JP4905239B2 - Antenna device - Google Patents

Description

  The present invention relates to an antenna device, and more particularly to a polarization sharing antenna device used for mobile communication base stations such as mobile phones and PHS.

In mobile communication base station antennas, space diversity and polarization diversity are often used to suppress multipath fading. Spatial diversity requires two antennas to be spaced apart by a certain distance, which increases the overall antenna system. On the other hand, since polarization diversity uses two orthogonal polarizations, the size of the entire antenna system can be reduced compared to space diversity, and the equipment can be used effectively.
In the base station, generally, the radio zone configuration is set to 3 sectors or 6 sectors, and the polarization diversity antenna for the base station is required to make the vertical and horizontal polarization beam widths substantially equal in the horizontal plane. Further, the required beam width on the horizontal plane varies depending on the communication method and the number of sectors.
Dual-polarized antennas include cross-polarized patch antennas and antennas that combine orthogonal dipoles. However, patch antennas have the disadvantage that their reflection characteristics are narrower than that of dipole antennas, requiring wideband characteristics. In many cases, antennas combined with orthogonal dipoles are used.
Japanese Patent No. 2846609 and Japanese Patent No. 3625142 are conventional examples of antennas that combine orthogonal dipoles. In Japanese Patent No. 2846609, two vertically polarized dipoles are installed in front of the reflector, and a horizontally polarized dipole is installed so as to cross almost the center in the longitudinal direction of the vertically polarized dipole. The beam widths of vertical polarization and horizontal polarization in the horizontal plane are almost equal. In Japanese Patent No. 3625142, a V-shaped horizontally polarized dipole and two vertically polarized dipoles are installed in front of the reflector so that the vertical and horizontal polarized beam widths in the horizontal plane are 60. I am trying.

Patent No. 2846609 (FIG. 8 etc.) Patent No. 3625142 (FIG. 11 etc.)

In the base station antenna shown in Japanese Patent No. 2846609, since the horizontally polarized dipole is installed so as to cross the vertically polarized dipole, it is possible to increase the bandwidth between the horizontally polarized dipole and the vertically polarized dipole. Therefore, when an unexcited dipole is loaded, the configuration becomes complicated. Therefore, there is a problem that the degree of freedom of the structural parameters that can be adjusted for impedance matching of the horizontally polarized dipole and the vertically polarized dipole is reduced, and the design becomes difficult.
On the other hand, the base station antenna disclosed in Japanese Patent No. 3625142 shows a case where the V-shaped horizontally polarized dipole and the two vertically polarized dipoles are shifted in a direction perpendicular to the horizontal plane. In this way, the degree of freedom of the structural parameters that can be adjusted for impedance matching of the horizontally polarized dipole and the vertically polarized dipole is not reduced, and the design is facilitated. However, when the horizontally polarized dipole and the vertically polarized dipole are arranged to be shifted in the vertical direction, there is a problem that mutual coupling between the horizontally polarized dipole and the vertically polarized dipole increases.

  The present invention has been made to solve the above-described problems, and provides a polarization-sharing antenna that is easy to design and has a small mutual coupling between a horizontally polarized dipole and a vertically polarized dipole. For the purpose.

In the antenna device according to the present invention, the first vertical polarization dipole and the second vertical polarization dipole are arranged substantially in parallel and in the same direction, and the first vertical polarization dipole and The lengths of the first feed line and the second feed line connected to the feed part of the second vertically polarized dipole are set to an electrical length that is an odd multiple of a quarter wavelength at the substantially center frequency of the used frequency band. Thus, the mutual coupling between the horizontally polarized dipole and the vertically polarized dipole is reduced.
In other words, an antenna device according to the present invention is provided with a reflector and an approximately half-wavelength electric power at approximately the center frequency that is provided in front of the reflector and substantially parallel to the reflector and resonates at approximately the center frequency of the used frequency band. A long first vertical polarization dipole, a second vertical polarization dipole and a horizontal polarization dipole, and a feed line to the first vertical polarization dipole and the second vertical polarization dipole The first vertically polarized dipole and the second vertically polarized dipole are arranged in substantially the same direction and in parallel, and the horizontally polarized dipole includes the first vertically polarized dipole and The second vertical polarization dipole is arranged so as to be orthogonal to the second dipole for vertical polarization so as not to overlap with each other, the feed line is branched and extends, and each of the feed portions of the first vertical polarization dipole The first feed line and the second feed line whose electrical length connected to the feed part of the second vertically polarized dipole is an odd multiple of ¼ wavelength at substantially the center frequency of the used frequency band. It is characterized by having.

