JP6282469B2 - antenna - Google Patents

Description

  The present invention relates to an antenna.

An antenna that is installed on a ceiling or a wall and used indoors is required to have a thin planar structure from the viewpoint of installation and landscape.
By using an EBG (Electromagnetic Band Gap) structure using a metamaterial technique as a reflector, the antenna can be lowered.

  Patent Document 1 discloses a radio communication system configured to secondarily radiate a radio wave primarily emitted from a transmission-side device to a desired area by reflection using a reflector that controls the phase of a reflected wave. The reflection plate has a reflection characteristic set so as to reflect the radio wave primarily radiated from the transmission side device as a plane wave having an equal phase directed in a direction different from a reflection angle in the case of specular reflection. A communication system is described.

JP 2010-62689 A

By the way, when a planar antenna is used indoors, it is inclined (tilted) from a direction perpendicular to the plane of the planar structure because of the relationship between the position where the antenna is installed and the position where radio waves are transmitted and received from the antenna. It is required that radio waves are transmitted and received.
An object of the present invention is to provide a low-profile antenna that can transmit and receive radio waves in a direction inclined from a direction perpendicular to a reflector.

For this purpose, an antenna to which the present invention is applied is arranged at a first predetermined distance in a direction perpendicular to a plane made of a conductive material and a conductor made of a conductive material. A plurality of conductor patches having a region where the ratio of the surface area facing the conductor per predetermined area varies in a predetermined direction, and a plurality of conductor patches in a direction perpendicular to the plane including the conductor. provided in the second predetermined distance, and a radiating element for transmitting and receiving radio waves through the feed point has a feed point, radiating elements, side ratio of the surface area of the plurality of conductor patches is large It is characterized by having directivity for transmission / reception of radio waves in a direction inclined to .
In such an antenna, in a direction orthogonal to the plane including the conductor, provided at a predetermined third distance from the plurality of conductor patches, and having another feeding point and radiating through the other feeding point. It further includes another radiating element that transmits and receives a radio wave having a polarization that intersects with the polarization of the radio wave that is transmitted and received by the element. It has the directivity with respect to transmission / reception of .
Thereby, it can be set as the antenna of polarization sharing.

Further, the change in the ratio of the surface area facing the conductor in the aforementioned region of the plurality of patches may be a change in the surface area of the patch included in this region.
In addition, the interval between the plurality of patches may be different between a predetermined direction and a direction orthogonal to the predetermined direction.
Thereby, the directivity of both polarized waves can be controlled separately.

  On the other hand, the change in the ratio of the surface area facing the conductor in the aforementioned region of the plurality of patches may be a change in the distance between the patches included in the aforementioned region.

Furthermore, the center of either or both of the radiating element and the other radiating element may be arranged so as to be deviated from the center of the aforementioned region in a predetermined direction.
As a result, the direction of radio waves that can be transmitted and received can be increased from the direction perpendicular to the reflector.

The plurality of conductor patches are provided so as to exclude a portion facing either or both of the radiating element and the other radiating element.
This facilitates power feeding to the radiating element or other radiating elements.

  ADVANTAGE OF THE INVENTION According to this invention, the low attitude | position antenna which can transmit / receive an electromagnetic wave in the direction inclined from the perpendicular | vertical direction of the reflecting plate can be provided.

It is a perspective view which shows an example of the whole structure of the antenna with which 1st Embodiment is applied. It is the top view and sectional drawing of the antenna with which 1st Embodiment is applied. (A) is a plan view of the antenna, (b) is a cross-sectional view taken along line IIb-IIb in (a) of the antenna, and (c) is a cross-sectional view taken along line IIc-IIc in (a) of the antenna. It is a figure which shows the structure of the conductor patch and dipole element in the reflecting plate of the antenna with which 1st Embodiment is applied. (A) is a structure of the conductor patch in a reflecting plate, (b) is a figure which shows the structure of a dipole element. It is a perspective view which shows an example of the whole structure of the antenna with which 2nd Embodiment is applied. It is the top view and sectional drawing of an antenna with which 2nd Embodiment is applied. (A) is a plan view of the antenna, (b) is a cross-sectional view taken along line Vb-Vb in (a) of the antenna, and (c) is a cross-sectional view taken along line Vc-Vc in (a) of the antenna. It is a figure which shows the structure of the conductor patch and dipole element in the reflecting plate of the antenna with which 2nd Embodiment is applied. (A) is a structure of the conductor patch in a reflecting plate, (b) is a figure which shows the structure of a dipole element. It is a figure which shows the directivity in the vertical direction (in a vertical surface) of the antenna 1 with which 2nd Embodiment is applied, and its frequency (f) dependence. (A) Directivity of vertical polarization element at f = 0.94f ₀ , (b) Directivity of vertical polarization element at f = f ₀ , (c) Vertical polarization at f = 1.06f ₀ (D) is the directivity of the horizontal polarization element at f = 0.94f ₀ , (e) is the directivity of the horizontal polarization element at f = f ₀ , and (f) is f = 1.06f. The directivity of the horizontal polarization element at _zero . It is a figure which shows the relationship between the reflection phase difference of the reflected wave with respect to the incident wave in the reflecting plate comprised with the EBG structure, and the space | interval d of a conductor patch. (A) is a figure explaining the space | interval d of a conductor patch, (b) is a figure explaining the incident wave and reflected wave with respect to a reflecting plate, (c) is the reflection phase difference with respect to the frequency f, and the space | interval d of a conductor patch. It is a figure which shows a relationship. It is a perspective view which shows an example of the whole structure of the antenna with which 3rd Embodiment is applied. It is a top view of the antenna with which 3rd Embodiment is applied. It is a figure which shows the directivity in the orthogonal | vertical direction (in a vertical surface) of the antenna with which 3rd Embodiment is applied, and its frequency (f) dependence. (A) Directivity of vertical polarization element at f = 0.94f ₀ , (b) Directivity of vertical polarization element at f = f ₀ , (c) Vertical polarization at f = 1.06f ₀ (D) is the directivity of the horizontal polarization element at f = 0.94f ₀ , (e) is the directivity of the horizontal polarization element at f = f ₀ , and (f) is f = 1.06f. The directivity of the horizontal polarization element at _zero . It is a figure explaining shifting and arranging the center of a dipole element from the center of a reflector in the perpendicular direction. (A) is a case where the center of the dipole element is shifted from the center of the reflecting plate to the positive side in the vertical direction, (b) is a case where the center of the dipole element is placed at the center of the reflecting plate, and (c) is The case where the center of the dipole element is shifted from the center of the reflector to the negative side in the vertical direction is shown. It is a figure which shows the relationship between the position R of the dipole element center with respect to the reflector center, and tilt angle (theta). It is a top view of the antenna with which 4th Embodiment is applied. It is a figure which shows the directivity in the orthogonal | vertical direction (in a vertical surface) of the antenna with which 4th Embodiment is applied. (A) is the directivity of the vertical polarization element at f = f ₀ , and (b) is the directivity of the horizontal polarization element at f = f ₀ . It is a top view of the antenna with which 5th Embodiment is applied. It is a figure which shows the directivity in the vertical direction (in a vertical surface) of the antenna with which 5th Embodiment is applied. (A) is the directivity of the vertical polarization element at f = f ₀ , and (b) is the directivity of the horizontal polarization element at f = f ₀ . It is a top view of the antenna with which 6th Embodiment is applied. It is a figure which shows the directivity in the orthogonal | vertical direction (in a vertical surface) of the antenna with which 6th Embodiment is applied. (A) is the directivity of the vertical polarization element at f = f ₀ , and (b) is the directivity of the horizontal polarization element at f = f ₀ . It is a top view of the antenna with which 7th Embodiment is applied. It is a figure which shows the directivity in the orthogonal | vertical direction (in a vertical surface) of the antenna with which 7th Embodiment is applied. (A) is the directivity of the vertical polarization element at f = f ₀ , and (b) is the directivity of the horizontal polarization element at f = f ₀ . It is a perspective view which shows an example of the whole structure of the antenna with which 8th Embodiment is applied. It is a perspective view which shows an example of the whole structure of the antenna with which 9th Embodiment is applied. It is a top view of the antenna with which 9th Embodiment is applied. It is a figure which shows the directivity of the vertical polarization element of the antenna with which 9th Embodiment is applied. (A) is the directivity of the vertical polarization element in the xz plane, (b) is the directivity of the vertical polarization element in the yz plane, and (c) is the φ _{45 °} -z plane. The directivity of the vertical polarization element.

