JP7016554B2 - Antennas, array antennas, sector antennas and dipole antennas - Google Patents

Description

The present invention relates to antennas, array antennas, sector antennas and dipole antennas.

For the base station antenna of mobile communication, a plurality of sector antennas that radiate radio waves for each sector set corresponding to the direction in which radio waves are radiated are used in combination. As the sector antenna, an array antenna in which radiating elements such as a dipole antenna are arranged in an array is used.

Patent Document 1 describes a polarization-shared Yagi antenna that shares the first and second polarizations that are orthogonal to each other using a waveguide, a radiator, and a reflector arranged along the central axis. Is a pair of first dipole antenna elements that face each other along the plane of polarization of the first polarization and at predetermined intervals about the central axis, and along the plane of polarization of the second polarization and at the center. A pair of second dipole antenna elements facing each other at predetermined intervals about an axis and a polarization-shared Yagi antenna including the two dipole antenna elements are described.

In Patent Document 2, the first, second, third, and fourth 2 are arranged so that the respective longitudinal center points are in contact with each other at 0 °, 90 °, 180 °, and 270 ° positions of the circumference of a predetermined diameter. Described is a polarization shared antenna device including a linear folded antenna element and first to fourth balanced two lines whose tips are connected to feeding points of the antenna element, respectively.

Japanese Unexamined Patent Publication No. 2016-046626 Japanese Unexamined Patent Publication No. 2016-119551

By the way, as a sector antenna, an antenna having a common polarization may be used for the purpose of improving communication quality / increasing communication capacity. In addition to miniaturization, wideband antennas are required for such antennas that share polarization.
An object of the present invention is to provide a small antenna having a wide band and sharing a polarization.

For this purpose, the antenna to which the present invention is applied is connected to a reflecting member having a flat surface portion, a pair of radiating portions, one side connected to opposite portions of the pair of radiating portions, and the other side connected to the reflecting member. A first dipole antenna having a balun portion, provided on a flat surface portion of a reflection member, and transmitting and receiving radio waves of the first polarization by a pair of radiation portions, a pair of radiation portions, and a pair of radiation portions on one side. It has a balun portion connected to the opposite portion of the antenna and the other side is connected to the reflective member, and is provided on the flat surface portion of the reflective member. The first dipole antenna and the second dipole antenna are provided with a second dipole antenna for transmitting and receiving The bent portion has a bent portion on the opposite side of the above, and the bent portion is capacitively coupled to the first dipole antenna and the second dipole antenna by facing the planar coupling portion of the bent portion. It includes a surface-shaped first bent portion and a second bent portion that bends diagonally toward the balun portion with respect to the reflective member .

Further, it can be characterized by including two non-feeding elements arranged close to each of the first dipole antenna and the second dipole antenna.
By doing so, the frequency band can be widened.

In such an antenna, a pair of radiating portions and a balun portion having one side connected to the opposite portions of the pair of radiating portions and the other side connected to the reflecting member are provided on the flat surface portion of the reflecting member and paired. A third dipole antenna that transmits and receives radio waves of the first polarization by the radiating part of the above, a pair of radiating parts, and a balun part in which one side is connected to the opposite portion of the pair of radiating parts and the other side is connected to the reflecting member. A fourth dipole antenna, which is provided on a flat surface of a reflective member and transmits and receives radio waves of a second polarization by a pair of radiation portions, is further provided, and a first dipole antenna and a second dipole are provided. The antenna, the third dipole antenna, and the fourth dipole antenna have a bent portion in which the opposite side of each pair of radiating portions is bent to the flat portion side or the opposite side of the flat portion side of the reflecting member. However, the bent portion includes a planar first bent portion that is capacitively coupled to each other by facing each other , and a second bent portion that bends diagonally toward the balun portion with respect to the reflective member. It can be characterized by that.

Further, the first dipole antenna, the second dipole antenna, the third dipole antenna and the fourth dipole antenna are provided at the corners of the virtually provided square, and the first dipole antenna and the second dipole antenna are provided. Each of the radiating portions of the dipole antenna, the third dipole antenna, and the fourth dipole antenna has an extension portion having a portion parallel to the diagonal line of the square and a portion bent and extended along the side from the end portion of the portion. Can be characterized by being provided with.
By doing so, the planar shape of the antenna can be reduced.

The radiation portions of the first dipole antenna, the second dipole antenna, the third dipole antenna, and the fourth dipole antenna are characterized in that they transmit and receive radio waves polarized along the diagonal direction of the square. can do.
By doing so, the directivity of the polarization shared antenna can be strengthened.

Further, on the side surrounded by the first dipole antenna, the second dipole antenna, the third dipole antenna and the fourth dipole antenna, the first dipole antenna, the second dipole antenna, the third dipole antenna and the second dipole antenna are located. It can be characterized by including four non-feeding elements arranged in close proximity to each of the four dipole antennas.
By doing so, the frequency band can be widened.

Furthermore, the first dipole antenna, the second dipole antenna, the third dipole antenna and the fourth dipole antenna are provided at the corners of the virtually provided square, and the first dipole antenna and the second dipole antenna are provided. The balun portions of the dipole antenna, the third dipole antenna, and the fourth dipole antenna are connected to the reflective member on the other side, and the other side is the first dipole antenna, the second dipole antenna, the third dipole antenna, and the fourth dipole antenna. It can be characterized in that it is provided at an angle to the outside of the side surrounded by the dipole antenna.
By doing so, the antenna can be in a low position.

From another point of view, the array antenna to which the present invention is applied is connected to a reflecting member having a flat surface portion, a pair of radiating portions, and one side connected to opposite portions of the pair of radiating portions, and the other side is a reflecting member. A first dipole antenna and a third dipole antenna that transmit and receive radio waves of the first polarization in the first frequency band by a pair of radiating parts and a pair of radiating parts. A second dipole antenna and a fourth dipole antenna that transmit and receive radio waves of a second polarization different from the first polarization of the first frequency band are provided respectively, and are arranged in a row on the flat surface portion of the reflecting member. Along with the arrangement of the plurality of first antennas and the plurality of first antennas, the radio waves in the second frequency band higher than the first frequency band are arranged with respect to the plane portion of the reflecting member, respectively. The first dipole antenna, the second dipole antenna, the third dipole antenna, and the fourth dipole antenna are provided on the opposite side of each pair of radiating parts. The opposite side has a bent portion bent on the flat surface side or the opposite side of the flat surface portion side of the reflective member, and the planar joint portions of the bent portion face each other so that they are capacitively coupled to each other.
By doing so, frequency sharing is possible.

In such an array antenna, the arrangement of the plurality of second antennas can be characterized in that the arrangement of the plurality of second antennas is arranged so as to overlap with the arrangement of the plurality of first antennas with respect to the plane portion of the reflecting member.
By doing so, the array antenna of the frequency sharing antenna can be miniaturized.