  In the present invention, as described above, the first vertically polarized dipole and the second vertically polarized dipole are arranged in substantially the same direction in the same direction, and the horizontally polarized dipole is used for the first vertically polarized dipole. The dipole and the second vertically polarized dipole are arranged so as to be orthogonal and shifted so as not to overlap with each other, and respectively to the feed portion of the first vertically polarized dipole and the feed portion of the second vertically polarized dipole. Since the length of the first feed line and the second feed line to be connected is set to an electrical length that is an odd multiple of a quarter wavelength at substantially the center frequency of the used frequency band, the design is easy and the horizontal polarization There is an effect that a dual-polarized antenna having a small mutual coupling between the dipole for vertical polarization and the dipole for vertical polarization is obtained.

Embodiment 1 FIG.
An antenna device according to Embodiment 1 of the present invention will be described with reference to FIGS.
FIG. 1 is a perspective view for explaining an antenna apparatus according to Embodiment 1 of the present invention. 2A is a front view of the antenna device according to Embodiment 1 of the present invention shown in FIG. 1, and FIG. 2B is a side view. 3 is a perspective view of the antenna device showing the case where the strip conductors 9, 10, and 11 are installed on the back surface of the reflecting plate 20 in the antenna device shown in FIG.
In addition, in each figure, the same code | symbol shows the same or equivalent part.

Next, details of the configuration will be described.
Let f _{0 be} the center frequency of the desired frequency band. In FIG. 1, the reflecting plate 20 is a rectangular conductor plate, and two sides are substantially perpendicular to the horizontal plane. The vertically polarized dipole 1, the vertically polarized dipole 2, and the horizontally polarized dipole 12 are substantially parallel to the reflector 20 with a length of 1/8 to ¼ wavelength at f ₀ from the reflector 20. Is arranged. The vertically polarized dipole 1 and the vertically polarized dipole 2 are in the same direction and the extending direction thereof is substantially perpendicular to the horizontal plane, and the horizontally polarized dipole 12 faces the vertically polarized dipole 1 and the vertically polarized dipole 2. The central power feeding part is arranged on a symmetrical symmetry plane, and the extending direction is substantially parallel to the horizontal plane.
Here, in the dipole antenna with a reflector, when the distance between the dipole and the reflector is changed from ¼ wavelength to ½ wavelength, the maximum gain direction is the front direction of the antenna (direction perpendicular to the reflector). It will deviate from. Therefore, normally, the distance between the dipole and the reflector is set to ¼ wavelength or less. Further, when the distance between the dipole and the reflection plate is decreased from the quarter wavelength, the reflection characteristic becomes narrower. That is, the distance between the dipole and the reflection plate can be made smaller than a quarter wavelength as long as the reflection characteristics are good in a desired band. For the reasons described above, wherein the vertical polarized wave dipole 1, vertically polarized dipole 2, a horizontally polarized dipole 12, 1 / 8-1 / 4 wavelength distances in f ₀ of the reflection plate 20 It is said.

The vertically polarized dipole 1 and the vertically polarized dipole 2 are arranged at an appropriate interval in a direction parallel to the horizontal plane. In addition, the vertically polarized dipoles 1 and 2 and the horizontally polarized dipole 12 do not overlap each other and are shifted in the vertical direction. Furthermore, vertically polarized dipole 1, vertically polarized dipole 2, dipole for horizontal polarization 12, an electrical length of about a half wavelength at f _0, and the length which resonates at f _0.

