WO2015133458A1

WO2015133458A1 - Array antenna and sector antenna

Info

Publication number: WO2015133458A1
Application number: PCT/JP2015/056173
Authority: WO
Inventors: 慎水村; 拓人中村; 張　鵬; 泰介井原; 裕之川合; 龍彦吉原
Original assignee: 日本電業工作株式会社
Priority date: 2014-03-04
Filing date: 2015-03-03
Publication date: 2015-09-11
Also published as: JP2015167337A; CN106030906A; JP6267005B2

Abstract

This array antenna (100) is provided with: a reflection plate (200); low-frequency-band dipole elements (110-1 to 110-3) arrayed in the vertical direction above the reflection plate (200); high-frequency-band dipole elements (120-1 to 120-6) similarly arrayed in the vertical direction above the reflection plate (200); and conductors (130-1 to 130-4) configured from a conductive material and similarly arrayed in the vertical direction above the reflection plate (200). The low-frequency-band dipole elements (110) and high-frequency-band dipole elements (120) are arrayed in an intermixed manner, and the conductors (130) are disposed at the side of the high-frequency-band dipole elements (120) at which the low-frequency-band dipole elements (110) are not disposed. As a result, in the transmission/reception of radio waves in a plurality of frequency bands, an effect of the transmission/reception of radio waves at one frequency band by an antenna element on the directivity or the like in another frequency band is suppressed.

Description

Array antenna and sector antenna

The present invention relates to an array antenna and a sector antenna.

As a mobile communication base station antenna (base station antenna), a plurality of sector antennas that transmit and receive radio waves for each sector set corresponding to the direction of transmitting and receiving radio waves are used in combination. As the sector antenna, an array antenna in which antenna elements such as a dipole antenna are arranged in an array may be used.

In Patent Document 1, a folded reflector having a width of about 0.25 wavelength or less formed by folding back both side portions, a metal plate provided on the folded reflector through a spacer, and supported on the metal plate. The first radiating element and the second radiating element, which are held at a predetermined height by the member and are linearly provided at predetermined intervals along the center of the front surface of the folded reflector, and the first radiating element and the second radiating element. A parasitic element provided in parallel with each other at a predetermined interval on each side of the radiating element, a feeding part provided in a substantially central part of the metal plate, and insulated on the metal plate. A feed line for supplying a feed signal from the feed unit to the first radiating element and the second radiating element; and the feed line, the first radiating element and the second radiating element provided in the feed line; Impedance matching impedance between ; And a Nsu conversion unit, the folding reflection plate and the first radiating element and the second directional antenna is set to about 0.09 wavelength spacing between the radiating elements have been described.

JP 2013-115460 A

By the way, a small array antenna capable of transmitting and receiving radio waves in different frequency bands may be required. At that time, when a plurality of antenna elements that transmit and receive radio waves in different frequency bands are arranged close to each other for miniaturization, the antenna elements that transmit and receive radio waves in one frequency band are used to transmit and receive radio waves in other frequency bands. It is required to have little influence on directivity in
An object of the present invention is to provide an array antenna and a sector antenna that can suppress influence on directivity in other frequency bands by an antenna element that transmits and receives radio waves in one frequency band by transmitting and receiving radio waves in a plurality of frequency bands. There is.

For this purpose, an array antenna to which the present invention is applied intersects a predetermined polarization direction at a first predetermined distance from the reflector made of a conductive material and a reflector. A plurality of first antenna elements arranged in a direction and transmitting / receiving polarized waves in the first frequency band, and a plurality of first antenna elements in the direction at a predetermined second distance from the reflector And a plurality of second antenna elements that transmit and receive a polarized wave in a second frequency band higher than the first frequency band, and a plurality of second antenna elements that are adjacent in the direction And a member that reflects radio waves transmitted and received by the second antenna element, when none of the plurality of first antenna elements is disposed between the two second antenna elements.
In such an array antenna, the member that reflects radio waves is a conductor made of a conductive material having a longitudinal direction in the polarization direction, and is provided at a predetermined third distance from the reflector. .
The conductor includes a member having a different direction from a member constituting the central portion at the end, and each member may be connected in a direct current manner.

Furthermore, the array antenna to which the present invention is applied may further include a third antenna element that transmits and receives a radio wave having a polarization orthogonal to the polarization in the first frequency band. In the second frequency band, You may further provide the 4th antenna element which transmits / receives the electromagnetic wave of the polarization orthogonal to polarization.
By doing in this way, it can be set as an array antenna for polarization sharing.

From another point of view, the sector antenna to which the present invention is applied crosses a predetermined polarization direction at a first predetermined distance from the reflector made of a conductive material and a reflector. A plurality of first antenna elements arranged in a direction to transmit and receive polarized radio waves in the first frequency band, and a plurality of first antennas in the direction at a predetermined second distance from the reflector. Among the plurality of second antenna elements arranged in a mixed manner with the elements and transmitting / receiving radio waves having a polarized wave in the second frequency band higher than the first frequency band, and the plurality of second antenna elements in the direction An array antenna comprising: a member that is disposed when any of the plurality of first antenna elements is not disposed between two adjacent second antenna elements, and that reflects a radio wave transmitted and received by the second antenna element. And And it includes a radome housing the antenna.
According to this configuration, the sector antenna can be made smaller than in the case without this configuration.

According to the present invention, there are provided an array antenna and a sector antenna that can suppress influence on directivity in other frequency bands by an antenna element that transmits and receives radio waves in one frequency band in an antenna that transmits and receives radio waves in a plurality of frequency bands. To do.