Further, the spacing between the arrangements of the plurality of first antennas can be three times the spacing between the arrangements of the plurality of second antennas.
The two second antennas are arranged in the area surrounded by the first dipole antenna, the second dipole antenna, the third dipole antenna, and the fourth dipole antenna in the first antenna. Can be characterized.
By doing so, it becomes easy to configure the frequency sharing antenna.

Further, from another point of view, the sector antenna to which the present invention is applied is connected to a reflective member having a flat surface portion, a pair of radiating portions and one side of the pair of radiating portions facing each other, and the other side is a reflecting member. A first dipole antenna having a balun part to be connected and transmitting and receiving radio waves of the first polarization by a pair of radiation parts, and a second polarization different from the first polarization by a pair of radiation parts. A plurality of antennas each including a second dipole antenna for transmitting and receiving radio waves include an array antenna provided on a flat surface of a reflecting member and a cover covering the array antenna, and the first dipole antenna and the first. The dipole antenna of 2 has a bent portion in which the opposite side of each pair of radiating portions on the opposite side is bent to the flat surface side or the side opposite to the flat surface portion side of the reflecting member, and the bent portion has a bent portion. A planar first bent portion in which the first dipole antenna and the second dipole antenna face each other to be capacitively coupled , and a second bent portion that bends diagonally toward the balun portion with respect to the reflective member. Including .

Furthermore, from another point of view, the dipole antenna to which the present invention is applied has a pair of radiating portions and a balun portion in which one side is connected to the opposite portion of the pair of radiating portions and the other side is connected to the reflecting member. , The opposite side of the pair of radiating portions to the opposite side has a bent portion bent to the reflective member side or the opposite side to the reflective member side, and the bent portion is provided adjacent to another radiating portion. Includes a planar first bent portion that is capacitively coupled by facing each other, and a second bent portion that bends diagonally toward the balun portion with respect to the reflective member .

In such a dipole antenna, each of the pair of radiating portions includes a stretched portion having a portion extending from the opposite portion to the opposite side and a portion bending and extending from the end portion of the portion, and each of the pair of radiating portions is bent and extended. The bending direction of the portions can be characterized by being on the same side in the pair of radiating portions.
By doing so, the dipole antenna can be miniaturized.

Further, each of the pair of radiation portions may be characterized by having an edge portion provided so as to extend from one edge of the stretched portion to the reflective member.
By doing so, the capacitive coupling can be increased.

The balun portion can be characterized by including a portion in which the stretched portion is inclined in a direction opposite to the bending direction.
By doing so, the attitude of the dipole antenna can be lowered.

According to the present invention, it is possible to provide a small antenna having a wide band and sharing polarization.

It is a figure which shows an example of the whole structure of the base station antenna of the mobile communication to which this embodiment is applied. (A) is a perspective view of the base station antenna, and (b) is a diagram illustrating an installation example of the base station antenna. It is a figure which shows an example of the structure of the array antenna in this embodiment. (A) is a perspective view, and (b) is a plan view (xy plane). It is a figure explaining the antenna module. (A) is a perspective view, (b) is a plan view, and (c) is a side view. It is a figure explaining an antenna. (A) is a perspective view, (b) is a plan view, and (c) is a side view. Examples and Comparative Examples are for explaining the effect of capacitive coupling. (A) is an embodiment consisting of four antenna modules, and (b) is a comparative example consisting of one antenna module. It is a figure which shows the evaluation result of the return loss in the Example and the comparative example shown in FIG. It is a figure explaining the deformation example of the shape of the bent part of the radiating part and the bent part of a radiating part facing each other. (A) is the present embodiment, (b) is the modified example 1, (c) is the modified example 2, and (d) is the modified example 3.

The sector antenna used for the base station antenna may be shared in polarization and may be shared in frequencies used in a plurality of frequency bands. As an example, it is required to shift the frequency band on the low frequency band side, which was 698 MHz to 960 MHz, to the low frequency side, such as 617 MHz to 894 MHz, and widen the band. When the frequency is lowered, the shape of an antenna element such as a dipole antenna inevitably becomes large. However, as a sector antenna, it is required not to make it large, that is, a small antenna.
Hereinafter, embodiments of the present invention (the present embodiments) will be described in detail with reference to the accompanying drawings. In the following, the sector antenna with shared frequency will be described, but the sector antenna with shared frequency does not have to be used.

<Base station antenna>
FIG. 1 is a diagram showing an example of an overall configuration of a base station antenna for mobile communication to which the present embodiment is applied. FIG. 1A is a perspective view of a base station antenna, and FIG. 1B is a diagram illustrating an installation example of a base station antenna.
As shown in FIG. 1A, the base station antenna is, for example, a plurality of sector antennas 1-1 to 1-3 held in a steel tower 2 provided perpendicular to the ground surface (sector antennas if not distinguished). 1) is provided. Each of the sector antennas 1-1 to 1-3 includes an array antenna 3. The array antenna 3 is covered with a radome 4 which is a cover for protecting the array antenna 3 from wind and rain. That is, the outside of the sector antennas 1-1 to 1-3 is the radome 4, and the array antenna 3 is housed inside the radome 4. In FIG. 1A, the radome 4 has a cylindrical shape, but may have another shape. The base station antenna transmits / receives radio waves in the cell 5 shown in FIG. 1 (b).

As will be described later, the sector antenna 1 exemplified here is a polarization-shared and frequency-shared antenna that transmits and receives radio waves having orthogonal polarizations in each of two different frequency bands. Here, two different frequency bands are referred to as a high frequency band and a low frequency band. The frequency designed in the high frequency band is defined as the frequency f _0H (wavelength λ _0H ), and the frequency designed in the low frequency band is defined as the frequency f _0L (wavelength λ _0L ). The wavelengths λ _0H and λ _{0 L} are free space wavelengths. For example, the high frequency band is 2 GHz band, and the low frequency band is 617 MHz to 894 MHz as described above. Here, the frequency band from 617 MHz to 894 MHz is referred to as a 700 MHz band.
The low frequency band is an example of the first frequency band, and the high frequency band is an example of the second frequency band.

Here, as shown in FIG. 1A, xyz coordinates are set for the array antenna 3 included in the sector antenna 1-1. That is, the vertical direction of the array antenna 3, as shown in FIG. 2 described later, y Set in the direction. Then, the x direction is provided along the lateral direction of the flat surface portion 410 of the reflective plate 400 in the array antenna 3, and the z direction is set in the direction perpendicular to the flat surface portion 410 of the reflective plate 400.
The x-direction, y-direction, and z-direction are orthogonal to each other. Then, the x direction is the horizontal direction with respect to the ground surface, the y direction is the vertical direction with respect to the ground surface, the yz plane is the vertical plane, and the xz plane is the horizontal plane.