  The horizontally polarized dipole 12 is fed by a feeding unit 13. One end of the feeding portion 3 of the vertically polarized dipole 1 is connected to the conductor plate 5 and the other end is connected to the conductor plate 6. The conductor plate 5 and the conductor plate 6 constitute a first taper balun. Similarly, the feeding section 4 of the vertically polarized dipole 2 has one end connected to the conductor plate 7 and the other end connected to the conductor plate 8, and the conductor plate 7 and the conductor plate 8 constitute a second taper balun. ing.

  Wide end portions of the conductive plate 6 and the conductive plate 8 of the taper balun are connected to the reflection plate 20. The other end of the conductor plate 5 of the taper balun is connected to the strip conductor 9, and the other end of the conductor plate 7 is connected to the strip conductor 10. The strip conductor 9 forms a first strip line using the reflector 20 as a ground conductor. Further, the strip conductor 10 constitutes a second strip line using the reflector 20 as a ground conductor.

The strip conductor 11 constitutes a third strip line using the reflector 20 as a ground conductor. The strip conductor 11 is connected to the strip conductor 9 and the strip conductor 10 via a T branch.
Here, if the balanced transmission system and the unbalanced transmission system are directly connected, the original transmission state of both is disturbed, and unexpected transmission occurs. Therefore, a balun (balance-unbalance conversion circuit) is used when power is supplied to a balanced dipole antenna using a strip line of an unbalanced transmission system. In the antenna apparatus shown in FIG. 1, dipoles, baluns, and strip conductors (that is, vertically polarized dipoles 1 and 2, conductor plates 5 and 7, strip conductors 9, 10, and 11) are formed from a single sheet metal. Thus, since the manufacturing can be facilitated, a taper balun is adopted as an example. There are various types of baluns, and the baluns are not limited to tapered baluns.

Here, as shown in FIG. 2A, the length from the T-shaped branch portion of the first strip line (strip conductor 9) to the connection portion with the first taper balun (conductor plate 5) is set as follows. The length from the T-shaped branch portion of the second strip line (strip conductor 10) to the connection portion with the second taper balun (conductor plate 7) is also L1. Further, as shown in FIG. 2B, the length of the conductor plates 5 and 7 of the taper balun is L2. In this, (L1 + L2), the electrical length of _{f 0} is from about (1/4 + n / 2 ) wavelength. Here, n is an integer of 0 or more.

Next, the operation will be described.
First, consider the case of vertical polarization excitation. The signal injected into the third strip line (strip conductor 11) is distributed to the first strip line (strip conductor 9) and the second strip line (strip conductor 10) through the branch part.

  The two distributed signals are converted from the unbalanced mode to the balanced mode by the first taper balun (conductor plates 5 and 6) and the second taper balun (conductor plates 7 and 8), and are vertically deviated by the power feeding unit 3. The wave dipole 1 is excited by the feed unit 4 and the vertically polarized dipole 2 is excited. Further, since the distance from the branch part of the strip line to the vertically polarized dipoles 1 and 2 is the same (L1 + L2), the vertically polarized dipoles 1 and 2 are excited in the same phase.

  By changing the distance between the two vertically polarized dipoles 1 and 2, the beam width of the vertically polarized wave in the horizontal plane can be adjusted. Further, the coupling between the vertically polarized dipole 1 and the horizontally polarized dipole 12 and the coupling between the vertically polarized dipole 2 and the horizontally polarized dipole 12 have substantially the same amplitude and are almost in reverse phase. Offset. Therefore, when considered as a whole, the coupling between the vertically polarized dipoles 1 and 2 and the horizontally polarized dipole 12 becomes small during vertical polarization excitation.