It is a figure which shows an example of the whole structure of the base station antenna for mobile communication with which 1st Embodiment is applied. (A) is a perspective view of a base station antenna, (b) is a figure explaining the example of installation of a base station antenna. It is a perspective view which shows an example of the sector antenna to which 1st Embodiment is applied. It is the top view which looked at the array antenna in the sector antenna to which 1st Embodiment is applied from the perpendicular direction with respect to the reflector, and sectional drawing of the perpendicular direction of a reflector. (A) is a plan view, and (b) is a cross-sectional view taken along line IIIb-IIIb in (a). In the array antenna to which the first embodiment is applied, the respective directivity in the vertical plane of two high frequency band dipole elements sandwiched between two low frequency band dipole elements is shown. is there. (A) shows the directivity of the high frequency band dipole element arranged on the upper side in the vertical direction, and (b) shows the directivity of the high frequency band dipole element arranged on the lower side in the vertical direction. It is a figure which shows the vertical in-plane directivity in the horizontal polarization of a high frequency band in the array antenna to which 1st Embodiment is applied, and the vertical in-plane directivity in the horizontal polarization of a low frequency band. (A) shows the vertical in-plane directivity in the horizontal polarization of the high frequency band, and (b) shows the vertical in-plane directivity in the horizontal polarization of the low frequency band. It is a perspective view which shows an example of the sector antenna to which 1st Embodiment is not applied. FIG. 4 is a plan view of an array antenna in a sector antenna to which the first embodiment is not applied as viewed from the direction perpendicular to the reflector and a sectional view in the direction perpendicular to the reflector. (A) is a plan view, and (b) is a cross-sectional view taken along the line VIIb-VIIb. In the array antenna to which the first embodiment is not applied, it is a diagram illustrating vertical in-plane directivities of two high frequency band dipole elements sandwiched between two low frequency band dipole elements. . (A) shows the directivity of the high frequency band dipole element arranged on the upper side in the vertical direction, and (b) shows the directivity of the high frequency band dipole element arranged on the lower side in the vertical direction. It is a figure which shows the vertical in-plane directivity in the horizontal polarization of a high frequency band in the array antenna to which 1st Embodiment is not applied, and the vertical in-plane directivity in the horizontal polarization of a low frequency band. (A) shows the vertical in-plane directivity in the horizontal polarization of the high frequency band, and (b) shows the vertical in-plane directivity in the horizontal polarization of the low frequency band. It is a figure explaining the factor from which the vertical in-plane directivity in the horizontal polarization of a high frequency band differs between the array antenna to which 1st Embodiment is applied, and the array antenna to which 1st Embodiment is not applied. (A) shows an array antenna to which the first embodiment is applied, and (b) shows an array antenna to which the first embodiment is not applied. It is a perspective view which shows an example of the sector antenna to which 2nd Embodiment is applied. It is the top view which looked at the array antenna in the sector antenna to which 2nd Embodiment is applied from the perpendicular direction of a reflector, and sectional drawing of the perpendicular direction of a reflector. (A) is a plan view, and (b) is a cross-sectional view taken along line XIIb-XIIb in (a). It is a perspective view which shows an example of the sector antenna to which 3rd Embodiment is applied. It is the top view which looked at the array antenna in the sector antenna to which 3rd Embodiment is applied from the perpendicular direction of the reflecting plate, and sectional drawing of the reflecting plate in the perpendicular direction. (A) is a plan view, and (b) is a cross-sectional view taken along line XIVb-XIVb in (a).

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.
[First Embodiment]
<Base station antenna 1>
FIG. 1 is a diagram illustrating an example of an overall configuration of a base station antenna 1 for mobile communication to which the first embodiment is applied. FIG. 1A is a perspective view of the base station antenna 1, and FIG. 1B is a diagram illustrating an installation example of the base station antenna 1.
As shown in FIG. 1A, the base station antenna 1 includes, for example, three sector antennas 10-1 to 10-3 held in a steel tower 20. Then, as shown in FIG. 1B, the base station antenna 1 transmits and receives radio waves (beams) in the cell 2. That is, the cell 2 is a range where radio waves transmitted by the base station antenna 1 reach and a range where the base station antenna 1 receives radio waves.
Each of the sector antennas 10-1 to 10-3 has a cylindrical shape (for example, a radome 500 in FIG. 2 described later), and the cylinder is provided substantially perpendicular to the ground.

As shown in FIG. 1B, the cell 2 includes a plurality of sectors 3-1 to 3-3 that are divided by angles in a horizontal plane orthogonal to the vertical direction. Each of the sectors 3-1 to 3-3 is provided corresponding to the three sector antennas 10-1 to 10-3 of the base station antenna 1. That is, when the sector antennas 10-1 to 10-3 radiate radio waves, the direction of the main lobe 11 in which the electric field of the radio waves output from each of the sector antennas 10-1 to 10-3 is large corresponds to the corresponding sector 3-1. It is suitable for ~ 3-3.
Here, when the sector antennas 10-1 to 10-3 are not distinguished from each other, they are referred to as sector antennas 10. In addition, when the sectors 3-1 to 3-3 are not distinguished from each other, they are represented as sector 3.

Note that the base station antenna 1 shown as an example in FIG. 1 includes three sector antennas 10-1 to 10-3 and sectors 3-1 to 3-3 corresponding thereto. However, the number of sector antennas 10 and sectors 3 may be less than 3 or greater than 3. In FIG. 1B, the sector 3 is configured by dividing the cell 2 into three equal parts (center angle 120 °). However, the sector 3 may not be equally divided, and any one sector 3 may be the other. The sector 3 may be wider or narrower than the sector 3.

Each sector antenna 10 has a low-frequency band dipole element provided in the sector antenna 10 (see low-frequency band dipole elements 110-1 to 110-3 in FIG. 2, which will be described later. A transmission / reception cable 31 for transmitting / receiving a transmission signal and a reception signal (transmission / reception signal) is provided. Further, transmission is made to a high-frequency band dipole element (see high-frequency band dipole elements 120-1 to 120-6 in FIG. 2 to be described later. When not distinguished from each other, they are referred to as high-frequency band dipole elements 120). A transmission / reception cable 32 for transmitting and receiving signals and reception signals (transmission / reception signals) is provided.
The transmission /

reception cables

31 and 32 are connected to a transmission / reception unit (not shown) that transmits and receives transmission / reception signals provided in a base station (not shown). The transmission /

reception cables

31 and 32 are, for example, coaxial cables.

In the following description, it is assumed that the base station antenna 1 mainly transmits radio waves, but the base station antenna 1 can receive radio waves due to the reversibility of the antennas. When receiving radio waves, for example, the signal flow may be reversed with the transmission signal as the reception signal.

The sector antenna 10 may also include a phase shifter for making the phases of transmission signals transmitted to the plurality of low frequency band dipole elements 110 included in the sector antenna 10 different from each other. Furthermore, you may provide the other phase shifter for making the phase of the transmission signal transmitted to each of several dipole element 120 for high frequency bands with which the sector antenna 10 is provided mutually differ.
By varying the phase of the transmission signal supplied to the plurality of low frequency band dipole elements 110 and / or the high frequency band dipole elements 120, the radiation direction of the radio wave (beam) is tilted from the horizontal plane to the ground direction (beam tilt). It is possible to set so that the radio wave does not reach outside the cell 2.