As shown in FIG. 1 (b), the base station antenna transmits / receives radio waves in the cell 5. The cell 5 is divided into a plurality of sectors 6-1 to 6-3 (indicated as sector 6 when not distinguished) corresponding to the sector antennas 1-1 to 1-3. The sector antennas 1-1 to 1-3 are set so that the direction of the main lobe 7 of the radio waves transmitted and received by each of the array antennas 3 faces the corresponding sectors 6-1 to 6-3.

In addition, in FIG. 1, it is assumed that the base station antenna includes three sector antennas 1-1 to 1-3 and sectors 6-1 to 6-3 corresponding to these. However, the sector antenna 1 and the sector 6 may be a predetermined number other than 3. Further, in FIG. 1B, the sector 6 is configured by dividing the cell 5 into three equal parts (central angle 120 °), but it does not have to be evenly divided, and any one sector 6 is the other. It may be configured wider or narrower than the sector 6 of.

As shown in FIG. 1, each sector antenna 1 is connected to transmission / reception cables 8-1 to 8-4 for transmitting a transmission signal and a reception signal to the array antenna 3. The transmission / reception cables 8-1 and 8-2 transmit transmission signals and reception signals of radio waves having polarized waves orthogonal to each other in the high frequency band. The transmission / reception cables 8-3 and 8-4 transmit transmission signals and reception signals of radio waves having orthogonal polarizations in the low frequency band.
The transmission / reception cables 8-1 to 8-4 are connected to a transmission / reception unit (not shown) provided in the base station (not shown) for generating a transmission signal and receiving the reception signal. The transmission / reception cables 8-1 to 8-4 are, for example, coaxial cables.
The base station antenna, the sector antenna 1, the array antenna 3, and the like can transmit and receive radio waves due to the reversibility of the antennas.

The sector antenna 1 distributes / synthesizes transmission / reception signals to a plurality of antennas (antennas 10-1 to 10-3 and 20-1 to 20-10 shown in FIG. 2 to be described later) included in the array antenna 3. A circuit and a phase shifter for different phases of transmitted / received signals between a plurality of antennas (between antennas 10-1 to 10-3 shown in FIG. 2 and / and between antennas 20-1 to 20-10) are provided. You may. By making the phases of the transmitted / received signals different between the antennas, the radiation angle of the radio wave (beam) can be tilted (tilted) toward the ground.

<Array antenna 3>
FIG. 2 is a diagram showing an example of the configuration of the array antenna 3 in the present embodiment. 2 (a) is a perspective view, and FIG. 2 (b) is a plan view (xy plane). Here, the array antenna 3 provided with the sector antenna 1-1 shown in FIG. 1A is taken as an example.
As shown in FIGS. 2 (a) and 2 (b), the array antenna 3 is a antenna 10-1 to 10-3 (when not distinguished from the antenna 10) that transmits and receives radio waves having polarizations orthogonal to each other in the low frequency band. (Notation) and antennas 20-1 to 20-10 (indicated as antenna 20 when not distinguished) for transmitting and receiving radio waves having polarized waves orthogonal to each other in the high frequency band are provided. The antenna 10 and the antenna 20 include a common reflector 400. Here, the antenna 10 is an example of the first antenna, the antenna 20 is an example of the second antenna, and the reflector 400 is an example of the reflecting member.

The reflector 400 includes a flat surface portion 410 and two rising portions 420. The rising portion 420 is provided so as to rise vertically (+ z direction) from both ends of the flat surface portion 410 in the x direction to the flat surface portion 410.
Antennas 10-1 to 10-3 and 20-1 to 20-10 are arranged in a row in the y direction on the surface of the flat surface portion 410 of the reflector 400 on the + z side.

The reflector 400 is made of a conductive member. The reflector 400 is made of, for example, a metal plate such as aluminum, copper, or stainless steel. The rising portion 420 is manufactured by bending the ends of these metal plates. The rising portion 420 may be configured as a separate member from the flat surface portion 410 and may be attached to the flat surface portion 410. Since the rising portion 420 is generally provided for adjusting the directivity, it may be provided as needed.

The arrangement of the antennas 10 and 20 will be described.
The low frequency band antennas 10-1 to 10-3 are arranged at equal intervals in the y direction at the center of the flat surface portion 410 of the reflector 400 in the x direction. The high frequency band antennas 20-1 to 20-10 are also arranged at equal intervals in the y direction at the center of the flat surface portion 410 of the reflector 400 in the x direction. That is, the arrangement of the antenna 20 is arranged so as to overlap the arrangement of the antenna 10. As an example, two adjacent antennas 20 are arranged in the antenna 10, and one antenna 20 is arranged between two adjacent antennas 10. That is, the interval between the arrangements of the antennas 20 is three times the interval between the arrangements of the antennas 10.

First, the antenna 10 will be described in the antenna 10-1. Hereinafter, the antenna 10-1 is referred to as an antenna 10.
The antenna 10 includes a reflector 400 and four antenna modules 100-1 to 100-4 (denoted as antenna module 100 when not distinguished) provided on the flat surface portion 410 of the reflector 400. Each antenna module 100 includes a dipole antenna 200 and a non-feeding element 300. The non-feeding element 300 is provided close to the dipole antenna 200 so as to face the dipole antenna 200.
Here, the dipole antenna 200 in the antenna module 100-1 is an example of the first dipole antenna, the dipole antenna 200 in the antenna module 100-2 is an example of the second dipole antenna, and the dipole antenna 200 in the antenna module 100-3 is the first. An example of the dipole antenna of No. 3, and the dipole antenna 200 in the antenna module 100-4 is an example of the fourth dipole antenna.

The four dipole antennas 200 are arranged at each corner of the virtual quadrangle 11 shown by the broken line (see FIG. 2B). A pair of radiating portions (radiating portion 210 and radiating portion 220 shown in FIG. 3 to be described later) of each dipole antenna 200 are arranged along the four sides of the quadrangle 11. Further, the four non-feeding elements 300 are provided inside the quadrangle 11 formed by the four dipole antennas 200.

The antenna module 100-1 and the antenna module 100-3 are provided so as to face each other, and transmit and receive the polarization of −45 ° in the low frequency band. On the other hand, the antenna module 100-2 and the antenna module 100-4 are provided so as to face each other, and transmit and receive + 45 ° polarization in the low frequency band. In addition, −45 ° is a direction inclined by 45 ° in the y direction from the x direction, and + 45 ° is a direction inclined by 45 ° in the y direction from the −x direction. That is, the antenna module 100 transmits and receives the polarization along the diagonal direction of the quadrangle 11. Here, the polarization of + 45 ° is an example of the first polarization, and the polarization of −45 ° is an example of the second polarization.

The antenna 10 transmits and receives both polarizations of ± 45 ° by four antenna modules 100 (antenna modules 100-1, 100-2, 100-3, 100-4).
The configuration of the dipole antenna 200 and the non-feeding element 300 will be described in detail later.

