JP3701578B2 - Horizontal and vertical polarization antenna device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a polarization sharing antenna apparatus using horizontal polarization and vertical polarization suitable as a base station antenna of a mobile communication system such as an automobile mobile phone or PHS (simple mobile phone system).
[0002]
[Prior art]
Conventionally, with respect to this type of antenna device, in recent years, the installation form of a base station antenna in a land mobile communication system has used a space diversity reception system in order to increase the reception efficiency of radio waves. The top shape is larger. Accordingly, the tower equipment of the base station is large and costly, and further detracts from the beauty.
[0003]
However, when the polarization diversity reception system is used, the shape of the upper part of the steel tower can be reduced, the base station equipment can be simplified, and there are many advantageous aspects in terms of aesthetics. When performing polarization diversity, in order to form the same area for both transmission and reception, both the horizontal polarization for reception and the vertical polarization for both transmission and reception share polarization with the same directional half-value angle in the horizontal plane. An antenna is required.
[0004]
For example, in the case of a three-sector configuration, it is necessary to arrange a polarization sharing antenna having a horizontal half-directional directivity half-value angle and 120 degrees directivity for both horizontal and vertical polarization. As a conventional dual-polarized antenna, as shown in FIG. 6, dipole antennas 102 and 102 supported and fed by a feed line 104 are crossed on the front surface of a metal reflector 103, and one of them is used for horizontal polarization. Some use a dipole antenna 101 or the like in which the other is installed for vertical polarization.
Further, there is a structure in which the metal reflector 103 is formed in a corner reflector and the cross dipole antenna 101 is disposed on the front surface thereof.
[0005]
[Problems to be solved by the invention]
However, when the sector is constituted by the base station of the mobile communication system using the conventional cross dipole antenna 101, the directivity of the transmission / reception antenna is required to be equal. In particular, when both the horizontally polarized antenna and the vertically polarized antenna are configured by dipole antennas, the dipole antenna has different directivities on the electric field surface and the magnetic field surface. There was a problem that the directivity in the horizontal plane was not equal.
[0006]
The present invention has been made in view of the above points, and an object of the present invention is to provide a horizontal and vertical polarization antenna apparatus that eliminates the above-described problems and has horizontal and vertical polarization having the same directivity in the horizontal plane. It is in.
[0007]
Another object of the present invention is to provide a horizontal and vertical polarization antenna device that can change the directivity characteristics in the horizontal plane of the vertical polarization antenna without impairing the directivity characteristics in the horizontal plane of the horizontal polarization antenna.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the present invention has a structure in which slots are formed in dielectric substrates each having a metal foil attached, which are arranged at approximately 90 degrees with a gap between end portions. Two sets of horizontally polarized antennas each including an antenna and a parasitic element disposed on the outer front surface thereof, and the gaps formed by the respective dielectric substrates of the horizontally polarized antennas are disposed through the gaps. A dipole antenna formed on both surfaces of the dielectric substrate and a parasitic element disposed in front of the dipole antenna, the dipole antenna being directed outward and formed in a vertical direction It is a horizontal and vertical polarization antenna apparatus including a polarization antenna and a corner reflector on which the two sets of horizontal polarization antennas and the vertical polarization antenna are disposed.
[0009]
The corner reflector is a reflector disposed at approximately 45 degrees behind the two sets of slot antennas and with respect to the respective dielectric substrates of the slot antennas, and both horizontal end portions thereof are The horizontal polarization antenna is bent at a right angle with respect to the respective dielectric substrate toward the end of the respective dielectric substrate, and the horizontal polarization antenna and the vertical polarization antenna are the same. This is a horizontal and vertical polarization antenna apparatus that is fed with frequency power and is fed so that radio waves radiated from the slot antennas of the horizontally polarized antenna are in phase.
[0010]
The two sets of horizontally polarized antennas and vertically polarized antennas are horizontal and vertically polarized antenna apparatuses that are alternately arranged in the vertical direction.
[0011]
Further, in the horizontal and vertical polarization antenna apparatus, a notch is provided in a portion corresponding to the center of the vertical polarization antenna of each dielectric substrate of the horizontal polarization antenna.