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
[First Embodiment]
FIG. 1 is a perspective view showing an example of the overall configuration of an antenna 1 to which the first embodiment is applied.
As shown in FIG. 1, the antenna 1 is arranged in parallel with a conductor 11 made of a conductive material and a predetermined distance (distance L3 in FIG. 2 described later) in a direction orthogonal to the plane including the conductor 11. A predetermined distance in a direction orthogonal to the plane including the conductor 11 from the plurality of conductor patches 12 and the reflector 10 including the plurality of conductor patches 12 made of the conductive material formed (FIG. 2 to be described later) And a dipole element 20 as an example of a radiating element provided at a distance L2).
The reflector 10 includes an conductor 11 and a plurality of conductor patches 12 to form an EBG structure.
In FIG. 1, in order to distinguish the conductor patch 12 and the dipole element 20 in the reflector 10, the dipole element 20 is provided with a halftone dot. The same applies to the other drawings.
It is assumed that the conductor 11 of the reflecting plate 10 is a rectangle, and the direction from the lower side to the upper side in FIG. 1 is a vertical direction and the direction from the left side to the right side is a horizontal direction along the sides of the rectangle.
The plurality of conductor patches 12 are configured such that the surface area (surface area) of the conductor patch 12 changes in the vertical direction, as will be described later with reference to FIG. That is, the plurality of conductor patches 12 are set so that the surface area becomes smaller from the upper part to the lower part in the vertical direction.
Here, each of the plurality of conductor patches 12 may be referred to as a conductor patch 12, and the plurality of conductor patches 12 may be collectively referred to as a conductor patch 12.

The dipole element 20 includes a pair of element portions 20a and 20b in the vertical direction. The dipole element 20 transmits and receives vertically polarized waves. The direction of polarization (vertical polarization) coincides with the direction in which the surface area decreases in the plurality of conductor patches 12.
The dipole element 20 has a feeding point at the center of the element portions 20a and 20b (see FIG. 3) and transmits and receives radio waves. Here, the description of the method of feeding power to the dipole element 20 is omitted.

When the antenna 1 transmits radio waves, when the dipole element 20 is supplied with power, the angle θ (tilt) extends from the direction of the vertical line (perpendicular direction) perpendicular to the reflector 10 to the side with the larger surface area of the conductor patch 12. The main beam is emitted in a direction (radiation direction) inclined (angle θ).
The same applies to the case of receiving radio waves due to the reversibility of the antenna.

The conductor 11 should just be comprised with the electrically-conductive material, for example, metal plates, such as Al and Cu, are applicable. Furthermore, the conductor 11 may be a metal layer such as Al or Cu provided on a substrate made of a dielectric material such as glass epoxy.
Similarly, the conductor patch 12 should just be comprised with the electrically-conductive material, for example, metal plates, such as Al and Cu, are applicable. Furthermore, the conductor patch 12 may also be constituted by a metal layer such as Al or Cu provided on a substrate made of a dielectric material such as glass epoxy.
The dipole element 20 is also required to have the element portions 20a and 20b made of a conductive material. For example, a metal plate such as Al or Cu can be applied. Moreover, not only plate shape but metal rods, such as Al and Cu, may be sufficient. Furthermore, the element parts 20a and 20b may also be constituted by a metal layer such as Al or Cu provided on a substrate made of a dielectric material such as glass epoxy.

FIG. 2 is a plan view and a cross-sectional view of the antenna 1 to which the first embodiment is applied. 2A is a plan view of the antenna 1, FIG. 2B is a cross-sectional view of the antenna 1 taken along line IIb-IIb in FIG. 2A, and FIG. 2C is FIG. 2A of the antenna 1. It is sectional drawing in the IIc-IIc line | wire in.
As shown in FIG. 2A, the antenna 1 includes a reflector 10 including a conductor 11 and a plurality of conductor patches 12 and a dipole element 20. For example, the conductor 11 is a square having a side length L1.
As shown in FIG. 2B, the dipole element 20 is provided at a position of a distance L2 as an example of a second distance from the conductor patch 12 of the reflecting plate 10. In the reflecting plate 10, the plurality of conductor patches 12 are provided at a distance L 3 as an example of a first distance from the conductor 11.
As shown in FIGS. 2A and 2C, the plurality of conductor patches 12 of the reflector 10 are configured to have a small surface area in the direction from the upper part to the lower part in the vertical direction.
The distance L4 is from the lower end in the vertical direction of the reflecting plate 10 to the center of the dipole element 20, and the distance L5 is from the upper end in the vertical direction of the reflecting plate 10 to the center of the dipole element 20.
Here, the conductor 11 and the conductor patch 12 in the reflecting plate 10 are not connected. However, the conductor 11 and the conductor patch 12 may be connected by a conductive material to form a so-called mushroom structure.