Next, the antenna 20 will be described in the antenna 20-6. The antenna 20-6 is referred to as an antenna 20.
The antenna 20 includes a reflector 400 and dipole antennas 21-1 and 21-2 (referred to as dipole antenna 21 when not distinguished) provided on the flat surface portion 410 of the reflector 400. The dipole antennas 21-1 and 21-2 intersect each other to form a cross dipole structure. The dipole antenna 21-1 transmits and receives the polarization of −45 ° in the high frequency band, and the dipole antenna 21-2 transmits and receives the polarization of + 45 ° in the high frequency band. That is, the antenna 20 transmits and receives both polarizations of ± 45 ° by the two dipole antennas 21 constituting the cross dipole structure.

The dipole antenna 21 includes a radiation unit and a balun unit. The radiating portion is a portion that radiates radio waves, and the balun portion is a portion that sets a distance from the reflector 400. Here, the radiation portion and the balun portion are collectively referred to as a dipole antenna 21.

The dipole antenna 21 shown in FIGS. 2 (a) and 2 (b) is provided with an opening in the radiation portion. The antenna 20 has a circular outer edge in the xy plane. The antenna 20 is composed of a conductive member in which the radiation portion and the balun portion of the two dipole antennas 21 (dipole antennas 21-1 and 21-2) are integrated. For example, the antenna 20 is integrally formed of a conductive metal such as aluminum or copper by die casting or the like.

Further, as shown in FIG. 2A, two partition plates 430 and 11 partition plates 440 are provided on the reflector 400 around the antenna 20. The two partition plates 430 are provided on both sides of the array of antennas 20 so as to extend in the + y direction. Further, 11 partition plates 440 are provided in the x direction between the partition plates 430 so as to separate the antennas 20 respectively. The partition plates 430 and 440 are made of the same members as the members constituting the reflector 400.

The high frequency band antenna 20 does not have to have the above configuration. For example, a dipole antenna having a linear radiating portion may have a cross dipole structure. Further, similarly to the antenna 10 in the low frequency band, four dipole antennas may be arranged at each corner of the quadrangle. Further, it is not necessary to provide either one or both of the partition plates 430 and 440.

(Antenna module 100)
FIG. 3 is a diagram illustrating the antenna module 100. 3A is a perspective view, FIG. 3B is a plan view, and FIG. 3C is a side view. In FIG. 3, one antenna module 100 is taken out from the antenna 10 in the array antenna 3 shown in FIG. 2 and shown.
As described above, the antenna module 100 includes a dipole antenna 200 and a non-feeding element 300. Hereinafter, the dipole antenna 200 and the non-feeding element 300 will be described separately.

(Dipole antenna 200)
The dipole antenna 200 includes radiation portions 210 and 220 and a balun portion 230. Radiating units 210 and 220 form a dipole to transmit and receive radio waves. The balun portion 230 sets the distance between the radiation portions 210 and 220 and the reflector 400.

(Radiation parts 210 and 220 of the dipole antenna 200)
First, the radiation units 210 and 220 will be described. Here, the virtual intermediate point (indicated by) between the radiation unit 210 and the radiation unit 220 is defined as the center O of the dipole antenna 200. The radiating portion 210 and the radiating portion 220 extend from the center O of the dipole antenna 200 on opposite sides to each other.

The radiating portion 210 includes an extending portion 211 and a bent portion 212 from the center O side. Here, the stretched portion 211 extends from the center O side in parallel with the reflector 400. The bent portion 212 is a portion bent from the end portion of the extended portion 211 opposite to the center O side toward the reflector 400 side.
Similarly, the radiating portion 220 includes an extending portion 221 and a bent portion 222 from the center O side. The stretched portion 221 is a portion extending parallel to the reflector 400 from the center O side. The bent portion 222 is a portion bent from the end portion of the extended portion 221 opposite to the center O side toward the reflector 400 side.

Here, the extension portion 211 of the radiation portion 210 will be described.
The stretched portion 211 includes a first stretched portion 211a, a second stretched portion 211b, a first edge portion 211c, and a second edge portion 211d.
The first stretched portion 211a is composed of a long plate-shaped member whose surface is parallel to the reflector 400, and stretches from the center O side. That is, in the first stretched portion 211a, one end of the plate-shaped member in the longitudinal direction is located on the center O side. The second stretched portion 211b is composed of a long plate-shaped member whose surface is parallel to the reflector 400, and is connected to the other end of the first stretched portion 211a in the longitudinal direction. That is, the first stretched portion 211a and the second stretched portion 211b are made of plate-shaped members having the same width with their surfaces parallel to the reflector 400. The center line of the second stretched portion 211b is bent so as to intersect the center line of the first stretched portion 211a at an angle of 45 °.

The first edge portion 211c is provided so as to bend at a right angle to the reflector 400 side from one edge in the longitudinal direction of the first extension portion 211a. The second edge portion 211d is provided so as to bend at a right angle to the reflector 400 side from one edge in the longitudinal direction of the second extension portion 211b. The one side in the longitudinal direction of the first stretched portion 211a and the one side in the longitudinal direction of the second stretched portion 211b are the sides having a small angle formed by the first stretched portion 211a and the second stretched portion 211b. The first edge portion 211c and the second edge portion 211d are continuously provided.
The first edge portion 211c and the second edge portion 211d have a width W. As an example, the width W is set to an electric length corresponding to _0.025 λ 0 L with respect to the wavelength λ _{0 L.}

Next, the bent portion 212 of the radiating portion 210 will be described.
The bent portion 212 includes a first bent portion 212a and a second bent portion 212b.
The first bent portion 212a is composed of a plate-shaped member, one end thereof is connected to the end portion opposite to the center O side of the stretched portion 211, that is, the end portion of the second stretched portion 211b, and the other end portion is reflected. It is configured to bend towards the plate 400. Here, the surface of the first bent portion 212a is a surface perpendicular to the reflector 400. The second bent portion 212b is composed of a plate-shaped member, is connected to the other end of the first bent portion 212a, and is configured to be bent diagonally toward the reflector 400. The direction of the diagonal bend is the balun portion 230 side, which will be described later. The first bent portion 212a is connected to the second edge portion 211d.

Next, the radiation unit 220 will be described.
The radiating portion 220 includes a stretching portion 221 and a bent portion 222 as described above.
Like the stretched portion 211, the stretched portion 221 includes a first stretched portion 221a, a second stretched portion 221b, a first edge portion 221c, and a second edge portion 221d. The bent portion 222 includes a first bent portion 222a and a second bent portion 222b, similarly to the bent portion 212.