[0012]
In the horizontal and vertical polarization shared antenna apparatus, the cut-out portion is formed symmetrically with respect to the vertical polarization antenna, and is formed in a substantially isosceles triangle shape having two sides formed from a plurality of step portions.
[0013]
With the configuration as described above, the present invention can make horizontal directivity in horizontal plane and vertical polarization equal. Furthermore, by providing the notch, the horizontal plane directivity of the vertically polarized antenna can be changed without impairing the horizontal plane directivity of the horizontally polarized antenna.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.
[0015]
1 to 5 are views showing an embodiment of the horizontal and vertical polarization antenna device of the present invention. FIG. 1 is a front view of the polarization antenna device, and FIG. 2 is a bottom surface of FIG. FIG. 3, FIG. 3 is a right side view of the vertically polarized antenna of FIG. 1, FIG. 4 is a diagram showing a horizontal plane directivity characteristic of the horizontally polarized antenna of the antenna apparatus of FIG. 1, and FIG. It is a figure which shows the directional characteristic in the horizontal surface of the vertically polarized antenna of an antenna apparatus.
[0016]
1 and 2, the horizontal and vertical polarization antenna apparatus 1 includes two sets of horizontal polarization antennas 2 and 3 including slot antennas 6 and 7 arranged in the vertical direction, respectively. A vertically polarized antenna 4 composed of a pair of dipoles arranged in a vertical direction so as to pass through a gap 9 formed between the horizontally polarized antennas 2 and 3; the horizontally polarized antennas 2 and 3; It comprises a corner reflector 5 disposed behind the vertically polarized antenna 4.
[0017]
The two sets of horizontally polarized antennas 2 and 3 have the same configuration and are symmetrically formed around the vertically polarized antenna 4, and a metal foil is attached to one surface as the slot antennas 6 and 7. Two dielectric substrates (for example, relative permittivity of the substrate 3.4, thickness 1.6 mm) 11 and 12 are arranged at approximately 90 degrees with respect to each other in a horizontal plane with a gap 9 between their ends. In the dielectric substrates 11 and 12, elongated slots 13 and 14 are formed in the vertical direction. At the same time, in the radiation direction of the slot antennas 6, 7, on the outer (dominant side) front surface formed by the two dielectric substrates 11, 12, in front of the slots 13, 14, the slot antenna 6 , 7 are parallel to the dielectric substrates 11 and 12 at positions where the wavelength λ of the operating frequency is about 0.03λ and about 0.10λ (each interval is about 0.07λ). A plurality of (two in the present embodiment) parasitic element plates 15, 16; 17, 18 are disposed.
The two sets of horizontally polarized antennas 2 and 3 are arranged in the vertical direction.
[0018]
Each of the slots 13 and 14 of the slot antennas 6 and 7 has a vertical length of about 0.29λ of the wavelength λ of the used frequency, and a horizontal width of about 0.02λ. The parasitic element plates 15, 16; 17, 18 disposed respectively in front of the slot antennas 6, 7 have a vertical length of about 0.25λ and a horizontal width of about 0.3λ. is there. Here, 19a and 19b; 20a and 20b are feed lines to the slot antennas 6 and 7, respectively.
[0019]
As shown in FIGS. 2 and 3, the vertically polarized antenna 4 extends vertically through the gaps 9 formed by the dielectric substrates 11 and 12 of the horizontally polarized antennas 2 and 3, respectively. A dipole antenna 8 formed on a metal foil attached to both surfaces of a dielectric substrate (for example, relative dielectric constant 2.6, thickness 0.8 mm) 21 of the dielectric substrate, It consists of a parasitic element 22 that is close to and parallel to the dipole elements 8a and 8b in the forward direction (radiation direction).
[0020]
The vertically polarized antenna 4 protrudes on the radial direction side of the slot antennas 6 and 7 on the center line of the angle (90 degrees) formed by the dielectric substrates 11 and 12 of the horizontally polarized antennas 2 and 3. Are arranged in the same direction as the radiation direction, and are arranged in a plurality of stages at symmetrical positions in the vertical direction around the center line in the width direction of the slots 13 and 14 of the slot antennas 6 and 7. Is done. That is, the vertically polarized antennas 4 are arranged alternately with the horizontally polarized antennas 2 and 3 in the vertical direction.