FIG. 3 is a diagram illustrating a configuration of the plurality of conductor patches 12 and the dipole element 20 in the reflector 10 of the antenna 1 to which the first embodiment is applied. FIG. 3A is a diagram showing the configuration of the plurality of conductor patches 12 of the reflecting plate 10, and FIG. 3B is a diagram showing the configuration of the dipole element 20.
As shown in FIG. 3A, the plurality of conductor patches 12 of the reflector 10 are square conductor patches 12a, 12b, 12c, 12d, and 12e whose side lengths change from the upper part to the lower part in the vertical direction. , 12f, 12g, 12h, 12i.
A plurality of conductor patches 12 having the same side length in the horizontal direction are arranged so as to be symmetric with respect to the center in the horizontal direction.
Conductor patch 12a has one side length L7, conductor patch 12b has one side length L9, conductor patch 12c has one side length L10, conductor patch 12d has one side length L11, conductor patch 12e has one side length L12, conductor patch 12f has one side length L13, conductor patch 12g is one side length L14, the conductor patch 12h is one side length L15, and the conductor patch 12i is one side length L16.
And the conductor patch 12 is arrange | positioned with the space | interval L6 in the horizontal direction, and is arrange | positioned with the space | interval L8 in the vertical direction.

  As shown in FIG. 3B, the dipole element 20 has element portions 20a and 20b arranged in the vertical direction. The horizontal direction of the element parts 20a and 20b is a width L17, and the whole of the element parts 20a and 20b arranged in the vertical direction is a length L19.

Here, an example of numerical values such as the side length L1 in the antenna 1 shown in FIGS. 2 and 3 will be described. The radio wave transmitted and received by the antenna 1 is assumed to have a center wavelength λ ₀ (center frequency f ₀ ) in free space.
In this case, the side length L1 of the conductor 11 of the reflector 10 is 1.3λ ₀ , the distance L2 between the conductor patch 12 and the dipole element 20 in the reflector 10 is 0.02λ ₀ , and the conductor 11 and conductor patch 12 in the reflector 10 L3 is 0.04λ ₀ , the distance L4 from the vertical lower end of the reflector 10 to the center of the dipole element 20 is 0.5λ ₀ , and the distance L5 from the upper end to the center of the dipole element 20 is 0.8λ _0. It is.

Dipole elements 20, the center in the vertical direction of the reflector 10, are arranged offset to 0.15Ramuda ₀ lower. This is because the tilt angle θ can be increased by disposing the center of the dipole element 20 from the center of the conductor 11 to the side where the surface area of the conductor patch 12 is small.
That is, the distance between the end of the conductor patch 12 (the upper end of the conductor patch 12a in FIG. 3A) and the center of the dipole element 20 also affects the tilt angle θ.

Side length L7 is 0.24Ramuda ₀ conductor patches 12a, one side length L9 is 0.21Ramuda ₀ conductor patches 12b, one side length L10 of the conductor patch 12c is 0.18λ _0, one side length L11 of the conductor patch 12d is 0.15λ ₀ , the side length L12 of the conductor patch 12e is 0.13λ ₀ , the side length L13 of the conductor patch 12f is 0.1λ ₀ , the side length L14 of the conductor patch 12g is 0.07λ ₀ , and the side length L15 of the conductor patch 12h is 0 .04λ ₀ , and the side length L16 of the conductor patch 12i is 0.02λ ₀ .
The horizontal interval L6 of the conductor patch 12 is 0.02λ ₀ , and the vertical interval L8 is 0.02λ ₀ . That is, in the first embodiment, the conductor patches 12 in the reflector 10 are arranged at the same interval (interval L6 = interval L8) in the vertical direction and the horizontal direction.

Further, the width L17 of the element portions 20a and 20b of the dipole element 20 is 0.12λ ₀ , and the total length L19 of the element portions 20a and 20b is 0.38λ ₀ .

As described above, in the antenna 1 to which the first embodiment is applied, the height (distance L2 +) from the conductor 11 to the dipole element 20 in the reflector 10 is used by using the reflector 10 that is an EBG structure. distance L3) becomes the 0.06 _0.
In contrast, in the case of only the conductor 11 and the reflection plate 10, the height of generally from conductor 11 to the dipole elements 20 is about 0.25 [lambda _0.
That is, the antenna 1 to which the first embodiment is applied can be lowered in posture as compared with the case where the reflector 10 that is an EBG structure is not used.

Furthermore, when the antenna 1 transmits radio waves, the radiation direction of the main beam can be tilted (tilt angle θ) in the direction in which the area of the conductor patch 12 is large with respect to the normal direction of the reflector 10.
This is because, in the antenna 1 using the reflecting plate 10 constituted by the EBG structure, the conductor 11 and the conductor patch 12 are arranged depending on the surface shape of the conductor patch 12 constituting the reflecting plate 10 and the distance between the conductor patches 12. The inductance and the capacitance between the conductor patches 12 are different. Therefore, the inductance or / and the capacitance is distributed by changing the surface area of the conductor patch 12 from the upper part to the lower part of the reflector 10 in the vertical direction.
Thereby, when the antenna 1 transmits radio waves, the direction of the main beam of the radio waves emitted from the dipole element 20 can be tilted (tilted). In addition, the directivity of the antenna 1 in the vertical direction can also be controlled.
The same applies to the case of receiving radio waves due to the reversibility of the antenna.

The antenna 1 shown in FIGS. 1 and 2 is configured such that a plurality of conductor patches 12 provided in parallel at a predetermined distance from the conductor 11, for example, all of the conductor patches 12 are changed in the vertical direction. .
This can be considered that the ratio of the surface area occupied by the conductor patch 12 per predetermined area so as to include the conductor patch 12 having the largest surface area changes in the vertical direction (predetermined direction). .
The change in the surface area of the conductor patch 12 or the ratio of the surface area occupied by the conductor patch 12 may be set in accordance with the distance in the vertical direction, and the tilt angle and directivity can be controlled by the ratio of these changes.
Further, as shown in FIG. 3, the area of the conductor patch 12 is continuously changed for each piece in the vertical direction, but may be changed for each piece, and may be changed for each different number. It may be changed.