<Sector antenna 10>
FIG. 2 is a perspective view showing an example of the sector antenna 10 to which the first embodiment is applied. FIG. 2 shows a perspective view of one of the sector antennas 10-1 to 10-3 shown in FIG.
The sector antenna 10 includes an array antenna 100 and a radome 500 that is housed so as to enclose the array antenna 100.
In FIG. 2, the radome 500 is indicated by a broken line so that the array antenna 100 provided inside the radome 500 can be seen.

The array antenna 100 is arranged in a vertical direction on the reflector 200 and the reflector 200, and a low frequency band as an example of a first antenna element that transmits and receives radio waves in a low frequency band as an example of a first frequency band. As an example of the second dipole elements 110-1 to 110-3, which are similarly arranged in the vertical direction on the reflector 200, and transmit / receive radio waves in the high frequency band as an example of the second frequency band High frequency band dipole elements 120-1 to 120-6, and conductors 130-1 to 130-4 made of a conductive material arranged in the vertical direction on the reflector 200. When the conductors 130-1 to 130-4 are not distinguished from each other, they are referred to as conductors 130.
The low-frequency band dipole element 110, the high-frequency band dipole element 120, and the conductor 130 may be made of a conductive material. For example, a metal plate such as Al or Cu can be used. Moreover, not only plate shape but metal rods, such as Al and Cu, may be sufficient. Further, the low-frequency band dipole element 110, the high-frequency band dipole element 120, and the conductor 130 are formed of a metal layer such as Al or Cu provided on a substrate formed of a dielectric material such as glass epoxy. It may be.
In FIG. 2, the low-frequency band dipole element 110, the high-frequency band dipole element 120, and the conductor 130 are shown assuming a metal layer provided on a substrate made of a dielectric material such as glass epoxy. . In addition, the description of the board | substrate comprised with the dielectric material is abbreviate | omitted. The same applies to other figures.

The reflection plate 200 is a plate-like member made of a conductive material, and here, the longitudinal direction is provided in the vertical direction. For example, a metal plate such as Al or Cu can be applied to the reflecting plate. Further, a metal layer such as Al or Cu provided on a substrate made of a dielectric material such as glass epoxy may be used.

The low-frequency band dipole element 110 (low-frequency band dipole elements 110-1 to 110-3) is separated from the reflector 200 by a predetermined first distance (distance D _L in FIG. 3 described later) and vertically. They are arranged at intervals P _L in the direction. Each low frequency band dipole element 110 is provided such that a pair of element portions are arranged in the horizontal direction, and transmits and receives horizontally polarized waves.
The high frequency band dipole element 120 (high frequency band dipole elements 120-1 to 120-6) has a predetermined second distance from the reflector 200 on the side where the low frequency band dipole element 110 is provided. They are arranged at a distance P _H in the vertical direction at a distance (distance D _H in FIG. 3 described later). Each high-frequency band dipole element 120 is also provided so that a pair of element portions are arranged in the horizontal direction, and is arranged to transmit and receive horizontal polarization. Note that the interval P _L = 2 × the interval P _H.
The low frequency band dipole elements 110-1 to 110-3 and the high frequency band dipole elements 120-1 to 120-6 are provided with power supply means (not shown) and supplied with transmission / reception signals.
On the other hand, the conductors 130-1 to 130-4 have a predetermined third distance from the reflector 200 on the side where the low-frequency band dipole element 110 is provided from the reflector 200 (the distance in FIG. 3 described later). D _C ) are spaced apart. Each conductor 130 has a bar shape or a plate shape provided in the horizontal direction, and does not include a power feeding unit.

The low-frequency band dipole element 110, the high-frequency band dipole element 120, and the conductor 130 are perpendicular to each other at the point where the perpendicular line extending from the midpoint to the reflection plate 200 intersects the reflection plate 200. They are arranged in a straight line.
Two high frequency band dipole elements 120 are arranged between the two low frequency band dipole elements 110. For example, high frequency band dipole elements 120-2 and 120-3 are provided between the low frequency band dipole element 110-1 and the low frequency band dipole element 110-2.
The conductor 130 is disposed between two high-frequency band dipole elements 120 provided between the two low-frequency band dipole elements 110. For example, the conductor 130-2 includes a high frequency band dipole element 120-2 and a high frequency band dipole element 120-3 provided between two low frequency band dipole elements 110-1 and 110-2. It is provided between. The conductor 130-2 is disposed at a distance P _H / 2 from each of the high frequency band dipole elements 120-2 and 120-3.
That is, the low frequency band dipole element 110 and the high frequency band dipole element 120 are mixedly arranged. By arranging in this way, the length of the array antenna 100 in the vertical direction can be shortened as compared with the case where each is arranged separately.

The conductor 130 is disposed on the side of the high frequency band dipole element 120 where the low frequency band dipole element 110 is not disposed. That is, the high frequency band dipole element 120 is sandwiched between the low frequency band dipole element 110 and the conductor 130.
As described above, in the array antenna 100, the low frequency band dipole element 110, the high frequency band dipole element 120, the conductor 130, the high frequency band dipole element 120, and the low frequency band dipole element 110 are arranged in the vertical direction. Arranged to repeat.

That is, two high frequency band dipole elements 120 are sandwiched between two adjacent low frequency band dipole elements 110. When viewed from the high-frequency band dipole element 120, the low-frequency band dipole element 110 is disposed on one side in the vertical direction, but the low-frequency band dipole element 110 is not disposed on the other side. That is, they are asymmetrical above and below the high frequency band dipole element 120. A conductor 130 is provided on the side of the high frequency band dipole element 120 where the low frequency band dipole element 110 is not provided.
Note that the interval between the high frequency band dipole element 120 and the low frequency band dipole element 110 may be different for each location.
Three or more high-frequency band dipole elements 120 may be sandwiched between two adjacent low-frequency band dipole elements 110. In this case, if the high frequency band dipole element 120 is not provided above and below the high frequency band dipole element 120 in the vertical direction, the conductor 130 may be provided for both.

In FIG. 2, a conductor 130-1 and a conductor 130-4 are provided at the upper and lower ends in the vertical direction of the reflector 200. That is, in the repetition of the arrangement of the low-frequency band dipole element 110, the high-frequency band dipole element 120, the conductor 130, the high-frequency band dipole element 120, and the low-frequency band dipole element 110, the conductor 130 The array is cut to remain at the lower end.
The low frequency band dipole element 110 may be cut so as to remain at the upper end and the lower end. Alternatively, the low frequency band dipole element 110 may be cut off so as to remain on one of the upper end and the lower end, and the conductor 130 may remain on the other of the upper end and the lower end.
However, as will be described later, in order to suppress the occurrence of side lobes in directivity, it is preferable that the high-frequency band dipole element 120 does not remain at either the upper end or the lower end.