[0021]
The dipole elements 8a and 8b constituting the dipole antenna 8 of the vertically polarized antenna 4 are arranged at the center of the dipole antenna 8 on both sides of the dielectric substrate 21 so as to resonate at a use frequency, for example, 2.0 GHz. The dipole elements 8a and 8b are rotated exactly 180 degrees around the central axis of the dipole antenna 8 with respect to the feed lines 23a and 23b formed in the section. Formed in position. The distance between both ends of the dipole elements 8a and 8b is usually about ½ of the wavelength λ of the frequency and may be ½ or less.
[0022]
The dipole elements 8a and 8b of the dipole antenna 8 are connected to the feed lines 23a and 23b through a central feed point. Reference numeral 24 denotes a grounding portion connected to the feed line.
[0023]
The parasitic element 22 formed on the dielectric substrate 21 is disposed in parallel to the dipole elements 8a and 8b in the radial direction on the central axis of the dipole elements 8a and 8b, and is different from the operating frequency. It has a length that resonates with the frequency.
The parasitic element 22 is formed such that the length of both ends thereof is about ½ of the wavelength of the different frequency (frequency higher than the used frequency), the width thereof is arbitrary, and the dipole 8 Is arranged at an arbitrary distance from
The horizontal polarization antennas 2 and 3 (the slot antennas 6 and 7), the dielectric substrates 11 and 12, the parasitic element plates 15 and 16; 17, 18 and the vertical polarization antenna 4 are illustrated. The corner reflector 5 is supported by a non-supporting member.
[0024]
The corner reflecting plate 5 is substantially 45 degrees behind the two sets of the slot antennas 6 and 7 with respect to the dielectric substrates 11 and 12 of the slot antennas 6 and 7, respectively, at substantially the center position thereof. The vertical polarization antenna 4 is disposed substantially at right angles.
The corner reflector 5 is bent so that the end portions 25, 25 on both sides in the horizontal direction are parallel to the dielectric substrates 11, 12 of the horizontally polarized antennas 2, 3 in the middle. After being bent (bent back approximately 135 degrees), the end portions 25, 25 on both sides are directed substantially perpendicular to the dielectric substrates 11, 12 toward the ends of the dielectric substrates 11, 12. It is bent.
[0025]
Further, notches 30 and 30 are provided at portions of the respective dielectric substrates 11 and 12 of the horizontally polarized antennas 2 and 3 corresponding to the center of the vertically polarized antenna 4. The notches 30 and 30 are formed symmetrically around the vertically polarized antenna 4 and the two sides thereof are formed in a substantially isosceles triangle shape formed by a plurality of step portions 30a and 30a. Yes.
Since the notched portions 30 and 30 are provided, the dual-polarized antenna device 1 impairs the horizontal plane directivity of the vertical polarization antenna 4 and the horizontal plane directivity of the horizontal polarization antennas 2 and 3. There is no change.
In addition to the above, the notches 30 and 30 may be semicircular or semielliptical having a plurality of stepped portions 30a.
[0026]
In the dual-polarized antenna device 1, the horizontally polarized antennas 2 and 3 and the vertically polarized antenna 4 are fed with power of the same frequency, and each of the slot antennas of the horizontally polarized antennas 2 and 3 is provided. Electric power is fed so that the radio waves radiated from 6 and 7 are in phase.
[0027]
4 and 5 show the horizontal plane directivity characteristics of the horizontally polarized antennas 2 and 3 of the dual polarization antenna apparatus 1 and the horizontal plane directivity characteristics of the vertical polarization antenna 4. The relative electric field strength (dB) is shown with respect to the azimuth angle with the front direction of. As can be seen from the figure, the directivity characteristics in the horizontal plane of both polarization antennas 2, 3; 4 are substantially the same.
[0028]
Note that the technology of the present invention is not limited to the technology in the above-described embodiment, and may be implemented by means of other modes that perform the same function, and the technology of the present invention may be variously modified within the scope of the above-described configuration. Can be added.