  In the antenna 1 shown in FIGS. 1 and 2, a plurality of conductor patches 12 provided in parallel at a predetermined distance from the conductor 11, for example, in parallel are configured so that the surface area changes in the vertical direction. However, an area including a plurality of conductor patches 12 whose surface area varies in the vertical direction may be defined as an area, and the conductor patch 12 whose surface area does not vary may be provided outside the area. And the dipole element 20 should just be provided in the area | region including the several conductor patch 12 from which a surface area changes in this perpendicular direction.

[Second Embodiment]
In the first embodiment, the dipole element 20 in the antenna 1 includes a pair of element portions 20a and 20b, and transmits and receives vertically polarized waves.
In the second embodiment, in the antenna 1, four dipole elements 21, 22, 23, and 24 are used as another example of the radiating element, and in addition to the vertical polarization, a horizontal polarization orthogonal to the vertical polarization is used. Waves can be sent and received.

FIG. 4 is a perspective view showing an example of the overall configuration of the antenna 1 to which the second embodiment is applied.
The configuration of the reflector 10 is the same as that of the first embodiment. The configuration of the dipole elements 21, 22, 23, 24 will be described later.

FIG. 5 is a plan view and a cross-sectional view of the antenna 1 to which the second embodiment is applied. 5A is a plan view of the antenna 1, FIG. 5B is a cross-sectional view of the antenna 1 taken along line Vb-Vb in FIG. 5A, and FIG. It is sectional drawing in the Vc-Vc line | wire in.
Since it is the same as that of the first embodiment shown in FIG. 2 except that four dipole elements 21, 22, 23, and 24 are used, the same reference numerals are given and description thereof is omitted.
The distance L4 is the distance from the lower end of the reflecting plate 10 in the vertical direction to the center of the dipole element 21 or the dipole element 23. The distance L5 is the upper end of the reflecting plate 10 in the vertical direction of the dipole element 21 or the center of the dipole element 23. The distance is up to.
Here, it is assumed that the dipole elements 21, 22, 23, and 24 and the conductor patch 12 in the reflector 10 are provided at a distance L2. In addition, the distance to the conductor patch 12 in the reflecting plate 10 may be different between the dipole elements 21 and 23 that are vertical polarization elements and the dipole elements 22 and 24 that are horizontal polarization elements. At this time, the distance between the dipole elements 21 and 23 and the conductor patch 12 in the reflector 10 is an example of the second distance, and the distance between the dipole elements 22 and 24 and the conductor patch 12 in the reflector 10 is the third distance. It is an example. The second distance and the third distance may be the same.

FIG. 6 is a diagram illustrating the configuration of the conductor patch 12 and the dipole elements 21, 22, 23, and 24 in the reflector 10 of the antenna 1 to which the second embodiment is applied. 6A is a diagram showing the configuration of the conductor patch 12 in the reflector 10, and FIG. 6B is a diagram showing the configuration of the dipole elements 21, 22, 23, and 24. FIG.
The configuration of the conductor patch 12 of the reflector 10 shown in FIG. 6A is the same as that of the first embodiment shown in FIG. Therefore, the same reference numerals are given and description thereof is omitted.

In FIG. 6B, the four dipole elements 21, 22, 23, and 24 will be described.
The element portions 21a and 21b of the dipole element 21 and the element portions 23a and 23b of the dipole element 23 are arranged in the vertical direction, and the element portions 22a and 22b of the dipole element 22 and the element portions 24a and 24b of the dipole element 24 are arranged in the horizontal direction. Is arranged.
That is, the dipole elements 21 and 23 transmit and receive vertical polarization, and the dipole elements 22 and 24 transmit and receive horizontal polarization. Therefore, the antenna 1 is shared with polarization. Here, the dipole element 21 and the dipole element 23 are referred to as a vertical polarization element, and the dipole element 22 and the dipole element 24 are referred to as a horizontal polarization element.
Note that either one of the dipole elements 21 and 23 and / or one of the dipole elements 22 and 24 may be omitted.

The element portions 21a and 21b of the dipole element 21, the element portions 22a and 22b of the dipole element 22, the element portions 23a and 23b of the dipole element 23, and the element portions 24a and 24b of the dipole element 24 each have a width L17.
The entire dipole elements 21, 22, 23, and 24 have a length L19. The total length L19 is the end of each element part (element part 21a, 21b, element part 22a, 22b, element part 23a, 23b, element part 24a, 24b) of dipole element 21, 22, 23, 24. It is the length from to the end.
Furthermore, the distance between the centers of the dipole element 21 and the dipole element 23 that both transmit and receive vertically polarized waves is a distance L18. Similarly, the distance between the centers of the dipole element 22 and the dipole element 24 that both transmit and receive horizontal polarization is also the distance L18.
Note that the element portions of the dipole elements 21, 22, 23, and 24 are cut obliquely at portions that are close to each other in an L shape, such as the element portion 21a and the element portion 22b.
In the second embodiment, the distance between the centers of the dipole element 21 and the dipole element 23 and the distance between the centers of the dipole element 22 and the dipole element 24 are the same. The distances may be set to different distances depending on (width).

  Each of the dipole elements 21, 22, 23, 24 is also made of a conductive material in each element part (element parts 21a, 21b, element parts 22a, 22b, element parts 23a, 23b, element parts 24a, 24b). For example, a metal plate such as Al or Cu can be applied. The element portions 21a and 21b, the element portions 22a and 22b, the element portions 23a and 23b, and the element portions 24a and 24b may be metal bars such as Al and Cu, for example. Furthermore, the element portions 21a and 21b, the element portions 22a and 22b, the element portions 23a and 23b, and the element portions 24a and 24b are made of metal layers such as Al and Cu provided on a substrate made of a dielectric material such as glass epoxy. It may be constituted by.

Examples of numerical values such as the side length L1 in the antenna 1 shown in FIGS. 5 and 6 are the same as those in the first embodiment. The distance L18 between the centers of the dipole elements 22 and the dipole elements 24 for transmitting and receiving between the centers and both horizontal polarization and dipole elements 21 and the dipole elements 23 which together receive the vertical polarization is 0.42λ _0.