The first stretched portion 221a is composed of a long plate-shaped member whose surface is parallel to the reflector 400, and stretches from the center O side to the opposite side of the first stretched portion 211a. Here, the center line of the first stretched portion 211a and the center line of the first stretched portion 221a are on a straight line.
The second stretched portion 221b, the first edge portion 221c, and the second edge portion 221d are formed on a vertical surface including the center O with respect to the straight line connecting the center line of the first stretched portion 211a and the center line of the first stretched portion 221a. On the other hand, it is provided symmetrically with the second stretched portion 211b, the first edge portion 211c, and the second edge portion 211d described above. Similarly, the bent portion 222 is symmetrical to the above-mentioned bent portion 212 with respect to the surface including the center O perpendicular to the straight line connecting the center line of the first extended portion 211a and the center line of the first extended portion 221a. It is provided in. Therefore, the description of these will be omitted.

The first bent portion 222a (same for the first bent portion 212a) has a length L1, and the second bent portion 222b (same for the second bent portion 212b) has a length L2. There is. As an example, the length L1 is set to the electric length corresponding to 0.051λ _0L with respect to the wavelength λ _0L , and the length L2 is set to the electric length corresponding to 0.046λ _0L with respect to the wavelength λ _0L . There is. Further, the first bent portion 222a (the same applies to the first bent portion 212a) and the second bent portion 222b (the same applies to the second bent portion 212b) form an angle θ. As an example, the angle θ is 150 °.

Here, the center line of the second stretched portion 211b of the stretched portion 211 and the center line of the second stretched portion 221b of the stretched portion 221 intersect at 90 °.

Then, from the tip of the bent portion 212 of the radiating portion 210 to the tip of the bent portion 222 of the radiating portion 220, the radiating portion 210 (stretched portion 211 and the bent portion 212) and the radiating portion 220 (folded with the extending portion 221). The length along the curved portion 221) is set to an electric length corresponding to 1/2 of the wavelength λ _0L in the low frequency band. The length along the radiating portion 210 (stretched portion 211 and the bent portion 212) and the radiating portion 220 (stretched portion 221 and the bent portion 221) means the length of the center line.

In a dipole antenna in which the radiating portion 210 and the radiating portion 220 are linear, the length between both tips is set to an electric length corresponding to 1/2 of the wavelength λ _{0 L.} However, when the frequency becomes low, the wavelength λ _0L becomes long, so that the length between the two tips of the radiating portion 210 and the radiating portion 220 of the dipole antenna becomes large. Therefore, the planar shape of the dipole antenna 200 becomes large, and the planar shape of the antenna module 100 becomes large. That is, the planar shape of the antenna 10 becomes large.

In the dipole antenna 200 of the present embodiment, in the radiation portion 210, the extension portion 211 is provided with a second extension portion 211b bent from the first extension portion 211a, and a bent portion 212 is provided. Similarly, in the radiating portion 220, the stretched portion 221 is provided with a second stretched portion 221b bent from the first stretched portion 221a, and is provided with a bent portion 222. As a result, the planar shape of the dipole antenna 200 is reduced while the electric length between the two tips of the radiation portion 210 and the radiation portion 220 of the dipole antenna 200 is equivalent to 1/2 of the wavelength λ _0L in the low frequency band. The planar shape of the antenna module 100 is reduced.

Here, in the radiation portion 210, the first stretched portion 211a, the second stretched portion 211b, the first edge portion 211c and the second edge portion 211d are provided, but the first stretched portion 211a, the second stretched portion 211b and the first Only one of the edge portion 211c and the second edge portion 211d may be provided. The same applies to the radiation unit 220.

(Balun part 230 of dipole antenna 200)
Next, the balun portion 230 will be described.
The balun portion 230 includes support portions 231 and 232 and a fixing portion 233.
The support portion 231 includes a vertical portion 231a, an inclined portion 231b, and an edge portion 231c. The vertical portion 231a is composed of a plate-shaped member, one end of which is connected to the end of the extending portion 211 of the radiating portion 210 on the center O side, and is a portion bent 90 ° toward the reflector plate 400 side. The inclined portion 231b is a portion connected to the other end of the vertical portion 231a and extending toward the reflector 400 while being inclined with respect to the surface of the reflector 400. The edge portion 231c is a portion provided perpendicular to the vertical portion 231a and the inclined portion 231b along one edge of the vertical portion 231a and the inclined portion 231b. It should be noted that one edge of the vertical portion 231a and the inclined portion 231b is the opposite side to the side where the support portion 232 is provided. The edge portion 231c is connected to the first edge portion 211c of the radiation portion 210.
That is, one side of the balun portion 230 is connected to the radiation portions 210 and 220, and the other side is connected to the flat surface portion 410 of the reflector 400.

The support portion 232 includes a vertical portion 232a, an inclined portion 232b, and an edge portion 232c. The vertical portion 232a, the inclined portion 232b, and the edge portion 232c are vertical portions with respect to the surface including the center O perpendicular to the straight line connecting the center line of the first stretched portion 211a and the center line of the first stretched portion 221a described above. It is provided symmetrically with the 231a, the inclined portion 231b, and the edge portion 231c. Therefore, the description of these will be omitted.

The end portions of the support portions 231 and 232 on the reflector 400 side are connected by a plate-shaped fixing portion 233. The fixing portion 233 is a member for fixing the dipole antenna 200 to the reflector 400.

The length of the balun portion 230 is set to the length of the radiation portion 210 or the radiation portion 220 and the reflector 400. The balun portion 230 is set so that the length from the radiating portion 210 to the radiating portion 220 corresponds to an electric length of 1/2 of the wavelength λ _0L . However, the lower the frequency, the longer the wavelength λ _0L . Therefore, if the support portions 231 and 232 of the balun portion 230 are configured to be perpendicular to the reflector 400, the balun portion 230 becomes high. That is, the height of the dipole antenna 200 from the reflector 400 becomes high, and the antenna module 100 becomes high.

Therefore, in the dipole antenna 200 of the present embodiment, the inclined portion 231b is provided on the support portion 231 of the balun portion 230, and the inclined portion 232b is provided on the support portion 232. As a result, the electric length of the balun portion 230 of the dipole antenna 200 is set to a value corresponding to 1/2 of the wavelength λ _0L in the low frequency band, while the dipole antenna 200 is set to a low posture so that the height of the antenna module 100 does not increase. I have to. The direction of inclination of the inclined portions 231b and 232b will be described later. The vertical portion 231a in the support portion 231 and the vertical portion 232a in the support portion 232 may not be provided, and the support portion 231 may be configured by the inclined portion 231b and the support portion 232 may be configured by the inclined portion 232b.

Here, the dipole antenna 200 is composed of a conductive member in which the radiation portions 210 and 220 and the balun portion 230 are integrated. For example, the dipole antenna 200 is integrally formed by die casting or the like with a conductive metal such as aluminum or copper. In this case, the dipole antenna 200 is fixed to the reflector 400 by penetrating a bolt through the opening provided in the fixing portion 233 and the opening provided in the reflector 400. By doing so, it becomes easy to fix the dipole antenna 200 to the reflector 400.