  Next, consider the time of horizontal polarization excitation. The horizontally polarized dipole 12 is excited by the power feeding unit 13. At this time, as described above, the coupling between the horizontally polarized dipole 12 and the vertically polarized dipole 1 and the coupling between the horizontally polarized dipole 12 and the vertically polarized dipole 2 have substantially the same amplitude and are substantially opposite. Become a phase. The signal coupled to the vertically polarized dipole 1 passes through the first taper balun (conductor plates 5 and 6) and the first strip line (strip conductor 9) and reaches the branching portion. Similarly, the signal coupled to the vertically polarized dipole 2 passes through the second taper balun (conductor plates 7 and 8) and the second strip line (strip conductor 10) and reaches the branching portion. At this time, since the two signals that have arrived at the branching portion have opposite phases, the power at the branching portion is approximately zero. Further, the amplitude of the electric power propagated toward the third strip line (strip conductor 11) becomes very small.

  Thus, since the amplitude of the electric power propagated toward the third strip line is very small and the electric power at the branching portion is about 0, the strip conductor 9 and the strip conductor 10 are It can be regarded as equivalent to short-circuiting with the reflecting plate 20 at the branch portion.

  The transmission line with the short end has an infinite impedance when the electrical length from the short end is (1/4 + n / 2) wavelength, and the electrical length from the short end is (n / 2) wavelength. In this case, the impedance becomes 0 (n is an integer of 0 or more).

Here, in the antenna device according to the first embodiment, the electrical length at f ₀ of the distance (L1 + L2) from the branch part of the strip line to the vertically polarized dipoles 1 and 2 is about (1/4 + n / 2). The wavelength. Therefore, in the feeding parts 3 and 4 of the vertically polarized dipoles 1 and 2, the impedance becomes very large, and the coupling from the horizontally polarized dipole 12 to the vertically polarized dipoles 1 and 2 becomes very small.

If the electrical length at f ₀ of (L1 + L2) is about (n / 2) wavelength, the impedance at the feeding parts 3 and 4 of the vertical polarization dipoles 1 and 2 becomes very small, and the horizontal polarization is used. The coupling from the dipole 12 to the vertically polarized dipoles 1 and 2 is increased. As a result, there arises a problem that the level of cross polarization increases and impedance matching of the horizontally polarized dipole 12 becomes difficult.
Therefore, it is very effective to set the electrical length at f ₀ of the distance (L1 + L2) shown in the present invention to be about (1/4 + n / 2) wavelength (where n is an integer of 0 or more).

In the antenna device illustrated in FIGS. 1 and 2, the strip conductors 9, 10, and 11 are installed on the side where the dipole of the reflecting plate 20 is provided. However, as shown in FIG. The holes 30 and 31 smaller than the wavelength at f ₀ so that the influence of the above is not a problem are formed, and the conductor plates 5 and 7 are extended through the holes 30 and 31 to the side where the reflector 20 does not have a dipole. You may make it the structure which installs 10 and 11 in the side without the dipole of the reflecting plate 20. FIG.

  In the first embodiment, the feeding method of the horizontally polarized dipole 12 is not limited. For example, as with the vertically polarized dipoles 1 and 2, a taper balun is formed from the strip line on the reflector 20. It is conceivable to supply power through the cable. Further, a method of supplying power by parallel two wires is also conceivable.

In order to achieve impedance matching, the width of the strip conductor 9, strip conductor 10, and strip conductor 11 may be changed in the middle. For example, after distributing from the third strip line to the first and second strip lines, an impedance converter having an electrical length of ¼ wavelength at f ₀ may be formed on the first and second strip lines. Conceivable.

  Further, in order to achieve impedance matching with the vertically polarized dipoles 1 and 2, an open stub and a short stub are provided in the first, second and third strips in the middle of the first, second and third strip lines. You may install in parallel with a track.

As described above, in the antenna device according to the present invention, the horizontal polarization dipole and the two vertical polarization dipoles are installed in front of the reflector so as not to overlap each other, and the branch portion of the feed line of the vertical polarization dipole By making the electrical length at f ₀ from the power supply part of the dipole to about (1/4 + n / 2) wavelength (where n is an integer of 0 or more), the beam widths of the vertical polarization and horizontal polarization in the horizontal plane are This has the effect of providing a dual-polarized antenna that is substantially equal, easy to design, and has a small mutual coupling between the horizontally polarized dipole and the vertically polarized dipole.