FIG. 7 is a diagram illustrating the directivity in the vertical direction (in the vertical plane) and the frequency (f) dependency of the antenna 1 to which the second embodiment is applied. 7A shows the directivity of the vertical polarization element at f = 0.94f ₀ , FIG. 7B shows the directivity of the vertical polarization element at f = f ₀ , and FIG. 7C shows f = 1. The directivity of the vertical polarization element at 06f ₀ , FIG. 7 (d) shows the directivity of the horizontal polarization element at f = 0.94f ₀ , and FIG. 7 (e) shows the directivity of the horizontal polarization element at f = f ₀ . FIG 7 (f) are diagrams showing the directivity of horizontal polarization element in f = 1.06f _0.
In this directivity, all dipole elements 21, 22, 23, and 24 are fed in the same phase. However, vertical polarization elements (dipole elements 21 and 23 in FIGS. 4 and 5), horizontal polarization elements (Dipole elements 22 and 24 in FIGS. 4 and 5) may be fed with different phases to adjust the radiation direction (beam direction) of radio waves such as tilt angle θ.
These directivities were obtained by simulation.

The tilt angle θ of the vertical polarization element is 6.5 ° at f = 0.94f ₀ (FIG. 7A), 10.5 ° at f = f ₀ (FIG. 7B), f = 1. The angle is 16.8 ° in 06f ₀ (FIG. 7C).
Further, the tilt angle θ of the horizontal polarization element is 15.3 ° at f = 0.94f ₀ (FIG. 7D), 23 ° at f = f ₀ (FIG. 7E), f = 1. It is 21.3 ° in 06f ₀ (FIG. 7 (f)).

As described above, in the antenna 1 to which the second embodiment is applied, the area of the conductor patch 12 is reduced from the upper part to the lower part in the vertical direction. The radiation direction of the beam can be tilted (tilted) from the normal direction of the reflecting plate 10.
The reason why the tilt angle θ varies depending on the frequency f is that the inductance between the conductor 11 and the conductor patch 12 and the capacitance between the conductor patches 12 have frequency dependence.

[Third Embodiment]
In the second embodiment, four dipole elements 21, 22, 23, and 24 are used, and polarization sharing is used so that both vertical polarization and horizontal polarization can be transmitted and received.
However, in the antenna 1 to which the second embodiment is applied, the directivity of the vertical polarization element shown in FIGS. 7A, 7 </ b> B, and 7 </ b> C and FIGS. Comparing the directivity of the horizontal polarization element shown in f), the tilt angle θ of the horizontal polarization element is larger (deeper) than the vertical polarization element for the same frequency f. And the directivity of a horizontal polarization element is compared with the directivity of a vertical polarization element like (alpha) part enclosed with the broken line in FIG.7 (e), and (beta) part enclosed with the broken line in FIG.7 (f). Disturbance is great.
For example, if the directivity of the horizontal polarization element at f = 0.94f ₀ in FIG. 7D is obtained at f = 1.06f ₀ corresponding to FIG. It becomes as shallow as 3 °, which is close to 16.8 ° of the tilt angle θ of the vertical polarization element shown in FIG. And the disturbance of directivity is also reduced.
Therefore, in the third embodiment, the difference in tilt angle θ between the horizontal polarization element and the vertical polarization element and disturbance in the directivity of the horizontal polarization element are suppressed.

  FIG. 8 is a diagram illustrating the relationship between the reflection phase difference of the reflected wave with respect to the incident wave and the distance d between the conductor patches 12 in the reflector 10 formed of the EBG structure. 8A is a diagram for explaining the distance d between the conductor patches 12, FIG. 8B is a diagram for explaining an incident wave and a reflected wave with respect to the reflector 10, and FIG. 8C is a reflection phase difference with respect to the frequency f. It is a figure which shows the relationship between the space | interval d of a conductor patch 12, and.

The relationship between the reflection phase difference with respect to the frequency f and the distance d between the conductor patches 12 shown in FIG. 8C was obtained as follows. First, it is assumed that the conductor patch 12 is placed infinitely at a predetermined distance from the conductor 11 having an infinite area, for example, in parallel with an interval d (see FIG. 8A). Then, a plane wave was used as an incident wave with respect to the reflecting plate 10, and the reflection phase difference of the reflected wave with respect to the incident wave was calculated (see FIG. 8C).
In FIG. 8C, the frequency f at which the reflection phase difference is 0 ° when the interval d is the smallest is shown as the center frequency f ₀ .
Then, when the distance d is the smallest, the reflected phase difference changes from 150 ° in f = 0.5f _0, until -150 ° of f = 1.8f _0.
In addition, in the reflecting plate 10 comprised with the EBG structure, a reflection phase difference is often used in the range of -90 to 90 degrees.

Then, as shown in FIG. 8C, the frequency f at which the reflection phase difference becomes 0 ° increases as the distance d between the conductor patches 12 increases (widens). That is, the graph representing the reflection phase difference shifts to the higher frequency f side.
Therefore, if the interval d between the conductor patches 12 in the reflector 10 is increased (widened) and the frequency f is shifted to the higher side, the horizontal level at f = 0.94f ₀ shown in FIG. the directivity of the polarization element, is considered to be able to be obtained in f = 1.06f _0.

FIG. 9 is a perspective view showing an example of the overall configuration of the antenna 1 to which the third embodiment is applied.
As shown in FIG. 9, in the antenna 1, the horizontal interval L6 of the conductor patch 12 in the reflector 10 of the antenna 1 to which the second embodiment shown in FIG. A wide interval L6 ′ is set. The vertical interval L8 between the conductor patches 12 is the same as that of the antenna 1 to which the second embodiment shown in FIG. 6A is applied.

FIG. 10 is a plan view of the antenna 1 to which the third embodiment is applied.
Note that the side length L1 of the conductor 11 in the reflector 10 is the same as that of the second embodiment shown in FIG.
As shown in FIG. 10, the conductor patches 12 in the reflector 10 are arranged at an interval L6 ′ whose horizontal direction is wider than the interval L6 to which the second embodiment shown in FIG. 5A is applied. Compared with the case of the second embodiment shown in FIG. 5A, the conductor patch 12 is disposed so as to spread in the horizontal direction.
Since other configurations are the same as those of the second embodiment, the same reference numerals are given and description thereof is omitted.