The support portion 231 of the balun portion 230 is provided with a vertical portion 231a, an inclined portion 231b, and an edge portion 231c. However, the vertical portion 231a and the inclined portion 231b may be provided, and the edge portion 231c may not be provided. It is not necessary to provide the vertical portion 231a and the inclined portion 231b by providing the 231c. The same applies to the support portion 232.

The power supply to the dipole antenna 200 is performed as follows.
A coaxial cable used for transmitting and receiving signals is inserted from the back surface side of the reflector 400 through an opening (not shown) provided in the reflector 400. The coaxial cable is arranged along the edge portion 231c of the support portion 231 in the balun portion 230. Then, the outer conductor of the coaxial cable is connected to an opening (not shown) provided in the extension portion 211 (first extension portion 211a) of the radiation portion 210. On the other hand, the inner conductor of the coaxial cable passes through the opening provided in the extending portion 211 and passes through the connecting terminal 240 provided in the radiating portion 220 via the conductive member (connecting member 250 in FIG. 2A). Is connected. In this way, a signal is supplied to the dipole antenna 200 by a coaxial cable.
The above is the case of the antenna modules 100-1 and 100-3 that transmit and receive -45 ° polarization, and the antenna modules 100-3 and 100-4 that transmit and receive + 45 ° polarization have different feeding methods. The opposite is true.

(Passive repeater 300)
The non-feeding element 300 is composed of a plate-shaped member whose surface is parallel to the reflector 400, and includes a first stretched portion 310, a second stretched portion 320, and a third stretched portion 330.
As can be seen from FIGS. 3A and 3B, the non-feeding element 300 is provided close to the radiating portions 210 and 220 of the dipole antenna 200. Here, the non-feeding element 300 is provided in the same plane as the first stretched portion 211a and the second stretched portion 211b of the radiating portion 210, and the first stretched portion 221a and the second stretched portion 221b of the radiating portion 220. There is. The non-feeding element 300 does not have to be provided in the same plane as these elements.

As shown in FIG. 3B , the first stretched portion 310 of the non-feeding element 300 is the first stretched portion 211a of the stretched portion 211 in the radiating portion 210 of the dipole antenna 200 and the first stretched portion 221 in the radiating portion 220. 1 It is provided in parallel with the stretched portion 221a. The second stretched portion 320 of the non-feeding element 300 is provided in parallel with the second stretched portion 211b of the stretched portion 211 in the radiating portion 210. The third stretched portion 330 of the non-feeding element 300 is provided in parallel with the second stretched portion 221b of the stretched portion 221 in the radiating portion 220. That is, the second stretching portion 320 and the third stretching portion 330 in the non-feeding element 300 follow the second stretching portion 211b bent in the radiating portion 210 of the dipole antenna 200 and the second stretching portion 221b bent in the radiating portion 220. As described above, it is provided so as to be bent from the first stretched portion 310.

The non-feeding element 300 is made of a conductive member. For example, it may be formed of a metal plate such as aluminum or copper, or may be formed of a copper foil provided on an insulating substrate such as a glass epoxy, a glass polyimide substrate, a fluorine substrate, or a ceramic substrate.

(Antenna 10)
Next, the antenna 10 will be described in detail.
FIG. 4 is a diagram illustrating the antenna 10. 4 (a) is a perspective view, FIG. 4 (b) is a plan view, and FIG. 4 (c) is a side view. In FIG. 4, the antenna 10-1 is taken out from the array antenna 3 shown in FIG. 2 and shown. Hereinafter, the antenna 10-1 is referred to as an antenna 10.
As shown in FIG. 4B, the antenna 10 includes four antenna modules 100 (antenna modules 100-1 to 100-4). The four antenna modules 100 are arranged at each corner of the virtual quadrangle 11 shown by the broken line. As described above, since the center line of the second extending portion 211b of the radiating portion 210 in the dipole antenna 200 and the center line of the second extending portion 221b of the radiating portion 220 form 90 °, the radiating portion in the dipole antenna 200 The second stretched portion 211b of the 210 and the second stretched portion 221b of the radiating portion 220 are arranged parallel to the sides of the quadrangle 11. That is, by bending the second stretched portion 211b of the radiating portion 210 from the first stretched portion 211a and bending the second stretched portion 221b of the radiating portion 220 from the first stretched portion 221a, the antenna is compared with the case where it is not bent. The planar shape of 10 is smaller.

The four non-feeding elements 300 are provided inside the quadrangle formed by the radiating portions 210 and 220 of the four dipole antennas 200.

Further, as shown in FIG. 4C, the bent portion 212 in the radiating portion 210 of the antenna module 100-1 and the bent portion 222 in the radiating portion 220 of the adjacent antenna module 100-2 face each other. .. In particular, the first bent portion 212a of the bent portion 212 in the radiating portion 210 of the antenna module 100-1 has a planar shape perpendicular to the reflector 400, and here it is a flat surface. Further, the first bent portion 222a of the bent portion 222 in the radiation portion 220 of the antenna module 100-2 has a surface perpendicular to the reflector 400. Therefore, the first bent portion 212a of the bent portion 212 in the radiating portion 210 of the antenna module 100-1 is parallel to the first bent portion 222a of the bent portion 222 in the radiating portion 220 of the antenna module 100-2. Are in a parallel state and face each other to be capacitively coupled. Here, the first bent portion 212a of the bent portion 212 in the radiating portion 210 and the first bent portion 222a of the bent portion 222 in the radiating portion 220 are examples of the connecting portion.

As can be seen from FIG. 4A, the antenna module 100-1 and the antenna module 100-2 transmit and receive different polarizations from each other. That is, the adjacent antenna modules 100 are capacitively coupled via the dipole antenna 200 that transmits and receives different polarizations.

Then, as shown in FIG. 4 (c), the balun portion 230 of the dipole antenna 200 is a quadrangle 11 formed by the outer edges of the four dipole antennas 200 having the inclined portion 231b of the support portion 231 and the inclined portion 232b of the support portion 232. , It is designed to incline toward the outside.
By doing so, the area surrounded by the four antenna modules 100 is widened. As a result, as shown in FIG. 2, it is easy to arrange the antenna 20 in the high frequency band in the area surrounded by the antenna 10 in the low frequency band.

It is conceivable that the four dipole antennas 200 included in the antenna module 100 are integrally formed of a conductive member. However, if the four dipole antennas 200 are integrally configured, the antenna 20 in the high frequency band used in combination may be restricted. That is, since the area surrounded by the four antenna modules 100 is fixed, it becomes difficult to change the size and the pitch of the arrangement of the antenna 20. Therefore, by individually configuring the four dipole antennas 200, the position where the antenna module 100 on the low frequency band side is arranged can be adjusted, and the size and arrangement of the antennas 20 in the high frequency band to be combined can be changed. I am doing it.