The numbers of the low-frequency band dipole element 110, the high-frequency band dipole element 120, and the conductors 130 are not limited to the above values.

The radome 500 has, for example, a cylindrical shape, and includes a wall portion 501, a lid portion 502, and a bottom portion 503. The array antenna 100 is housed inside the wall portion 501, the lid portion 502, and the bottom portion 503.

Since the sector antenna 10 includes a low-frequency band dipole element 110 that transmits and receives low-frequency horizontal polarization and a high-frequency band dipole element 120 that transmits and receives high-frequency horizontal polarization, the sector antenna 10 is frequency shared. . The terms “low frequency” and “high frequency” are used to distinguish two types of antenna elements.

<Array antenna 100>
FIG. 3 is a plan view of the array antenna 100 in the sector antenna 10 to which the first embodiment is applied as viewed from the direction perpendicular to the reflector 200 and a sectional view in the direction perpendicular to the reflector 200. 3A is a plan view, and FIG. 3B is a cross-sectional view taken along line IIIb-IIIb in FIG. 3A.
The low-frequency band dipole element 110 has a length W _L , the high-frequency band dipole element 120 has a length W _H , and the conductor 130 has a length W _C.
The distance D _L from the reflection plate 200 in a low frequency band dipole element 110 described above, until the normal direction of the center of the low frequency band dipole element 110 from the surface of the reflecting plate 200 in the vertical line dropped to the reflection plate 200 Length. Similarly, the above-described distance _DH of the high-frequency band dipole element 120 from the reflection plate 200 is from the surface of the reflection plate 200 to the center of the vertical direction of the high-frequency band dipole element 120 in the vertical line standing on the reflection plate 200. Is the length of More Similarly, the distance D _C from the reflection plate 200 of the conductor 130 described above, the length from the surface of the reflecting plate 200 in the vertical line dropped to the reflection plate 200 to the normal direction of the center conductor 130.

Here, the wavelength lambda _L in a free space of the low-frequency _band, in the case of the wavelength lambda _H in a free space of the high-frequency band, an example of numerical values the parameters such as the length W _L of the dipole elements 110 for the low frequency band .
Low-frequency-band dipole element 110 has a length _{W L} about 0.45Ramuda _L, the distance _{D L} from the reflecting plate 200 is approximately 0.2? _L.
The high frequency band dipole element 120 has a length _WH of about 0.45λ _H and a distance _DH from the reflector 200 of about 0.25λ _H. The interval P _H between the high frequency band dipole elements 120 is about 0.75λ _H.
Therefore, the interval P _L between the low-frequency band dipole elements 110 is about 1.5λ _H in the case of 2 × interval P _H.
Then, the conductor 130 has a length _{W C} of about 0.55Ramuda _H, the distance _{D C} from the reflection plate 200 is about 0.25 [lambda _H.
Here, a distance _{D H} from the reflecting plate 200 of the high frequency band dipole element 120, and the distance _{D C} from the reflection plate 200 of the conductor 130 are set to be equal to each other. Incidentally, the distance D _H and the distance D _C may be different.
Note that the above parameters may be set to other numerical values.

2 and 3, the horizontal polarization and the arrangement direction of the low-frequency band dipole element 110, the high-frequency band dipole element 120, and the conductor 130 are orthogonal to each other.

FIG. 4 shows vertical planes of two high-frequency band dipole elements 120 sandwiched between two low-frequency band dipole elements 110 in the array antenna 100 to which the first embodiment is applied. It is a figure which shows internal directivity. 4A shows the directivity of the high-frequency band dipole element 120 arranged on the upper side in the vertical direction, and FIG. 4B shows the directivity of the high-frequency band dipole element 120 arranged on the lower side in the vertical direction. Show directivity. In this specification, in the directivity graph, the vertical direction is set to 0 °, and the direction in which the low-frequency band dipole element 110, the high-frequency band dipole element 120, and the conductor 130 are disposed from the reflector 200 is 90 °. °.

The vertical in-plane directivity of the high frequency band dipole element 120 shown in FIG. 4 will be described with reference to FIGS. Two high-frequency band dipole elements 120 sandwiched between two low-frequency band dipole elements 110 are, for example, a low-frequency band dipole element 110-1 and a low-frequency band dipole element 110-2. A high-frequency band dipole element 120-2 and a high-frequency band dipole element 120-3. The high frequency band dipole element 120-3 is disposed on the upper side in the vertical direction, and the high frequency band dipole element 120-2 is disposed on the lower side in the vertical direction. The dipole element 120 for use.

As shown in FIGS. 4A and 4B, the directivity of the high-frequency band dipole element 120 (for example, the high-frequency band dipole element 120-3) arranged on the upper side in the vertical direction and the lower side in the vertical direction. The difference in directivity of the arranged high frequency band dipole element 120 (for example, the high frequency band dipole element 120-2) is that of the array antenna 100 to which the first embodiment shown in FIG. It is smaller than the high-frequency band dipole element 120.
As will be described later, a conductor 130 (for example, conductor 130-2) is provided between two high frequency band dipole elements 120 (for example, high frequency band dipole elements 120-2 and 120-3). It depends on.

FIG. 5 shows the vertical in-plane directivity in the horizontal polarization in the high frequency band and the vertical in-plane directivity in the horizontal polarization in the low frequency band in the array antenna 100 to which the first embodiment is applied. FIG. 5A shows the vertical in-plane directivity in the horizontal polarization in the high frequency band, and FIG. 5B shows the vertical in-plane directivity in the horizontal polarization in the low frequency band.
The vertical in-plane directivity in the horizontal polarization in the high frequency band shown in FIG. 5A is a directivity obtained by synthesizing 12 high frequency band dipole elements 120 shown in FIGS. 4A and 4B. It is.

As shown in FIGS. 5A and 5B, the vertical in-plane directivity in the horizontal polarization in the high frequency band and the vertical in-plane directivity in the horizontal polarization in the low frequency band are both sharp in the 90 ° direction. Has a peak.
In particular, the vertical in-plane directivity in the horizontal polarization in the high frequency band shown in FIG. 5A is compared with the array antenna 100 to which the first embodiment shown in FIG. 9A described later is not applied. Side lobes are kept small.

