JP3776369B2 - Dipole antenna device with reflector and method for adjusting full width at half maximum of directivity in horizontal plane - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
TECHNICAL FIELD The present invention relates to a dipole antenna device with a reflector and a method for adjusting the half-value width of a directivity in a horizontal plane. In particular, the antenna device has a large scale like a base station antenna of a cellular phone, and antenna installation and replacement can be easily performed. The present invention relates to a reflector-equipped dipole antenna device that can adjust the half-value width of directivity in a horizontal plane without replacing an existing antenna when the beam width is narrowed.
[0002]
[Prior art]
When trying to increase the subscriber capacity with a base station antenna for mobile communication that has already started service, the half-value width of the directivity in the horizontal plane of the antenna device can be changed to cope with this. Here, in order to change the half-value width of the directivity in the horizontal plane of this antenna device, it has been conventionally necessary to replace the antenna itself, and by actually exchanging the antenna, the half-value width of the directivity in the horizontal plane is changed. It corresponded to the change.
[0003]
[Problems to be solved by the invention]
However, when exchanging the base station antenna for which service has been started, there is a drawback that the service must be interrupted and paused to perform the exchange. In addition, the cost of antenna replacement is high.
The present invention is a dipole antenna device with a reflector that solves the above-mentioned problem that can reduce the half-value width of directivity in a horizontal plane by easily disposing metal conductor columns on both sides of an existing antenna, and The half-width adjustment method of the directivity in the horizontal plane is provided.
[0004]
[Means for Solving the Problems]
In a dipole antenna device with a reflector for vertical polarization having a constant radiation level of ± 90 ° with respect to the main radiation direction, it is separated from the left and right sides of the reflector standing in parallel with the dipole antenna 1. A dipole antenna device with a reflector provided with metal conductor columns 3 erected in parallel was constructed.
In addition, metal conductor columns are erected in parallel on the left and right sides of the reflector of the dipole antenna device with reflector for vertical polarization having a constant radiation level of ± 90 ° with respect to the main radiation direction. The horizontal plane of the dipole antenna device with a reflector adjusts the half width of directivity in the horizontal plane of the dipole antenna device with a reflector by changing the thickness of the metal conductor column and the distance between the metal conductor column and the dipole antenna. A half-width adjustment method for internal directivity was constructed.
[0005]
In the dipole antenna device with a reflector, the distance between the metal conductor column and the dipole antenna is set to 0.267λ, and the thickness of the metal conductor column is set to 0.067λ. Configured the device.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the present invention will be described with reference to the example of FIG.
In FIG. 1, reference numeral 1 denotes a dipole antenna erected in the vertical direction. Reference numeral 2 denotes a semicylindrical reflector having a semicircular cross section, which is also erected in parallel with the dipole antenna. The dipole antenna 1 is installed at the center in the height direction and width direction of the semi-cylindrical reflector 2 with its center portion corresponding thereto. The dipole antenna 1 is excited from the center by an excitation source, and the ground end of the excitation source and the reflector are connected to a common potential point. The semi-cylindrical reflector 2 constitutes a reflector.
[0007]
The above is a conventional dipole antenna device with a reflector for vertical polarization, but the present invention is such that a metal conductor column indicated by 3 is attached to this conventional dipole antenna device with a reflector. The metal conductor pillars 3 are disposed on both the left and right sides of the semicylindrical reflector 2 so as to be spaced apart from each other, and are erected in parallel with the dipole antenna 1 and the semicylindrical reflector 2.
The dipole antenna device with a reflector described above is oriented in the horizontal plane of the dipole antenna device with a reflector by changing the thickness R of the metal conductor column 3 and the distance d between the metal conductor column 3 and the dipole antenna 1. It can be adjusted to narrow the half width of the sex.
[0008]
Here, with reference to FIG. 2, it is a figure which shows the radiation pattern of the 120 degree beam antenna of the dipole antenna apparatus with a reflector for the vertical polarization | polarized_light for which the metal conductor pillar 3 is not attached. In FIG. 2, the level of the outermost circle is 0 dB, the center is −30 dB, and the interval between concentric circles is 5.0 dB. The half width of directivity in the horizontal plane of this conventional example is 112.38 °.
FIG. 3 is a diagram showing a change in half width of a dipole antenna device with a reflector in which a metal conductor column 3 according to the present invention is added to a conventional example.
[0009]
FIG. 3A is obtained by changing the distance d between the metal conductor column 3 and the dipole antenna 1 while setting the thickness R of the metal conductor column 3 as one parameter to R = 0.067λ. It is data. In this experimental example, the full width at half maximum when the metal conductor column 3 is not attached is 113 °. On the other hand, when the metal conductor column 3 is attached, the half-value width of the directivity in the horizontal plane decreases almost monotonically from 98 ° to 64 ° over d = 0.2 to 0.54λ. Thus, the effect of reducing the full width at half maximum of the directivity in the horizontal plane is recognized.
[0010]
FIG. 3B is obtained by setting the distance d between the metal conductor column 3 and the dipole antenna 1 which is the other parameter to d = 0.267λ, and changing the thickness R of the metal conductor column 3. It is data. In this experimental example, the full width at half maximum when the metal conductor column 3 is not provided is almost the same as the previous experimental example. On the other hand, when the metal conductor pillar 3 is attached, the effect of reducing the half-value width of the directivity in the horizontal plane over R = 0.02 to 0.07λ is recognized. However, in the range of R = 0.07λ or more, even if the thickness R of the metal conductor column 3 is changed, the effect of reducing the half width of the directivity in the horizontal plane is hardly recognized.
[0011]
In FIG. 4, the metal conductor column 3 according to the present invention is attached, and the distance between the metal conductor column 3 and the dipole antenna 1 is set to d = 0.267λ, while the thickness of the metal conductor column 3 is set to R = 0. It is a figure which shows the radiation pattern of the dipole antenna device with a reflector at the time of setting to .067λ. In FIG. 4, as in FIG. 2, the level of the outermost circle is 0 dB, the center is −30 dB, and the interval between concentric circles is 5.0 dB. In this case, the half-value width of the directivity in the horizontal plane is 85.19 °, which is greatly reduced as compared with the half-value width of directivity in the horizontal plane of 112.38 ° in the conventional example of FIG.
[0012]
FIG. 5 shows the beam conductors having a half-value width of 180 °, 120 °, 90 °, and 60 ° in the horizontal directionality, and the thickness of the metal conductor column 3 is set to R = 0.067λ. It is a figure which shows the change of the half value width of the directivity in a horizontal surface which changed d the distance between the antenna and the dipole antenna 1. In any case, it is possible to recognize the effect of reducing the half-value width of the directivity in the horizontal plane in proportion to the distance d.
2 and 4, and the half-value width of the directivity in the horizontal plane of FIGS. 3 and 5 use software for calculating the electromagnetic field distribution numerically, the type of antenna, the length of the antenna, the excitation frequency of the excitation source, The shape of the reflector, the size of the reflector, the feeding point, the positional relationship between the antenna and the reflector, and other conditions are input and calculated by an electronic computer.
[0013]
In the embodiment shown in FIG. 1, the following conditions are set.
(B) Software for numerical calculation of electromagnetic field distribution: PLANC-MM (Information Mathematical Research Laboratories)
(B) Antenna type: Dipole antenna (c) Antenna length: 0.5λ
(D) Excitation frequency of excitation source: 2,000 GHz
(E) Reflector shape structure: semi-cylindrical, semi-circular conductor in cross section, metal conductor columns (f) reflectors spaced apart on the left and right sides of the semi-circular conductor in cross-section dimensions:
Distance between dipole antenna and metal conductor post; d = 0.2-0.54λ
Thickness of metal conductor column; R = 0.01-0.24λ / 4
(G) Feeding point: central part of the antenna (h) Positional relationship between the antenna and the reflector: installation in the above embodiment, with the central part of the antenna corresponding to the center in the height direction and the width direction of the reflector. Although the reflector which comprises is made into the semi-cylindrical reflector 2, this can be implemented by making this into a mere reflector.
[0014]
【The invention's effect】
As described above, according to the present invention, the communication service is provided by providing the metal conductor pillars standing in parallel on the left and right sides of the reflector standing in parallel with the dipole antenna. The base station's dipole antenna device with reflector is oriented in the horizontal plane only by attaching a metal conductor column without replacing the dipole antenna itself and interrupting service. It is possible to easily cope with an increase in subscriber capacity by reducing the half width of the sex.
[Brief description of the drawings]
FIG. 1 illustrates an example.
FIG. 2 is a diagram showing a radiation pattern of a conventional example.
FIG. 3 is a diagram illustrating a change in half-value width of directivity in a horizontal plane according to an embodiment.
FIG. 4 is a diagram showing a radiation pattern of an embodiment in which a distance d and a thickness R are specified.
FIG. 5 is a diagram showing that the effect of reducing the half-value width of the directivity in the horizontal plane is recognized in proportion to the distance d without depending on the half-value width of the beam antenna.
[Explanation of symbols]
1 Dipole antenna 2 Semi-cylindrical reflector 3 Metal conductor pillar

