invention have a length L9 in the planar antenna 100 of the first embodiment described above. L10 is as shown in Table 3 below. Since other configurations are the same as those of the planar antenna 100 of the first embodiment, the description thereof will be omitted.

An electromagnetic wave having a power of 1 W and 76 GHz was supplied from the first connecting conductor 11 to the planar antennas 1001 and 1002 of Examples 2-1 and 2-2 described above. The electric field strength distribution and directivity of the planar antennas 1001 and 1002 of Examples 2-1 and 2-2 are as follows.

(B) Electric Field Strength Distribution As shown in FIG. 37A, in the planar antenna 1001 of Example 2-1 the entire region VII from the right end to the left end of the support portion 15 (15L, 15R) has one electric field strength. It is a weak area.

Further, in the planar antenna 1002 of the second embodiment, as shown in FIG. 37B, the region from the right end portion to the left end portion of the support portion 15 (15L, 15R) is the region VIII and two regions. Includes region VX. Region VIII is the region where the antenna conductor 13 is located. The right support portion 15R and the left support portion 15L are located in each of the two regions VX. The lateral lengths of region VIII and the two regions VX are approximately the same. That is, the left-right length L102 of the region VIII and the left-right length L101 of the two regions VX are substantially the same. The region VIII and each of the two regions VX are regions in which the electric field strength is weak.

(C) Directivity The planar antenna 1001 of Example 2-1 had a peak gain of about 12.5 dB. Similarly, the planar antenna 1002 of Example 2-2 also had a peak gain of about 12.5 dB.

(2-2) Consideration As shown in FIGS. 37A and 37B, in the planar antennas 1001 and 1002 of Examples 2-1 and 2-2, L10 is λg × 1/2 (about 1.8 mm) and λg ×, respectively. It is 3/2 (about 5.6 mm), and L10 = λg × (n / 2) (n is an odd number of 1 or more). Furthermore, in the planar antennas 1001 and 1002 of Examples 2-1 and 2-2, L9 is λg × 1/4 (about 0.9 mm) and λg × 3/4 (about 2.8 mm), respectively, and L9. = Λg × (o / 4) (o is an odd number of 1 or more). In this case, as shown in FIG. 33, the electric field strength is weak in the regions VII, VIII, and VX from the right end portion to the left end portion of the support portion 15. The peak gains of the planar antennas 1001 and 1002 of Examples 2-1 and 2-2 were about 12.5 dB, which were excellent. That is, it was found that the influence on the electromagnetic wave propagating between the antenna conductor 13 and the ground conductor 16 caused by the provision of the support portion 15 was suppressed. Therefore, the length L10 is preferably λg × (n / 2) (n is an odd number of 1 or more), and the length L9 is λg × (o / 4) (o is an odd number of 1 or more). It turned out to be preferable.

11a to 11d: Connecting conductors 13a to 13d: Antenna conductors 15a to 15d: Support part 15HL: Left horizontal part 15HR: Right horizontal part 15VL: Left vertical part 15VR: Right vertical part 16: Ground conductor 100: Flat antenna 180: Flat antenna 190: Horizontal antenna 195: Ideal horizontal antenna 200: Power converter 300: High frequency circuit

Claims (3)

A plurality of antenna conductors that transmit and receive electromagnetic waves and form a reflection wall of the electromagnetic waves,
A connecting conductor that connects the plurality of antenna conductors,
The facing conductors facing the plurality of antenna conductors and the connecting conductors and forming the electromagnetic wave reflecting wall,
A support portion that supports the connecting conductor so that a gap is formed between the plurality of antenna conductors and the opposing conductor.
With
Assuming that the in-tube wavelength of the electromagnetic wave in the antenna conductor is λg, the length of the connecting conductor is λg / 2 or (λg / 2) × m (m is an integer of 2 or more).
The support portion is located at a position at λg / 4 or λg / 4 + (λg / 2) × (mn) (n is an integer up to m-1) from the longitudinal end of the connecting conductor. A planar antenna that connects to the opposite conductor. The planar antenna according to claim 1 and
A power converter that converts the power of electromagnetic waves transmitted and received by the flat antenna, and
An antenna device equipped with. The antenna device according to claim 2, further comprising a high frequency circuit connected to the power converter.

Images