FIG. 6 is a perspective view showing an example of the sector antenna 10 to which the first embodiment is not applied. The sector antenna 10 to which the first embodiment shown in FIG. 6 is not applied does not include the conductor 130 in the array antenna 100 of the sector antenna 10 to which the first embodiment shown in FIG. 2 is applied. Since the other configuration is the same as that of the sector antenna 10 to which the first embodiment shown in FIG. 2 is applied, the same reference numerals are given and description thereof is omitted.

FIG. 7 is a plan view of the array antenna 100 in the sector antenna 10 to which the first embodiment is not applied as viewed from the normal direction of the reflection plate 200 and a cross-sectional view of the reflection plate 200 in the normal direction. FIG. 7A shows a plan view, and FIG. 7B shows a cross-sectional view taken along the line VIIb-VIIb.
The array antenna 100 to which the first embodiment shown in FIG. 7 is not applied does not include the conductor 130 in the array antenna 100 to which the first embodiment shown in FIG. 3 is applied. Other configurations are the same as those of the array antenna 100 to which the first embodiment shown in FIG. 3 is applied, and thus the same reference numerals are given and description thereof is omitted.

FIG. 8 shows in the vertical plane of each of the two high-frequency band dipole elements 120 sandwiched between the two low-frequency band dipole elements 110 in the array antenna 100 to which the first embodiment is not applied. It is a figure which shows directivity. FIG. 8A shows the directivity of the high frequency band dipole element 120 arranged on the upper side in the vertical direction, and FIG. 8B shows the directivity of the high frequency band dipole element 120 arranged on the lower side in the vertical direction. Show directivity.

The vertical in-plane directivity of the high frequency band dipole element 120 shown in FIG. 8 will be described with reference to FIGS. Two high-frequency band dipole elements 120 sandwiched between two low-frequency band dipole elements 110 are, for example, a low-frequency band dipole element 110-1 and a low-frequency band dipole element 110-2. A high-frequency band dipole element 120-2 and a high-frequency band dipole element 120-3. The high frequency band dipole element 120-3 is disposed on the upper side in the vertical direction, and the high frequency band dipole element 120-2 is disposed on the lower side in the vertical direction. The dipole element 120 for use.

As shown in FIGS. 8A and 8B, the directivity of the high frequency band dipole element 120 (for example, the high frequency band dipole element 120-3) arranged on the upper side in the vertical direction and the lower side in the vertical direction. There is a difference in the directivity of the high-frequency band dipole element 120 (for example, the high-frequency band dipole element 120-2).
That is, the high frequency band dipole element 120 arranged on the upper side in the vertical direction shown in FIG. 8A shows directivity having a peak in the 135 ° direction.
On the other hand, the high-frequency band dipole element 120 arranged on the lower side in the vertical direction shown in FIG. 8B shows directivity having a peak in the 45 ° direction.
These directivities are different from the directivities of the high-frequency band dipole elements 120 in the array antenna 100 to which the first embodiment is applied as shown in FIG.

FIG. 9 is a diagram illustrating the vertical in-plane directivity in the high-frequency band horizontal polarization and the vertical in-plane directivity in the low-frequency band horizontal polarization in the array antenna 100 to which the first embodiment is not applied. is there. FIG. 9A shows the vertical in-plane directivity in the horizontal polarization in the high frequency band, and FIG. 9B shows the vertical in-plane directivity in the horizontal polarization in the low frequency band.
The vertical in-plane directivity in the horizontal polarization in the high frequency band shown in FIG. 9A is a directivity obtained by synthesizing 12 high frequency band dipole elements 120 shown in FIGS. 8A and 8B. It is.

As shown in FIG. 9A, the horizontal polarization of the high frequency band has a strong peak in the 90 ° direction in the vertical plane, but large side lobes are generated in the 50 ° and 130 ° directions. . This is because the two high frequency band dipole elements 120 shown in FIGS. 8A and 8B have peaks in the 45 ° direction and the 135 ° direction. This directivity is different from the vertical in-plane directivity in the high frequency band horizontal polarization in the array antenna 100 to which the first embodiment shown in FIG. 5A is applied.
On the other hand, the vertical in-plane directivity in the horizontal polarization in the low frequency band shown in FIG. 9B is the low frequency band in the array antenna 100 to which the first embodiment shown in FIG. 5B is applied. There is little difference with the directivity in the vertical plane in horizontal polarization.

Next, a description will be given of factors in which directivity differs between the array antenna 100 to which the first embodiment is applied and the array antenna 100 to which the first embodiment is not applied in the horizontal polarization of the high frequency band.
FIG. 10 is a diagram showing factors that cause differences in vertical in-plane directivity in horizontal polarization in a high frequency band between the array antenna 100 to which the first embodiment is applied and the array antenna 100 to which the first embodiment is not applied. It is a figure explaining. FIG. 10A shows the array antenna 100 to which the first embodiment is applied, and FIG. 10B shows the array antenna 100 to which the first embodiment is not applied.
FIGS. 10A and 10B are both cross-sectional views, and FIG. 10A shows a low-frequency band dipole element 110-1 and a low-frequency band dipole element 110-2 in FIG. 10 (b) shows a range sandwiched between the low-frequency band dipole element 110-1 and the low-frequency band dipole element 110-2 in FIG. 7 (b).

In the array antenna 100 to which the first embodiment shown in FIG. 10A is applied, for example, a part α of the radio wave emitted from the high frequency band dipole element 120-2 is a low frequency band dipole element. After being reflected by 110-1, it goes to the side far from the reflector 200. The other part β of the radio wave emitted from the high frequency band dipole element 120-2 is reflected by the conductor 130-2 and then travels away from the reflector 200.
In the array antenna 100 to which the first embodiment is applied, the low frequency band dipole element 110-1 and the position close to the target are symmetrical to the high frequency band dipole element 120-2. A conductor 130-2 is provided. As a result, the directivity of the radio wave emitted from the high frequency band dipole element 120-2 becomes close to vertical symmetry in the vertical plane as shown in FIG. 4B.
The same applies to the high-frequency band dipole element 120-3.

On the other hand, in the array antenna 100 to which the first embodiment shown in FIG. 10B is not applied, for example, a part α of the radio wave emitted from the high frequency band dipole element 120-2 is low frequency. After being reflected by the band dipole element 110-1, it travels away from the reflector 200. However, the other part β of the radio wave emitted from the high frequency band dipole element 120-2 is not provided with the conductor 130-2, and goes straight as it is and travels away from the reflector 200.
In the array antenna 100 to which the first embodiment is not applied, the directivity of the radio wave emitted from the high-frequency band dipole element 120-2 is symmetrical in the vertical plane as shown in FIG. 8B. do not become.
The same applies to the high-frequency band dipole element 120-3.