FIG. 11 is a diagram showing the directivity in the vertical direction (in the vertical plane) of the antenna 1 to which the third embodiment is applied and its frequency (f) dependency. 11A shows the directivity of the vertical polarization element at f = 0.94f ₀ , FIG. 11B shows the directivity of the vertical polarization element at f = f ₀ , and FIG. 11C shows f = 1. Directivity of the vertical polarization element at 06f ₀ , FIG. 11D shows the directivity of the horizontal polarization element at f = 0.94f ₀ , and FIG. 11E shows the directivity of the horizontal polarization element at f = f ₀ . FIG 11 (f) are diagrams showing the directivity of horizontal polarization element in f = 1.06f _0.
These directivity, as the interval L6 '= 2 × distance L6 = 0.04 _0, obtained by simulation.

The tilt angle θ of the vertical polarization element is 6.3 ° at f = 0.94f ₀ (FIG. 11A), 10 ° at f = f ₀ (FIG. 11B), and f = 1.06f _0. In FIG. 11C, it is 15.5 °. The tilt angle θ of these vertical polarization elements is close to the tilt angle θ of the vertical polarization element of the antenna 1 to which the second embodiment shown in FIGS. 7A, 7B, and 7C is applied. .
On the other hand, the tilt angle θ of the horizontal polarization element is 7.5 ° at f = 0.94f ₀ (FIG. 11 (d)), 10.3 ° at f = f ₀ (FIG. 11 (e)), f = It is 13.8 degrees in 1.06f ₀ (FIG. 11 (f)). The tilt angle θ of these horizontal polarization elements is smaller than the tilt angle θ of the horizontal polarization element of the antenna 1 to which the second embodiment shown in FIGS. 7D, 7E, and 7F is applied. (Shallow) and less disturbed directivity.

  As described above, in the antenna 1 to which the third embodiment is applied, the area of the conductor patch 12 is reduced from the upper part to the lower part in the vertical direction, and the horizontal direction of the conductor patch 12 is set to the interval L6 ′. The interval is larger than the interval L6 to which the second embodiment is applied. Thereby, the radiation direction of the main beam of the vertical polarization element and the horizontal polarization element can be tilted (tilted) from the normal direction of the reflecting plate 10, and the vertical polarization element and the horizontal polarization element at the same frequency f The difference in the tilt angle θ is suppressed. In addition, the disturbance of directivity of the horizontal polarization element can be suppressed.

In the third embodiment, the horizontal direction of the conductor patch 12 in the reflecting plate 10 is set to an interval L6 ′ wider than the interval L6 from the interval L6 to which the second embodiment is applied. Same as L8. Thus, the directivity of the horizontal polarization element is changed while maintaining the directivity of the vertical polarization element in the same manner as the antenna 1 of the second embodiment.
That is, by setting the horizontal interval L6 and the vertical interval L8 separately, the directivity of the horizontal polarization element and the vertical polarization element can be controlled separately.

Next, it will be described that the centers of the dipole elements 21 and 23 are shifted from the center of the reflection plate 10 (reflection plate center) in the vertical direction. The positions of the dipole elements 22 and 24 are also shifted with the dipole elements 21 and 23. Accordingly, the dipole elements 21, 22, 23, and 24 are collectively referred to as a dipole element, and the center of the dipole elements 21 and 23 is referred to as a dipole element center.
FIG. 12 is a diagram illustrating that the center of the dipole element is shifted from the center of the reflector in the vertical direction. 12A shows a case where the center of the dipole element is shifted from the center of the reflector to the positive side in the vertical direction, that is, the side where the surface area of the conductor patch 12 is large. FIG. When the center is arranged, FIG. 12C shows a case where the center of the dipole element is shifted from the center of the reflector to the negative side in the vertical direction, that is, the side where the surface area of the conductor patch 12 is small.
When the position of the dipole element center (center of the dipole element 20) with respect to the reflector center (center of the reflector 10) is a position R, the position R is 0.4λ ₀ in FIG. 12A and FIG. ) Is ₀ , and in FIG. 12C is -0.4λ0.

FIG. 13 is a diagram showing the relationship between the position R of the dipole element center relative to the center of the reflector and the tilt angle θ.
The tilt angle θ of the vertical polarization element and the horizontal polarization element changes with the position R. When the position R is negative, the tilt angle θ is positive, that is, the main beam is inclined to the positive side in the vertical direction (the side where the surface area of the conductor patch 12 is large). On the other hand, when the position R is positive, the tilt angle θ is negative, that is, the main beam is tilted to the negative side in the vertical direction (side where the surface area of the conductor patch 12 is small).
However, as shown in FIG. 13, when the position R is negative, the difference between the tilt angle θ of the vertical polarization element and the tilt angle θ of the horizontal polarization element is larger than that when the position R is positive. Small. Therefore, it is preferable that the dipole element is shifted from the side where the position R is negative, that is, the side where the surface area of the conductor patch 12 is small.

[Fourth Embodiment]
In the fourth embodiment, in the antenna 1, the conductor patch 12 is not provided in a portion where the dipole elements 21, 22, 23, and 24 are opposed to each other among the plurality of conductor patches 12 of the reflector 10. This makes it easy to provide a power feeding circuit that feeds power to the dipole elements 21, 22, 23, and 24.

FIG. 14 is a plan view of the antenna 1 to which the fourth embodiment is applied.
As shown in FIG. 14, in the antenna 1, in the plurality of conductor patches 12 of the antenna 1 to which the third embodiment shown in FIG. 10 is applied, of the plurality of conductor patches 12c arranged in the horizontal direction, One provided in the center of the direction is not provided. Similarly, of the plurality of conductor patches 12d arranged in the horizontal direction, three provided at the center in the horizontal direction are not provided. Further, among the plurality of conductor patches 12e arranged in the horizontal direction, three provided at the center in the horizontal direction are not provided.
Other configurations are the same as those of the antenna 1 to which the third embodiment is applied.

FIG. 15 is a diagram illustrating the directivity in the vertical direction (in the vertical plane) of the antenna 1 to which the fourth embodiment is applied. FIG. 15A shows the directivity of the vertical polarization element at f = f ₀ , and FIG. 15B shows the directivity of the horizontal polarization element at f = f ₀ .
As shown in FIG. 15A, the tilt angle θ of the vertical polarization element is 9.3 ° at f = f ₀ , and as shown in FIG. 15B, the tilt angle θ of the horizontal polarization element is f = It is 12.8 ° at f ₀ .
As described above, the radiation direction of the main beam of the vertical polarization element and the horizontal polarization element is tilted from the normal direction of the reflection plate 10 without providing the conductor patch 12 in the portion where the dipole elements 21, 22, 23, 24 are provided. (Tilt).