Embodiment 2. FIG.
4 is a perspective view for explaining an antenna device according to Embodiment 2 of the present invention. In the second embodiment, in the antenna device having the configuration shown in the first embodiment, non-excited dipoles 14, 15, and 16 are provided in the vicinity of the vertically polarized dipoles 1 and 2 and the horizontally polarized dipole 12, respectively. This is an antenna device having an installed configuration.

Next, details of the configuration will be described.
Let f _h be the upper limit frequency of the desired frequency band. In FIG. 4, an unexcited dipole 14 is installed in the vicinity of the vertically polarized dipole 1, an unexcited dipole 15 is installed in the vicinity of the vertically polarized dipole 2, and an unexcited dipole in the vicinity of the horizontally polarized dipole 12. 16 is installed. Further, parasitic dipoles 14 and 15 are the same direction as the vertically polarized wave dipole 1,2 substantially perpendicular to its extension direction is a horizontal plane, an electrical length of about a half wavelength at f _h, length resonant at f _h Say it. Further, parasitic dipole 16 has its elongated direction is the same direction as the horizontally polarized dipole 12 is substantially parallel to the horizontal plane, an electrical length of about a half wavelength at f _0, and the length which resonates at f _0.

  As described above, by installing the non-excited dipoles 14, 15, and 16, it is possible to widen the bandwidth of the antenna that can obtain good reflection characteristics.

Further, the electrical length of the non-excited dipoles 14 and 15 is set to about a half wavelength at the upper limit frequency f _h of the desired frequency band, and is shorter than about a half wavelength at the center frequency f _0, so that the horizontally polarized dipole 12 is made. At the time of excited horizontal polarization excitation, the coupling from the horizontally polarized dipole 12 to the non-excited dipoles 14 and 15 can be reduced.

From the above, it is possible to widen the antenna by installing the non-excited dipoles 14, 15 and 16, and the electrical length of the non-excited dipoles 14 and 15 is about half a wavelength at f _h , so There is an effect that the coupling from the wave dipole 12 to the non-excited dipoles 14 and 15 can be reduced.

Embodiment 3 FIG.
FIG. 5 is a perspective view for explaining an antenna apparatus according to Embodiment 3 of the present invention. The third embodiment is an antenna device having a configuration in which the horizontally polarized dipole 12 and the non-excited dipole 16 are bent in the middle of the antenna device having the configuration shown in the first embodiment or the second embodiment. . 5 exemplifies the case where the horizontal polarization dipole 12 and the non-excitation dipole 16 are bent at two right angles near both ends in the antenna device having the configuration shown in the second embodiment. To do.

  As shown in FIG. 5, the horizontally polarized dipole 12 and the non-excited dipole 16 are bent at right angles at two locations near both ends.

  In this way, by bending the horizontal polarization dipole 12 and the non-excitation dipole 16 in the middle, the length of the orthogonal projection of the horizontal polarization dipole 12 and the non-excitation dipole 16 onto the reflector 20 is shortened, and the antenna opening This is equivalent to an antenna having a small size, and the beam width of horizontal polarization in the horizontal plane can be increased. Further, since the antenna opening size is changed by bending without changing the length of the dipole, the resonance frequency of the dipole does not change.

Although FIG. 5 shows the case where the horizontally polarized dipole 12 and the non-excited dipole 16 are bent at right angles toward the reflector 20 at two points in the middle thereof, the present invention is not limited to this. The length of the orthogonal projection of the wave dipole 12 and the non-excited dipole 16 onto the reflection plate 20 may be shortened and equivalent to an antenna having a small antenna aperture size.
Accordingly, the horizontal polarization dipole 12 and the non-excitation dipole 16 may be bent in one place to have a V shape. Further, the bending angle may not be 90 degrees. It may be curved.

  In the above description, the antenna device having the configuration shown in the second embodiment is described. However, it is needless to say that the antenna device can be similarly applied to the antenna device shown in the first embodiment.