As described above, in the array antenna 100 to which the first embodiment is applied, between the two high frequency band dipole elements 120 sandwiched between the two low frequency band dipole elements 110. Similarly to the low-frequency band dipole element 110, by providing the conductor 130 having a function of reflecting the radio wave emitted from the high-frequency band dipole element 120, the vertical in-plane directivity is vertically symmetrical in the vertical direction. It is trying to become.
This suppresses the occurrence of side lobes in the vertical in-plane directivity in the horizontal polarization of the array antenna 100 in the high frequency band.

Therefore, the distance D _C from the reflection plate 200 of the conductor 130, the vertical plane directivity of horizontal polarization of the high frequency band of the array antenna 100, may be a position where it is possible to suppress the side lobes occur.
In the above, the distance _{D C} from the reflection plate 200 of the conductor 130, the reflecting plate 200 of the distance _D is the same as the as _H, a low frequency band dipole element 110 from the reflective plate 200 of the high frequency band dipole element 120 The distance D _L may be the same as the distance D _L , or between the distance D _H and the distance D _L. Furthermore, better even smaller than the distance _{D H,} may even larger than the distance _{D L.}

[Second Embodiment]
In the first embodiment, the sector antenna 10 (array antenna 100) is configured to share frequencies for transmitting and receiving horizontal polarization in the low frequency band and the high frequency band.
In the second embodiment, the sector antenna 10 (array antenna 100) is frequency sharing and polarization sharing for transmitting and receiving horizontal polarization and vertical polarization in the low frequency band and the high frequency band.
Hereinafter, the sector antenna 10 and the array antenna 100 different from the first embodiment will be described.

<Sector antenna 10>
FIG. 11 is a perspective view showing an example of the sector antenna 10 to which the second embodiment is applied.
The array antenna 100 is different from the sector antenna 10 to which the first embodiment shown in FIG. 2 is applied. Hereinafter, different parts will be described, and the same parts are denoted by the same reference numerals, and the description thereof will be omitted.

The array antenna 100 in the sector antenna 10 to which the second embodiment is applied is for a low frequency band that transmits and receives horizontal polarization, which is included in the sector antenna 10 to which the first embodiment shown in FIG. 2 is applied. In addition to dipole elements 110-1 to 110-3, high frequency band dipole elements 120-1 to 120-6, and conductors 130-1 to 130-4, as an example of a third antenna element that transmits and receives vertically polarized waves Low-frequency band dipole elements 111-1 to 111-3, low-frequency band dipole elements 112-1 to 112-3, and high-frequency band dipole elements 121-1 to 121-6 as an example of a fourth antenna element It has. If the low frequency band dipole elements 111-1 to 111-3 are not distinguished from each other, the low frequency band dipole elements 111 and the low frequency band dipole elements 112-1 to 112-3 are not distinguished from each other. When the frequency band dipole element 112 and the high frequency band dipole elements 121-1 to 121-6 are not distinguished from each other, they are referred to as a high frequency band dipole element 121.

The low-frequency band dipole element 111 and the low-frequency band dipole element 112 each include a pair of element portions arranged in the vertical direction, and one end portion in the horizontal direction of the low-frequency band dipole element 110. It is provided at the other end. For example, the low frequency band dipole element 111-1 and the low frequency band dipole element 112-1 are provided at one end and the other end of the low frequency band dipole element 110-1.
On the other hand, the high-frequency band dipole element 121 includes a pair of element portions arranged side by side in the vertical direction, and is combined with the high-frequency band dipole element 120 in a cross shape. For example, the high frequency band dipole element 121-1 is provided in combination with the high frequency band dipole element 120-1 in a cross shape.

The low-frequency band dipole element 111, the low-frequency band dipole element 112, and the high-frequency band dipole element 121 are made of a conductive material, like the low-frequency band dipole element 110, the high-frequency band dipole element 120, and the conductor 130. 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. Further, similarly to the low frequency band dipole element 110, the high frequency band dipole element 120, and the conductor 130, the low frequency band dipole element 111, the low frequency band dipole element 112, and the high frequency band dipole element 121 are made of glass. It may be constituted by a metal layer such as Al or Cu provided on a substrate made of a dielectric material such as epoxy.

The sector antenna 10 includes a low-frequency band and high-frequency band horizontally polarized transmission /

reception cables

31 and 32 of the first embodiment, and a low-frequency band and high-frequency band vertically-polarized transmission / reception cable 33. , 34 are provided.
Note that the numbers of the low-frequency band dipole elements 110, 111, and 112, the high-frequency band dipole elements 120 and 121, and the conductors 130 are not limited to the above values.

<Array antenna 100>
FIG. 12 is a plan view of the array antenna 100 in the sector antenna 10 to which the second embodiment is applied as viewed from the perpendicular direction of the reflector 200 and a sectional view of the reflector 200 in the perpendicular direction. 12A shows a plan view, and FIG. 12B shows a cross-sectional view taken along line XIIb-XIIb in FIG. 12A.
Low-frequency-band dipole element 110, the dipole elements 120 for high frequency band, (such as the length W _L of the low frequency band dipole element 110) parameters of the conductor 130 is the same as in the first embodiment.
Then, a low frequency band dipole element 111 low-frequency-band dipole element 112 is a low as well as the frequency band dipole element 110 length W _L, provided from the reflection plate 200 at a distance D _L.
High-frequency-band dipole element 121 is a similarly long W _H dipole element 120 for high-frequency bands, provided from the reflection plate 200 at a distance D _H.

Also in the array antenna 100 according to the second embodiment, the high frequency band dipole elements 120 and 121 are sandwiched between the low frequency band dipole element 110 and the conductor 130 in the vertical direction. Therefore, in the vertical direction, the radio waves emitted by the horizontally polarized waves can be reflected symmetrically.
Thereby, it can suppress that a side lobe generate | occur | produces in the vertical in-plane directivity in the horizontal polarization of the high frequency band of the array antenna 100. FIG.

Here, the polarization is shared in the low frequency band and the high frequency band, but only one of the polarizations may be shared. The distance from the reflection plate 200 in a low frequency band dipole element 111 and the low frequency band dipole element 112 may not necessarily be the same from the reflection plate 200 in a low frequency band dipole element 110 and the distance D _L, the distance D _L and may be a different distance _{D L} '. Similarly, the distance from the reflecting plate 200 of the high frequency band dipole element 121 may not be the same necessarily from the reflecting plate 200 of the high frequency band dipole element 120 and the distance D _H, the distance D _H and different distances D _H It may be '.