[0029]
【The invention's effect】
As is clear from the above description, according to the horizontal and vertical polarization dual antenna device of the present invention, the metal foils are attached to each other, which are arranged at approximately 90 degrees with a gap between the end portions. Formed on the dielectric substrate are two sets of horizontally polarized antennas each formed of a slot antenna and a parasitic element disposed on the outer front surface thereof, and the respective dielectric substrates of the horizontally polarized antennas. A dipole antenna formed on both surfaces of the dielectric substrate and a parasitic element disposed in front of the dipole antenna, the dipole antenna being directed outward. A vertically polarized antenna formed in a vertical direction and a corner reflector on which the two sets of horizontally polarized antennas and the vertically polarized antenna are disposed. Horizontal Pattern with can be made equal.
[0030]
In addition, since a notch is provided in a portion of each of the dielectric substrates of the horizontally polarized antenna corresponding to the center of the vertically polarized antenna, the directivity characteristics in the horizontal plane of the vertically polarized antenna are There is an excellent effect that it can be changed without impairing the directivity characteristics in the horizontal plane of the polarization antenna.
[Brief description of the drawings]
FIG. 1 is a front view showing an embodiment of a shared antenna for horizontal and vertical polarization according to the present invention.
FIG. 2 is a bottom view of FIG.
FIG. 3 is a right side view of the vertically polarized antenna shown in FIG. 1;
4 is a diagram showing a horizontal plane directivity characteristic of the horizontally polarized antenna of the antenna apparatus of FIG. 1; FIG.
FIG. 5 is a diagram showing a horizontal plane directivity characteristic of the vertically polarized antenna of the antenna apparatus of FIG. 1;
FIG. 6 is a perspective view of a cross dipole antenna as a conventional dual-polarized antenna.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Horizontal and vertical polarization antenna apparatus 2, 3 Horizontal polarization antenna 4 Vertical polarization antenna 5 Corner reflector 6, 7 Slot antenna 8 Dipole antenna 8a, 8b Dipole element 11, 12, 21 Dielectric board | substrate 13, 14 Slot 15, 16, 17, 18 Parasitic element plates 19a, 19b, 20a, 20b, 23a, 23b Feed line 22 Parasitic element 24 Grounding part 25 Side end (reflecting plate)
30 Notch 30a Step

Claims (5)

A slot antenna formed on a dielectric substrate having a metal foil attached to each other, and a parasitic power source disposed on the outer front surface thereof, which are disposed at approximately 90 degrees with a gap between the end portions. Two sets of horizontally polarized antennas comprising elements;
A dipole antenna disposed on both surfaces of the dielectric substrate and a parasitic element disposed in front of the dipole antenna, which is disposed through the gap formed by the respective dielectric substrates of the horizontally polarized antenna. A vertically polarized antenna in which the dipole antenna is directed outward and formed in a vertical direction;
An antenna apparatus for both horizontal and vertical polarizations, comprising a corner reflector on which the two sets of horizontally polarized antennas and the vertically polarized antennas are disposed. The corner reflector is a reflector disposed at approximately 45 degrees behind the two sets of slot antennas and with respect to the respective dielectric substrates of the slot antennas, and both horizontal end portions thereof are Toward the end of each dielectric substrate of the horizontally polarized antenna, bent at a right angle to the respective dielectric substrate,
Further, the horizontal polarization antenna and the vertical polarization antenna are fed with power of the same frequency, and the radio waves radiated from the slot antennas of the horizontal polarization antenna are fed so that they are in phase. 2. The horizontally and vertically polarized antenna apparatus according to claim 1, wherein The horizontal and vertical polarization antenna apparatus according to claim 1 or 2, wherein the two sets of horizontal polarization antennas and the vertical polarization antennas are alternately arranged in a vertical direction. 4. The cutout portion is provided at a portion corresponding to the center of the vertically polarized antenna of each dielectric substrate of the horizontally polarized antenna. 5. Horizontal and vertical polarization antenna device. 5. The cutout portion is formed in a substantially isosceles triangle shape having two sides formed of a plurality of step portions symmetrically with respect to the vertically polarized antenna. Horizontal and vertical polarization antenna device.

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