  As described above, by changing the position where the horizontal polarization dipole 12 and the non-excitation dipole 16 are bent, the number of bent portions, the bending angle, and the like, the dipole 12 for horizontal polarization is maintained while maintaining the resonance frequency of the dipole. When excited, it has the effect that the beam width of horizontal polarization in the horizontal plane can be adjusted.

Embodiment 4 FIG.
FIG. 6 is a perspective view for explaining an antenna apparatus according to Embodiment 4 of the present invention. In this fourth embodiment, the vertically polarized dipoles 1 and 2 including the conductor plates 5 to 8 and the strip conductors 9 to 11 forming the antenna device shown in the above first to third embodiments and the horizontally polarized waves are used. This is a case where an array antenna is formed by arranging a plurality of sets of dipoles 12 or a set of additional unexcited dipoles 14, 15, and 16. FIG. 6 illustrates the case where two sets of the configuration shown in Embodiment 3 are used and arranged in the extending direction of the vertically polarized dipole.

Further, the array antennas can be appropriately arranged in the vertical direction and the horizontal direction, and may be a two-dimensional array.
Further, it is not necessary that each of the sets arranged as a plurality of array antennas is the same set.

  As described above, the antenna device according to the fourth embodiment has the effect that it can be operated as an array antenna and the antenna gain can be increased.

Embodiment 5 FIG.
FIG. 7 is a perspective view for explaining an antenna apparatus according to Embodiment 5 of the present invention. In the fifth embodiment, side reflectors 21 and 22 are installed on both sides of the reflector 20 that forms the antenna device shown in the first to fourth embodiments. FIG. 7 illustrates the case where the present invention is applied to the configuration of the array antenna shown in the fifth embodiment.

  In addition, the side reflectors 21 and 22 are conductor plates arranged to be conductively connected to two sides substantially perpendicular to the horizontal plane of the reflector plate 20, respectively, and are connected at an inclination angle from the reflector plate 20. Here, a case of a rectangle is shown.

  Side antennas 21 and 22 are installed, the length of two sides substantially parallel to the horizontal plane corresponding to the height from reflector 20, and the inclination angle that is the angle formed with reflector 20 are changed to change the antenna. There is an effect that the beam width of the vertically polarized wave and the horizontally polarized wave in the horizontal plane can be adjusted without increasing the size of the entire apparatus than adjusting only the size of the reflecting plate 20. Moreover, there is an effect that the F / B ratio (Front / Back ratio) of the antenna device can be adjusted.

In the first to fifth embodiments, the shapes of the vertically polarized dipoles 1 and 2, the horizontally polarized dipole 12, and the non-excited dipoles 14, 15, and 16 are limited to the illustrated metal plate shape. Instead, various shapes such as a linear shape, a rectangular shape, and a polygonal shape can be applied.
Further, the shape of the conductor plate 5, 6, 7, 8 of the taper balun is not limited, and various shapes such as a trapezoid and a polygon can be applied.
Further, in the above embodiment, the explanation is given by exemplifying the case where the reflector, the vertically polarized dipole, the horizontally polarized dipole, the non-excited dipole, etc. are formed of the metal plate. It may be formed above, and the same effect as described above can be obtained.

It is a perspective view for demonstrating the antenna device concerning Embodiment 1 of this invention. It is the front view and side view of an antenna apparatus which are shown in FIG. FIG. 2 is a perspective view of the antenna device showing a case where strip conductors 9, 10, and 11 are installed on the back surface of the reflecting plate 20 in the antenna device shown in FIG. 1. It is a perspective view for demonstrating the antenna device which concerns on Embodiment 2 of this invention. It is a perspective view for demonstrating the antenna device which concerns on Embodiment 3 of this invention. It is a perspective view for demonstrating the antenna device concerning Embodiment 4 of this invention. It is a perspective view for demonstrating the antenna device concerning Embodiment 5 of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 Vertically polarized dipole, 2 Vertically polarized dipole, 3 Feeding part, 4 Feeding part, 5 Conductor plate, 6 Conductor plate, 7 Conductor plate, 8 Conductor plate, 9 Strip conductor, 10 Strip conductor, 11 Strip conductor, 12 Horizontally polarized dipole, 13 Feeding part, 14 Non-excited dipole, 15 Non-excited dipole, 16 Non-excited dipole, 20 Reflector, 21 Side reflector, 22 Side reflector, 30 Small hole, 31 Small hole