[Third Embodiment]
Similar to the sector antenna 10 (array antenna 100) to which the second embodiment is applied, the sector antenna 10 (array antenna 100) to which the third embodiment is applied is vertical in the low frequency band and the high frequency band. Frequency sharing and polarization sharing for transmitting and receiving polarization and horizontal polarization.
The sector antenna 10 to which the third embodiment is applied differs from the sector antenna 10 to which the second embodiment shown in FIG. 11 is applied in the array antenna 100. Hereinafter, different parts will be described, and the same parts are denoted by the same reference numerals, and the description thereof will be omitted.

<Sector antenna 10>
FIG. 13 is a perspective view showing an example of the sector antenna 10 to which the third embodiment is applied.
The array antenna 100 in the sector antenna 10 to which the third embodiment is applied is a low-frequency band dipole element 110-1 to 110-3 that transmits and receives horizontal polarization in the first embodiment shown in FIG. And high frequency band dipole elements 120-1 to 120-6. Unlike the first embodiment, the high frequency band dipole elements 120-1 to 120-6 are shifted in the horizontal direction.
Similarly to the high-frequency band dipole elements 120-1 to 120-6, the second antenna is provided with a pair of element portions arranged in the horizontal direction and arranged in the vertical direction to transmit and receive horizontal polarization. As other examples of the elements, high frequency band dipole elements 122-1 to 122-6 are provided.
The high frequency band dipole elements 120-1 to 120-6 and the high frequency band dipole elements 122-1 to 122-6 are provided with the same subscripts (such as -1) arranged in the horizontal direction.

Then, in order to transmit and receive vertically polarized waves, low frequency band dipole elements 113-1 to 113-3 as another example of the third antenna element, and a high frequency band as another example of the fourth antenna element Dipole elements 121-1 to 121-6 for high frequency and dipole elements 123-1 to 123-6 for high frequency bands.
Furthermore, conductors 131-1 to 131-4 and conductors 132-1 to 132-4 are provided in place of the conductors 130-1 to 130-4 in the first and second embodiments. .
When the low frequency band dipole elements 113-1 to 113-3, the high frequency band dipole elements 122-1 to 122-6, and the high frequency band dipole elements 123-1 to 123-6 are not distinguished from each other, the low frequency band It is expressed as a band dipole element 113, a high frequency band dipole element 122, and a high frequency band dipole element 123. When the conductors 131-1 to 131-4 and the conductors 132-1 to 132-4 are not distinguished from each other, they are referred to as a conductor 131 and a conductor 132, respectively.

The low-frequency band dipole element 113, the high-frequency band dipole element 121, the high-frequency band dipole element 122, the high-frequency band dipole element 123, the conductor 131, and the conductor 132 are the low-frequency band dipole element 110 and the high-frequency band. Similarly to the dipole element 120 for a metal, it may be made of a conductive material, and 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. Further, similarly to the low frequency band dipole element 110 and the high frequency band dipole element 120, the low frequency band dipole element 113, the high frequency band dipole element 121, the high frequency band dipole element 122, and the high frequency band dipole. The element 123, the conductor 131, and the conductor 132 may be configured by a metal layer such as Al or Cu provided on a substrate configured by a dielectric material such as glass epoxy.

The low frequency band dipole element 113 is combined with the low frequency band dipole element 110 in a cross shape. For example, the low-frequency band dipole element 113-1 is provided in combination with the low-frequency band dipole element 110-1 in a cross shape.
Similarly to the second embodiment, the high frequency band dipole element 121 is combined with the high frequency band dipole element 120 in a cross shape. For example, the high frequency band dipole element 121-1 is provided in combination with the high frequency band dipole element 120-1 in a cross shape.
Further, the high frequency band dipole element 123 is provided in combination with the high frequency band dipole element 122 in a cross shape. For example, the high-frequency band dipole element 123-1 is provided in combination with the high-frequency band dipole element 122-1 in a cross shape.

Further, the conductor 131 has an H-shaped planar shape in a plane parallel to the plane including the reflector 200, and is for two high frequency bands provided between two low frequency band dipole elements 110. It is provided between the dipole elements 120. For example, between the high frequency band dipole element 120-2 and the high frequency band dipole element 120-3 provided between the low frequency band dipole element 110-1 and the low frequency band dipole element 110-2. In addition, a conductor 131-2 is provided.
The conductor 132 has an H-shaped planar shape in a plane parallel to the plane including the reflector 200, similar to the conductor 131, and the two high-frequency band dipole elements 110 provided between the two high-frequency bands. It is provided between the frequency band dipole elements 122. For example, between the high frequency band dipole element 122-2 and the high frequency band dipole element 122-3 provided between the low frequency band dipole element 110-1 and the low frequency band dipole element 110-2. In addition, a conductor 132-2 is provided.

reception cables

31 and 32 of the first embodiment, and a low-frequency band and high-frequency band vertically-polarized transmission / reception cable 33. , 34 are provided.
The numbers of the low-frequency band dipole elements 110 and 113, the high-frequency band dipole elements 120, 121, 122, and 123, and the conductors 131 and 132 are not limited to the above values.
Further, the surface including the conductor 131 and the conductor 132 is not necessarily parallel to the reflecting plate 200, and may be a surface that is perpendicular to the reflecting plate 200 or rotated by 45 degrees, for example.
The conductor 131 and the conductor 132 may be formed by bending a rod-shaped conductor into an H shape or a U shape instead of a planar shape. Furthermore, the shape provided with the member in which direction differs from the member which comprises a center part in the edge part may be sufficient. At this time, these members are preferably connected in a direct current manner.

<Array antenna 100>
FIG. 14 is a plan view of the array antenna 100 in the sector antenna 10 to which the third embodiment is applied as viewed from the perpendicular direction of the reflector 200 and a sectional view of the reflector 200 in the perpendicular direction. 14A shows a plan view, and FIG. 14B shows a cross-sectional view taken along line XIVb-XIVb in FIG. 14A.
Low-frequency-band dipole element 110, (such as the length W _L of the low frequency band dipole element 110) parameter of the higher frequency band dipole element 120 is the same as in the first embodiment.
Further, the parameters of the low-frequency band dipole element 113 are the same as those of the low-frequency band dipole element 110, and the parameters of the high-frequency band dipole elements 121, 122, and 123 are the same as those of the high-frequency band dipole element 120. is there.
Then, the conductor 131 and 132 are provided at a distance _{D C} from the reflecting plate 200.