[Fifth Embodiment]
In the first to fourth embodiments, in the antenna 1, the plurality of conductor patches 12 of the reflector 10 have a square surface shape. In the fifth embodiment, in the antenna 1, the surface shape of the plurality of conductor patches 12 of the reflector 10 is rectangular.

FIG. 16 is a plan view of the antenna 1 to which the fifth embodiment is applied.
As shown in FIG. 16, in the antenna 1, the surface shape of the conductor patch 12 of the antenna 1 to which the third embodiment shown in FIG. 10 is applied is changed from a square to a rectangle.
Other configurations are the same as those of the antenna 1 to which the third embodiment is applied.

FIG. 17 is a diagram showing the directivity in the vertical direction (in the vertical plane) of the antenna 1 to which the fifth embodiment is applied. FIG. 17A shows the directivity of the vertical polarization element at f = f ₀ , and FIG. 17B shows the directivity of the horizontal polarization element at f = f ₀ .
As shown in FIG. 17A, the tilt angle θ of the vertical polarization element is 11.5 ° at f = f ₀ . However, as shown in FIG. 17B, the directivity at f = f ₀ is disturbed in the horizontal polarization element. As described in the third embodiment, by further increasing the horizontal distance L6 ′, the disturbance of directivity of the horizontal polarization element is suppressed, and the tilt angle θ is the same as that of the vertical polarization element. Can be set to a value.
Thus, even if the surface shape of the conductor patch 12 is rectangular, the radiation direction of the main beam of the vertical polarization element and the horizontal polarization element can be tilted (tilted) from the normal direction of the reflector 10.
In the antenna 1 shown in FIG. 16, the conductor patch 12 is a rectangle whose horizontal direction is longer than the vertical direction, but may be a rectangle whose horizontal direction is shorter than the vertical direction.

[Sixth Embodiment]
In the fifth embodiment, in the antenna 1, the surface shape of the plurality of conductor patches 12 of the reflector 10 is circular.

FIG. 18 is a plan view of the antenna 1 to which the sixth embodiment is applied.
In the antenna 1 to which the sixth embodiment is applied, the surface shape of the conductor patch 12 of the antenna 1 to which the third embodiment shown in FIG. 10 is applied is changed from a square to a circle.
Other configurations are the same as those of the antenna 1 to which the third embodiment is applied.

FIG. 19 is a diagram showing the directivity in the vertical direction (in the vertical plane) of the antenna 1 to which the sixth embodiment is applied. FIG. 19A shows the directivity of the vertical polarization element at f = f ₀ , and FIG. 19B shows the directivity of the horizontal polarization element at f = f ₀ .
As shown in FIG. 19A, the tilt angle θ of the vertical polarization element is 6 ° at f = f ₀ , and as shown in FIG. 19B, the tilt angle θ of the horizontal polarization element is f = f _0. At 8 °.
Thus, even if the surface shape of the conductor patch 12 is circular, the radiation direction of the main beam of the vertical polarization element and the horizontal polarization element can be tilted (tilted) from the normal direction of the reflector 10.
The surface shape of the conductor patch 12 may be an ellipse.

[Seventh Embodiment]
In the seventh embodiment, in the antenna 1, the surface shape of the plurality of conductor patches 12 of the reflecting plate 10 is a square having the same surface area, and the vertical interval is changed.

FIG. 20 is a plan view of the antenna 1 to which the seventh embodiment is applied.
In the antenna 1 to which the seventh embodiment is applied, the surface shape of the conductor patch 12 is a square having the same surface area. Then, the conductor patch 12 is arranged with intervals L81, L82, L83, L84, L85, L86 from the lower part to the upper part in the vertical direction and gradually narrowed (L81>L82>L83>L84>L85> L86). ).
Other configurations are the same as those of the antenna 1 to which the third embodiment is applied.

FIG. 21 is a diagram illustrating the directivity in the vertical direction (in the vertical plane) of the antenna 1 to which the seventh embodiment is applied. FIG. 21A shows the directivity of the vertical polarization element at f = f ₀ , and FIG. 21B shows the directivity of the horizontal polarization element at f = f ₀ .
As shown in FIG. 21A, the tilt angle θ of the vertical polarization element is 5.3 ° at f = f ₀ , and as shown in FIG. 21B, the tilt angle θ of the horizontal polarization element is f = It is 14.3 ° at f ₀ .
As described above, even if the conductor patches 12 have the same surface area and are arranged with different vertical intervals, the radiation directions of the main beams of the vertical polarization element and the horizontal polarization element are inclined from the normal direction of the reflector 10. (Tilt).

[Eighth Embodiment]
In the first embodiment, the dipole element 20 is used in the antenna 1, and the dipole elements 21, 22, 23, and 24 are used in the antenna 1 in the second to seventh embodiments. In the eighth embodiment, the antenna 1 uses a patch element which is still another example of a radiating element, and is combined with the reflector 10 to form a patch antenna.

FIG. 22 is a perspective view showing an example of the overall configuration of the antenna 1 to which the eighth embodiment is applied.
In the antenna 1 to which the eighth embodiment is applied, the dipole element 20 of the antenna 1 to which the first embodiment shown in FIG. The patch element 25 includes a patch portion 25a and a power feeding portion 25b. Power is supplied from the back side of the reflector 10 to the power supply unit 25b.
Other configurations are the same as those of the antenna 1 to which the first exemplary embodiment is applied, and thus the same reference numerals are given and description thereof is omitted.

[Ninth Embodiment]
In the first to eighth embodiments, the surface area of the conductor patch 12 in the reflector 10 is changed in the vertical direction.
In the ninth embodiment, the surface area of the conductor patch 12 in the reflecting plate 10 changes not only in the vertical direction but also in the horizontal direction.