Claims (10)

A first vertically polarized dipole having an electrical length of about half a wavelength at the substantially center frequency that is provided in front of the reflector and substantially parallel to the reflector and resonates at an approximately center frequency of a use frequency band; And a second vertically polarized dipole and a horizontally polarized dipole, a first vertically polarized dipole, and a feed line to the second vertically polarized dipole, and the first vertically polarized dipole. The wave dipole and the second vertically polarized dipole are arranged substantially in parallel and in the same direction, and the horizontally polarized dipole includes the first vertically polarized dipole and the second vertically polarized dipole. The feed lines are branched and extended so that they are perpendicular to each other and do not overlap with each other, and are connected to the feed portion of the first vertical polarization dipole and the feed portion of the second vertical polarization dipole, respectively. The antenna device electrical length which is is characterized by having a substantially first feed line 1/4 odd multiple of the length of the wavelength at the center frequency and a second feed line of the frequency band. Mode conversion means for converting from an unbalanced mode to a balanced mode is provided in the first feeding line and the second feeding line, and the first feeding line and the second feeding line are respectively connected to the first vertical line. 2. The antenna device according to claim 1, wherein the mode conversion means is connected to a feeding part of a polarization dipole and a feeding part of the second vertical polarization dipole. The mode conversion means includes: a portion of the first feed line between the feeding portion of the first vertically polarized dipole and the reflecting plate; and a feeding portion of the second vertically polarized dipole; 3. The antenna device according to claim 2, wherein the antenna device is a taper balun formed at a portion of the second feed line between the reflector and the reflector. The antenna device according to claim 1, 2, or 3, wherein at least a part of the feeder line is disposed behind the reflector. In the vicinity of each of the first vertical polarization dipole, the second vertical polarization dipole, and the horizontal polarization dipole, a first non-excitation dipole and a second non-excitation dipole facing each other, and 3. A third non-excited dipole is provided, and the electrical lengths of the first non-excited dipole and the second non-excited dipole are made shorter than about a half wavelength at an approximate center frequency of the used frequency band. The antenna device according to any one of 1 to 4. The electrical lengths of the first non-excited dipole and the second non-excited dipole are approximately half wavelengths at the upper limit frequency that resonates at the upper limit frequency of the operating frequency band, and the electrical length of the third non-excited dipole 6. The antenna apparatus according to claim 5, wherein the half-wavelength at the substantially center frequency that resonates at approximately the center frequency of the use frequency band is approximately half a wavelength. 5. The horizontal polarization dipole is bent, and the length of the orthogonal projection of the horizontal polarization dipole onto the reflector is shorter than the length of the horizontal polarization dipole. The antenna device according to any one of claims. The horizontal polarization dipole is bent, the length of the orthogonal projection of the horizontal polarization dipole onto the reflector is made shorter than the length of the horizontal polarization dipole, and the third non-excitation dipole is bent. 7. The antenna device according to claim 5, wherein the length of the orthogonal projection of the third non-excited dipole onto the reflector is shorter than the length of the third non-excited dipole. One set of the first vertical polarization dipole and the second vertical polarization dipole and the horizontal polarization dipole, or the first vertical polarization dipole and the second vertical polarization dipole An array antenna is formed by arranging a plurality of sets of the horizontally polarized dipole, the first non-excited dipole, the second non-excited dipole, and the third non-excited dipole. The antenna device according to any one of 1 to 8. The reflector has a shape having a first edge and a second edge substantially perpendicular to the horizontal polarization dipole, and a first conductor plate that is an inclined surface with respect to the reflector is connected to the first edge. And the 2nd conductor board used as the inclined surface with respect to the said reflecting plate was connected to the said 2nd edge, The antenna device of any one of Claims 1-9 characterized by the above-mentioned.

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