Next, the effect of capacitive coupling between the antenna modules 100 will be described.
FIG. 5 is an example and a comparative example for explaining the effect of capacitive coupling. FIG. 5A is an example consisting of four antenna modules 100, and FIG. 5B is a comparative example consisting of one antenna module 100.
An embodiment is an antenna 10 in the present embodiment having four antenna modules 100, and a comparative example is an antenna 10'with one antenna module 100 (antenna module 100-4 in FIG. 4A). ..

FIG. 6 is a diagram showing the evaluation results of return loss in the examples and comparative examples shown in FIG. Here, the S parameter S11, which is the ratio of the reflected wave to the input wave when the dipole antenna 200 is fed, was evaluated. In the embodiment of FIG. 5A, power was supplied to one dipole antenna 200 out of the four sets of antenna modules 100.

As shown in FIG. 6, in the example, S11 is significantly reduced as compared with the comparative example. Then, in the example, in the 700 MHz band (range from 611 MHz to 897 MHz), S11 is obtained to be −14 dB or less. This is a frequency band in which the voltage standing wave ratio (VSWR) is 1.5 or less. Therefore, it is shown that the specific bandwidth is 38% when VSWR is 1.5 or less (VSWR ≦ 1.5).
On the other hand, in the comparative example, S11 in the range of 611 MHz to 897 MHz is −7 dB or less.

In the embodiment, the decrease in S11 is due to the capacitive coupling between the dipole antennas 200 in the adjacent antenna modules 100.
In particular, the first bending portion 212a of the bending portion 212 in the radiation portion 210 of the dipole antenna 200 in the antenna module 100 and the first bending portion 222 in the radiation portion 220 of the dipole antenna 200 in the adjacent antenna module 100. This is because the surface of the portion 222a is configured to be in a parallel state to facilitate capacitive coupling.

If the capacitive coupling becomes too strong, the polarization coupling characteristics may deteriorate. Therefore, as shown in FIGS. 3 (a) and 3 (c) and FIG. 4 (c), in order to suppress the capacitive coupling from becoming too strong, the bent portion 212 in the radiating portion 210 of the dipole antenna 200 is provided. The second bent portion 212b and the second bent portion 222b are provided at the bent portion 222 in the radiating portion 220 of the adjacent dipole antenna 200 so that they are separated from each other. As a result, the electric length of the dipole antenna 200 composed of the radiation unit 210 and the radiation unit 220 is set to 1/2 of the wavelength λ _0L , and the capacitive coupling amount can be adjusted. That is, the capacitive coupling amount is adjusted by adjusting the areas of the first bent portions 212a and 222a facing each other in the parallel state. The second bent portions 212b and 222b may or may not be provided as needed.

Further, the first edge portion 211c and the second edge portion 211d of the radiation portion 210 and the first edge portion 221c and the second edge portion 221d of the radiation portion 220 are also related to the capacitive coupling between the two adjacent dipole antennas 200. do. Therefore, the width W of the first edge portion 211c, the second edge portion 211d, the first edge portion 221c, and the second edge portion 221d may be adjusted to adjust the capacitive coupling amount between the adjacent dipole antennas 200.

FIG. 7 is a diagram illustrating an example of deformation of the shapes of the bent portion 212 of the radiating portion 210 and the bent portion 222 of the radiating portion 220 facing each other. 7 (a) is the present embodiment described so far, FIG. 7 (b) is a modified example 1, FIG. 7 (c) is a modified example 2, and FIG. 7 (d) is a modified example 3. .. Here, the bent portions 212 and 222 of the dipole antenna 200 in the adjacent antenna modules 100-1 and 100-2 are shown.
In the modification 1 shown in FIG. 7 (b), in FIG. 7 (a), the first bent portion 212a and the second bent portion 212b in the bent portion 212 are exchanged, and the first bending in the bent portion 222 is performed. The portion 222a and the second bent portion 222b are exchanged. Even in this way, the electric lengths of the radiation units 210 and 220 are set to predetermined values and are capacitively coupled.

In the modification 2 shown in FIG. 7 (c), the bent portions 212 and 222 in the modification 1 shown in FIG. 7 (b) are inverted in the z direction. Even in this way, the electric lengths of the radiation units 210 and 220 are set to predetermined values and are capacitively coupled. However, the height (length in the z direction) of the antenna 10 becomes high.

In the modification 3 shown in FIG. 7 (d), the bent portions 212 and 222 in the present embodiment shown in FIG. 7 (a) are inverted in the z direction. Even in this way, the electric lengths of the radiation units 210 and 220 are set to predetermined values and are capacitively coupled. However, the height (length in the z direction) of the antenna 10 becomes high.

In this specification, the array antenna 3, the antennas 10, 20, and the antenna module 100 have been described as a polarization shared antenna that transmits and receives radio waves of ± 45 ° polarization, but the orientations of the antennas 10, 20, and the antenna module 100 are indicated. It may be changed to be a polarization shared antenna for transmitting and receiving vertically polarized waves and horizontally polarized radio waves.

Further, various modifications may be made as long as it does not contradict the gist of the present invention.

1, 1-1 to 1-3 ... Sector antenna, 2 ... Iron tower, 3 ... Array antenna, 4 ... Radome, 5 ... Cell, 6, 6-1 to 6-3 ... Sector, 8, 8-1 to 8- 4 ... Transmission / reception cable, 10, 10', 10-1 to 10-3, 20, 20-1 to 20-10 ... Antenna, 21, 21-1, 21-2, 200 ... Dipole antenna, 100, 100-1 ~ 100-4 ... Antenna module, 210, 220 ... Radiating part, 211, 221 ... Stretched part, 211a, 221a ... First stretched part, 211b, 221b ... Second stretched part, 211c, 221c ... First edge part, 211d , 221d ... 2nd edge portion, 212, 222 ... Bent part, 212a, 222a ... 1st bent part, 212b, 222b ... 2nd bent part, 230 ... Balun part, 231, 232 ... Support part, 231a, 232a ... Vertical part, 231b, 232b ... Inclined part, 233 ... Fixed part, 240 ... Connection terminal, 250 ... Connection member, 300 ... Non-feeding element, 400 ... Reflector, 410 ... Flat part, 420 ... Rising top

Claims (16)