FIG. 23 is a perspective view showing an example of the overall configuration of the antenna 1 to which the ninth embodiment is applied. Here, as shown in FIG. 23, the direction along one side of the reflecting plate 10 (downward direction on the paper surface) is the x direction (vertical direction), and the direction orthogonal to one side (direction toward the right side on the paper surface). Is the y direction (horizontal direction). The direction perpendicular to the reflecting plate 10 is taken as the z direction. A direction between the x direction and the y direction is defined as a _{φ45 °} direction.
As shown in FIG. 23, in the reflector 10 of the antenna 1, the conductor patch 12 is arranged so that the surface area becomes smaller as it goes in the x direction, and the surface area becomes smaller as it goes in the y direction. A conductor patch 12 is disposed. That is, the conductor patch 12 having a small surface area is arranged in two directions, the x direction and the y direction.
Other configurations such as the dipole elements 21, 22, 23, and 24 are the same as those in the second embodiment, and thus the same reference numerals are given and description thereof is omitted.

FIG. 24 is a plan view of the antenna 1 to which the ninth embodiment is applied.
As shown in FIG. 24, the conductor patch 12 in the reflecting plate 10 is provided with a conductor patch 12 having a small surface area along the x direction and the y direction. The spacing between the conductor patches 12 is also increased along the x direction and the y direction.
Since other configurations are the same as those of the second embodiment, the same reference numerals are given and description thereof is omitted.

FIG. 25 is a diagram illustrating the directivity of the vertical polarization element of the antenna 1 to which the ninth embodiment is applied. 25 (a) shows the directivity of the vertical polarization element in the xz plane, FIG. 25 (b) shows the directivity of the vertical polarization element in the yz plane, and FIG. 25 (c) shows φ _This is the directivity of the vertical polarization element in the _{45 °} -z plane.
As shown in FIG. 25A, the tilt angle θ of the vertical polarization element of the antenna 1 is 10.3 ° in the −x direction, that is, the direction in which the surface area of the conductor patch 12 increases. Further, as shown in FIG. 25B, the tilt angle θ of the vertical polarization element of the antenna 1 is 5.8 ° in the −y direction, that is, the direction in which the surface area of the conductor patch 12 increases. As shown in (c), the tilt angle θ of the vertical polarization element of the antenna 1 is 10.3 ° in the −φ _{45 °} direction.

  As described above, the surface area of the conductor patch 12, that is, the ratio of the surface area occupied by the conductor patch 12 per predetermined area so as to include the conductor patch 12 having the largest surface area is changed in a plurality of directions in advance. The tilt angle θ and directivity of the main beam can be set in a predetermined direction.

  Instead of the dipole elements 21, 22, 23, 24, the patch element 25 described in the eighth embodiment may be used.

  As described above, in the antenna 1 using the reflector 10 made of the EBG structure, the distance between the conductor 11 and the conductor patch 12 depends on the surface shape of the conductor patch 12 constituting the reflector 10 and the distance between the conductor patches 12. The inductance and the capacitance between the conductor patches 12 change. Therefore, the reflector 10 has a distribution of inductance and / or capacitance, so that the reflector 10 for the main beam of radio waves transmitted and received by the radiating elements (dipole elements 20, 21, 22, 23, 24, patch element 25) is transmitted. It is possible to control the tilt angle θ and the directivity with respect to the normal direction. Note that the tilt angle θ and directivity can be set by the surface shape, area, interval, etc. of the conductor patch 12.

  In the first to fourth embodiments and the seventh to ninth embodiments, the surface shape of the conductor patch 12 is square, and in the fifth embodiment, the conductor patch 12 is used. The surface shape of was made rectangular. Furthermore, in the sixth embodiment, the surface shape of the conductor patch 12 is circular. The surface shape of the conductor patch 12 may be a polygon or a shape surrounded by a curve. Furthermore, the shape enclosed by the straight line and the curve may be sufficient.

  In the second to seventh embodiments and the ninth embodiment, the radio wave can be transmitted and received in the vertical polarization and the horizontal polarization. For example, when the radio wave has a polarization of ± 45 °, the radiating element (dipole elements 20, 21, 22, 23, 24) may be rotated by 45 ° around the center thereof.

  Further, in order to widen the band of radio waves that can be transmitted and received, a parasitic element around the radiation element (dipole elements 20, 21, 22, 23, 24, patch element 25) in the antenna 1 and / or far from the conductor 11 is provided. May be provided.

DESCRIPTION OF SYMBOLS 1 ... Antenna, 10 ... Reflecting plate, 11 ... Conductor, 12, 12a, 12b, 12c, 12d, 12e, 12f, 12g, 12h, 12i ... Conductor patch, 20, 21, 22, 23, 24 ... Dipole element, 25 ... Patch element, θ ... Tilt angle, λ ₀ ... Center wavelength, f ₀ ... Center frequency

Claims (7)

A conductor made of a conductive material;
A ratio of a surface area that is made of a conductive material and is disposed at a predetermined first distance in a direction orthogonal to the plane including the conductor and that faces the conductor per predetermined area is determined in advance. A plurality of conductor patches having regions that vary in direction;
In a direction perpendicular to the plane containing the conductor, provided in the second predetermined distance from said plurality of conductor patches, a radiating element for transmitting and receiving radio waves through the feed point has a feeding point, a Prepared ,
The antenna is characterized in that the radiating element has directivity for transmission / reception of radio waves in a direction inclined to a side where the ratio of the surface area of the plurality of conductor patches is large . Transmission / reception of the radiating element is provided at a predetermined third distance from the plurality of conductor patches in a direction orthogonal to the plane including the conductor and has another feeding point through the other feeding point. further comprising another radiating element for transmitting and receiving radio waves polarization intersecting the polarization of the radio wave,
2. The antenna according to claim 1, wherein the other radiating element has directivity for transmission / reception of radio waves in a direction inclined to a side where the ratio of the surface area of the plurality of conductor patches is large .   The antenna according to claim 1, wherein the change in the ratio of the surface area facing the conductor in the region of the plurality of conductor patches is a change in the surface area of the conductor patch included in the region.   The antenna according to claim 3, wherein an interval between the plurality of conductor patches is different between the predetermined direction and a direction orthogonal to the predetermined direction.   3. The antenna according to claim 1, wherein the change in the ratio of the surface area facing the conductor in the region of the plurality of conductor patches is a change in the distance between the conductor patches included in the region. .   The center of one or both of the radiating element and the other radiating element is arranged so as to be shifted from the center of the region of the plurality of conductor patches in the predetermined direction. Item 3. The antenna according to Item 2.   The antenna according to claim 2, wherein the plurality of conductor patches are provided so as to exclude a portion facing one or both of the radiating element and the other radiating element.

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