Claims (3)

In a dipole antenna device with a reflector for vertical polarization having a radiation level symmetric within a range of ± 90 ° with respect to the main radiation direction in the horizontal plane,
Metal conductor pillars are provided on both the left and right sides parallel to the dipole antenna, separated from the reflectors,
These metal conductor columns have a thickness of 0.02λ to 0.07λ, and the distance from the dipole antenna is 0.2λ to 0.54λ,
The reflector is a semi-cylindrical reflector, the dipole antenna is located on the center line of the semi-cylindrical reflector, and the metal conductor columns are located on the left and right outer sides with respect to both side edges of the semi-cylindrical reflector. A dipole antenna device with a reflector.
A dipole antenna device with a reflector. In the dipole antenna device with a reflector according to claim 1 ,
A dipole antenna device with a reflector, wherein the distance between the metal conductor column and the dipole antenna is set to 0.267λ and the thickness of the metal conductor column is set to 0.067λ. The directivity in the horizontal plane has a symmetric radiation level in the range of ± 90 ° with respect to the main radiation direction, and the dipole antenna is 0 on each of the left and right sides of the semi-cylindrical reflectors standing in parallel with the dipole antenna. .2λ-0.54λ apart from each other and provided with a metal conductor column having a thickness of 0.02λ-0.07λ, which is erected in parallel with the dipole antenna, and the dipole antenna is on the center line of the semi-cylindrical reflector With respect to the dipole antenna with reflectors, the metal conductor pillars are located on the left and right outer sides with respect to both side edges of the semi-cylindrical reflector ,
By adjusting the half width of the directivity in the horizontal plane of the dipole antenna device with a reflector by changing the thickness of the metal conductor column and the distance between the metal conductor column and the dipole antenna. A half-value width adjusting method for directivity in a horizontal plane of a dipole antenna device.

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