The H-shaped planar shape of the conductors 131 and 132 is to increase the electrical length of the conductors 131 and 132 equivalently. By increasing the length, the conductors 131 and 132 are operated as reflectors, and the balance between the reflection by the low-frequency band dipole element 110 and the reflection by the conductor 131 or the conductor 132 of the radio wave emitted from the high-frequency band dipole element 120. This is to ensure the symmetry of directivity between the upper side and the lower side in the vertical plane. Thereby, in the array antenna 100, the side lobe generated in the vertical in-plane directivity in the horizontal polarization of the high frequency band is suppressed.

As described above, also in the array antenna 100 to which the third embodiment is applied, the high frequency band dipole element 120 used for horizontal polarization transmission / reception has the low frequency band dipole on both sides in the vertical direction. Either the element 110 or the conductor 131 is adjacent. Similarly, the high frequency band dipole element 122 is adjacent to either the low frequency band dipole element 110 or the conductor 132 on both sides in the vertical direction. Therefore, in the array antenna 100, the side lobe generated in the vertical in-plane directivity in the horizontal polarization of the high frequency band is suppressed.

Also in the array antenna 100 according to the third embodiment, the high frequency band dipole element 120 is sandwiched between the low frequency band dipole element 110 and the conductor 131 in the vertical direction. The high frequency band dipole element 122 is sandwiched between the low frequency band dipole element 110 and the conductor 132 in the vertical direction.
Therefore, the level of the side lobe of the vertical in-plane directivity in the horizontal polarization of the high frequency band of the array antenna 100 can be suppressed.

Here, the polarization is shared in the low frequency band and the high frequency band, but only one of the polarizations may be shared.
The planar shape of the conductor 130 in the first embodiment and the second embodiment may be an H shape or a U shape.

In the first to third embodiments, the conductors 130, 131, and 132 are conductors made of a conductive material. However, any conductor having a function of reflecting radio waves may be used. Carbon materials having lower electrical conductivity can be used.

In the first to third embodiments, the reflector 200 is a flat plate, but the both ends in the horizontal direction are a low-frequency band dipole element 110 and a high-frequency band dipole element 120. Or may be bent on the side opposite to the side on which the high-frequency band dipole element 120 or the like is provided.
Furthermore, the conductor 130 in the first and second embodiments and the conductors 131 and 132 in the third embodiment are parasitic and are not connected to either. The reflector 200 may be electrically connected.

Further, the low-frequency band dipole element 110, the high-frequency band dipole element 120 according to the first embodiment, the low-frequency band dipole elements 110, 111, and 112 according to the second embodiment, and the high-frequency band dipole element. 120, 121, a part of or all of the low frequency band dipole elements 110, 113 and the high frequency band dipole elements 120, 121, 122, 123 of the third embodiment, and a voltage constant on the side far from the reflector 200. A parasitic element for adjusting characteristics such as a standing wave ratio (VSWR) and directivity may be provided.

In the second embodiment and the third embodiment, vertical polarization and horizontal polarization are transmitted and received.
However, in the second embodiment, the low-frequency band dipole elements 110, 111, and 112 having the same subscript (−1 or the like) are rotated by 45 ° at the center of the low-frequency band dipole element 110, and A pair of high-frequency band dipole elements 120 and 121 having the same subscript (−1, etc.) is paired and rotated by 45 ° at the center of the high-frequency band dipole elements 120 and 121 to transmit and receive ± 45 ° polarized waves. be able to.
At this time, the array antenna 100 transmits / receives ± 45 ° polarization instead of vertical polarization and horizontal polarization. Therefore, “vertical” and “horizontal” may be read as “45 °” and “−45 °”. The same applies to polarized waves of other angles.

The present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Base station antenna, 2 ... Cell, 3-1, 3-1 to 3-3 ... Sector, 10, 10-1 to 10-3 ... Sector antenna, 11 ... Main lobe, 20 ... Steel tower, 31, 32, 33, 34 ... Transmission / reception cable, 100 ... Array antenna, 110, 110-1 to 110-3, 111, 111-1 to 111-3, 112, 112-1 to 112-3, 113, 113-1 to 113-3 ... Dipole element for low frequency band, 120, 120-1 to 120-6, 121, 121-1 to 121-6, 122, 122-1 to 122-6, 123, 123-1 to 123-6 ... high frequency band Dipole element, 130, 130-1 to 130-4, 131, 131-1 to 131-4, 132, 132-1 to 132-4 ... conductor, 200 ... reflector, 500 ... radome

Claims

A reflector made of a conductive material;
A plurality of first antennas arranged in a direction intersecting with a predetermined polarization direction at a predetermined first distance from the reflecting plate and transmitting / receiving radio waves of the polarization in the first frequency band Elements,
The polarization of the second frequency band higher than the first frequency band is arranged at a predetermined second distance from the reflector in a mixed manner with the plurality of first antenna elements in the direction. A plurality of second antenna elements for transmitting and receiving radio waves;
Among the plurality of second antenna elements, the second antenna element is disposed between the two second antenna elements adjacent in the direction when none of the plurality of first antenna elements is disposed. An array antenna comprising a member that reflects radio waves transmitted and received by an antenna element.
The member that reflects the radio wave is a conductor made of a conductive material having a longitudinal direction in the polarization direction, and is provided at a predetermined third distance from the reflector. The array antenna according to claim 1.
The array antenna according to claim 2, wherein the conductor includes a member having a different direction from a member constituting the central portion at an end portion, and each member is connected in a direct current manner.
The array antenna according to claim 1, further comprising a third antenna element that transmits and receives a radio wave having a polarization orthogonal to the polarization in the first frequency band.
The array antenna according to claim 1 or 2, further comprising a fourth antenna element that transmits and receives a radio wave having a polarization orthogonal to the polarization in the second frequency band.
A reflection plate made of a conductive material, and arranged in a direction intersecting a predetermined polarization direction at a predetermined first distance from the reflection plate, and the polarization of the polarization in the first frequency band A plurality of first antenna elements for transmitting and receiving radio waves and a predetermined second distance from the reflector, and arranged in a mixed manner with the plurality of first antenna elements in the direction, the first frequency A plurality of second antenna elements for transmitting and receiving radio waves of the polarization in a second frequency band higher than the band, and two second antenna elements adjacent in the direction among the plurality of second antenna elements An array antenna comprising a member that reflects a radio wave transmitted and received by the second antenna element, which is disposed when none of the plurality of first antenna elements is disposed between,
A sector antenna comprising a radome that houses the array antenna.