A reflective member with a flat surface and
It has a pair of radiating portions and a balun portion on which one side is connected to the opposite portion of the radiating portion and the other side is connected to the reflecting member, and the pair is provided on the flat surface portion of the reflecting member. A first dipole antenna that transmits and receives radio waves of the first polarization by the radiation unit,
It has a pair of radiating portions and a balun portion whose one side is connected to the opposite portion of the radiating portion and the other side is connected to the reflecting member, and is provided on the flat surface portion of the reflecting member and is provided in the pair. A second dipole antenna for transmitting and receiving radio waves having a second polarization different from that of the first polarization by a radiation unit is provided.
In the first dipole antenna and the second dipole antenna, the opposite side of each pair of the radiation portions on the opposite side is bent to the plane portion side or the opposite side of the plane portion side of the reflection member. The bent portion has a planar first bent portion in which the first dipole antenna and the second dipole antenna face each other and are capacitively coupled to each other, and the bent portion is formed on the reflective member. An antenna characterized by including a second bent portion that is bent diagonally toward the balun portion . The antenna according to claim 1, further comprising two non-feeding elements arranged close to each of the first dipole antenna and the second dipole antenna. It has a pair of radiating portions and a balun portion on which one side is connected to the opposite portion of the radiating portion and the other side is connected to the reflecting member, and the pair is provided on the flat surface portion of the reflecting member. A third dipole antenna that transmits and receives radio waves of the first polarization by the radiation unit, and
It has a pair of radiating portions and a balun portion on which one side is connected to the opposite portion of the radiating portion and the other side is connected to the reflecting member, and the pair is provided on the flat surface portion of the reflecting member. Further, a fourth dipole antenna for transmitting and receiving the radio wave of the second polarization by the radiation unit is provided.
In the first dipole antenna, the second dipole antenna, the third dipole antenna, and the fourth dipole antenna, the opposite side of each pair of the radiation portions on the opposite side is the plane portion of the reflection member. The bent portion has a bent portion on the side or the opposite side of the flat portion side, and the bent portion has a planar first bent portion that is capacitively coupled to each other by facing each other and the reflection portion. The antenna according to claim 1, further comprising a second bent portion that bends diagonally toward the balun portion with respect to the member . The first dipole antenna, the second dipole antenna, the third dipole antenna, and the fourth dipole antenna are provided at the corners of a virtually provided quadrangle.
The radiation portions of the first dipole antenna, the second dipole antenna, the third dipole antenna, and the fourth dipole antenna are from a portion parallel to the diagonal line of the square and an end portion of the portion. The antenna according to claim 3, further comprising a stretched portion having a portion that bends and stretches along a side. The radiation portions of the first dipole antenna, the second dipole antenna, the third dipole antenna, and the fourth dipole antenna each transmit and receive radio waves of polarization along the diagonal direction of the square. The antenna according to claim 4, wherein the antenna is characterized by the above. The first dipole antenna, the second dipole antenna, and the third dipole antenna are on the side surrounded by the first dipole antenna, the second dipole antenna, the third dipole antenna, and the fourth dipole antenna. The antenna according to claim 4, further comprising four non-feeding elements arranged close to each of the dipole antenna of the above and the fourth dipole antenna. The first dipole antenna, the second dipole antenna, the third dipole antenna, and the fourth dipole antenna are provided at the corners of a virtually provided quadrangle.
The balun portion of each of the first dipole antenna, the second dipole antenna, the third dipole antenna, and the fourth dipole antenna is connected to the reflection member on the other side of the first dipole antenna. The antenna according to claim 3, wherein the antenna is provided so as to be inclined outward on the side surrounded by the second dipole antenna, the third dipole antenna, and the fourth dipole antenna. A reflective member with a flat surface and
It has a pair of radiating portions and a balun portion on which one side is connected to the opposite portions of the radiating portion and the other side is connected to the reflecting member, and the pair of the radiating portions makes the first of the first frequency band. The first dipole antenna and the third dipole antenna that transmit and receive the radio wave of the polarization of the above, and the radio wave of the second polarization different from the first polarization of the first frequency band by the pair of the radiation units. A plurality of first antennas each provided with a second dipole antenna and a fourth dipole antenna for transmission and reception, and arranged in a row on the plane portion of the reflective member.
A plurality of second antennas arranged with respect to the plane portion of the reflecting member along the arrangement of the plurality of first antennas, each transmitting and receiving radio waves in a second frequency band higher than the first frequency band. With an antenna,
In the first dipole antenna, the second dipole antenna, the third dipole antenna, and the fourth dipole antenna, the opposite side of each pair of the radiation portions on the opposite side is the plane portion of the reflection member. An array antenna having a bent portion on one side or the opposite side of the flat portion side, and having a planar joint portion of the bent portion facing each other so as to be capacitively coupled to each other. The array antenna according to claim 8, wherein the arrangement of the plurality of second antennas is arranged so as to overlap with the arrangement of the plurality of first antennas with respect to the plane portion of the reflection member. .. The array antenna according to claim 9, wherein the distance between the arrangements of the plurality of first antennas is three times the distance between the arrangements of the plurality of second antennas. The two second antennas are arranged in the area surrounded by the first dipole antenna, the second dipole antenna, the third dipole antenna and the fourth dipole antenna in the first antenna. The array antenna according to claim 9 or 10, wherein the antenna is made of a dipole antenna. It has a reflective member having a flat surface portion, a pair of radiating portions and a balun portion in which one side is connected to a pair of opposite portions of the radiating portion and the other side is connected to the reflective member. A first dipole antenna that transmits and receives radio waves of one polarization and a second dipole antenna that transmits and receives radio waves of a second polarization different from the first polarization by a pair of the radiation units, respectively. A plurality of antennas provided are an array antenna provided on the plane portion of the reflection member and an array antenna provided.
With a cover covering the array antenna,
The first dipole antenna and the second dipole antenna are bent so that the opposite side of each pair of the radiation portions on the opposite side is the plane portion side of the reflection member or the side opposite to the plane portion side. It has a bent portion, and the bent portion includes a planar first bent portion in which the first dipole antenna and the second dipole antenna face each other and are capacitively coupled to each other, and the reflective member. A sector antenna characterized by including a second bent portion that is bent diagonally toward the balun portion . A pair of radiating parts and
A balun portion, one side connected to a pair of opposite portions of the radiation portion and the other side connected to a reflective member, is provided.
The opposite side of the pair of the radiating portions on the opposite side has a bent portion bent toward the reflecting member side or the opposite side of the reflecting member side, and the bent portion is provided adjacent to another radiating portion. A dipole antenna characterized by including a planar first bent portion that is capacitively coupled by facing each other and a second bent portion that is obliquely bent toward the balun portion with respect to the reflective member . Each of the pair of radiation portions comprises a stretched portion having a portion extending from the opposite portion to the opposite side and a portion bending and extending from the end portion of the portion.
The dipole antenna according to claim 13, wherein the bending direction of the bending and stretching portion is the same side in the pair of the radiating portions. The dipole antenna according to claim 14, wherein each of the pair of the radiation portions includes an edge portion provided so as to extend from one edge of the extension portion to the reflection member. The dipole antenna according to claim 14, wherein the balun portion includes a portion that is inclined in a direction opposite to the bending direction of the stretched portion.

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