JPH05191141A - Plane antenna - Google Patents

Abstract

PURPOSE:To obtain a plane antenna which can reduce the side robe level and ensure the satisfactory antenna characteristic. CONSTITUTION:A plane antenna consists of an earth conductor plate 3, a feeder circuit plate 2, and a radiating circuit plate 1 which are successively laminated on each other via a dielectric layer 4 like an air layer, etc., and with the fixed spaces secured among these component elements. The radiating elements 5 of the plate 1 are electromagnetically connected to the feeder probes 2b of the plate 2 respectively with no contact. The length of the probe 2b is set at 9.25mm at the center part of an entire antenna and then reduced every 0.25mm toward the peripheral part. Thus the radiating power of the element 5 is successively increased toward the center part from the peripheral part of the antenna.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a planar antenna.

[0002]

2. Description of the Related Art As a planar antenna for receiving radio waves from a broadcasting satellite or a communication satellite, a radiation circuit board having a plurality of radiating elements and a non-radiating element formed on the radiating elements are provided in order to achieve high efficiency and wide bandwidth. An array antenna having a so-called tri-plate structure, which is formed by laminating a power supply circuit board on which a power supply circuit for electromagnetically connecting a power supply probe by contact with each other and forming a power supply is laminated on a ground conductor plate via a dielectric layer. Is being developed.

[0003]

However, since this type of array antenna generates a relatively high side lobe, it becomes easy to receive unnecessary radio waves from other satellites adjacent to the satellite intended for reception. There was a problem of causing interference. The present invention has been made in view of the above problems, and an object of the present invention is to provide a planar antenna having an array antenna configuration in which the side lobe level is reduced and good antenna characteristics are obtained.

[0004]

In order to achieve the above-mentioned object, the invention according to claim 1 is such that the radiation circuit board and the feeding circuit board are not in contact with each other, and the radiation element and the feeding probe are electromagnetically coupled. In a planar antenna, the power supply circuit formed on the power supply circuit board is provided with an unequal power distribution part so that the power to be supplied is larger in the radiating element located in the central part of the antenna than in the peripheral part. It is a thing.

According to a second aspect of the present invention, in the planar antenna in which the radiation circuit board and the feeding circuit board are not in contact with each other and the radiation element and the feeding probe are electromagnetically coupled, the shape of the radiation element of the radiation circuit board is changed. The radiating element is sequentially changed from the radiating element located in the central part of the antenna to the radiating element located in the peripheral part of the antenna so that the radiated power is gradually reduced from the central part to the peripheral part of the antenna.

According to a third aspect of the present invention, in a planar antenna in which the radiation circuit board and the feeding circuit board are not in contact with each other and the radiation element and the feeding probe are electromagnetically coupled, the radiation power is from the central portion of the antenna to the periphery. The shape of the feeding probe of the feeding circuit board located in the central portion of the antenna is made different from the shape of the feeding probe located in the peripheral portion of the antenna so that it becomes smaller gradually toward the portion.

According to a fourth aspect of the present invention, in the first aspect of the present invention, the shape of the feeding probe of the feeding circuit board is such that the feeding probe located in the central portion of the antenna is located in the peripheral portion of the feeding probe. It is the one that is sequentially changed over the probe. The invention described in claim 5 is claim 1
In the described invention, the shape of the radiating element of the radiating circuit board,
The radiating element located in the central portion of the antenna is changed to the radiating element located in the peripheral portion.

According to a sixth aspect of the present invention, in the first aspect of the invention, the shape of the feeding probe of the feeding circuit board and the shape of the radiating element of the radiating circuit board are changed from those located in the central portion of the antenna to the peripheral portion. It is the one that is gradually changed depending on the position.

[0009]

According to the present invention, therefore, the radiation (feeding) power can be reduced from the central portion of the antenna to the peripheral portion thereof, so that the level of the side lobe lobe can be greatly reduced, resulting in interference. A planar antenna consisting of an array antenna that is difficult and has good antenna performance has been realized.

[0010]

EXAMPLES The present invention will be described below with reference to examples. (Embodiment 1) This embodiment shows an exploded perspective view in which a part of FIG. 1 is omitted. In this embodiment, a ground conductor plate 3, a feeding circuit board 2 and a radiation circuit board 1 are used as a dielectric layer such as an air layer. 4 are separated by a certain distance and sequentially laminated.

The radiation circuit board 1 is made of a metal plate such as aluminum having a thickness of 0.5 mm and has, for example, 15 sides.
Twenty-four radiating elements 5 each having an aperture of a square of mm are punched out at equal intervals in the vertical and horizontal directions. The power supply circuit board 2 is made of, for example, a flexible board in which a copper foil is laminated on a polyester board, and a power supply circuit including a power supply line 2a to which a power supply probe 2b electromagnetically coupled to each radiation element 5 of the radiation circuit board 1 is added is etched. It is formed by.

The ground conductor plate 3, which is arranged below the power feeding circuit plate 2 with a certain distance, is formed of a commercially available metal plate such as aluminum. The power supply probe 2b formed on the power supply circuit board 2 has the shape shown in FIG. 2. For example, in the case where the length L is located in the central portion of the antenna,
Formed to 25 mm, 0.25 m as it goes to the periphery
It is made smaller by m.

In the planar antenna comprising the array antenna of the first embodiment obtained as described above, the radiated power of the radiating element 5 gradually decreases from the central portion of the antenna to the peripheral portion thereof, so that the side lobe level is reduced. It was possible to reduce. That is, in this embodiment, 12.25 to 12.75 GH
It was confirmed that a side lobe characteristic of 18 dB or more was realized with a reception efficiency of 60% or more over the z band.

(Embodiment 2) In Embodiment 1, the feeding probe 2b is sequentially deformed, but the shape of the radiating element 5 may be sequentially deformed. In this embodiment, for example, the radiating element 5 in FIG. 1 is used. The shape of the antenna is 16
mm square aperture, and a square aperture whose side length is reduced by 0.25 mm in order over the peripheral portion, so that the radiated power gradually decreases from the central portion of the antenna to the peripheral portion. It was done.

It has been confirmed that the planar antenna of this embodiment has the same performance as that of the first embodiment. (Embodiment 3) In this embodiment, in the planar antenna having the configuration shown in FIG. 1, the antenna radiation power is inclined to the feeding line 2a, the radiation power from the central portion of the antenna is 1, and radiation from the peripheral portion (feeding). ) A T-branch 2c for allocating the electric power non-uniformly is arranged so that the electric power becomes 0.2.

When the radiation directivity of the antenna of the present embodiment constructed as described above was measured, the result shown in FIG. 3 was obtained, and the side lobe level was set to −15 [d].
B] could be reduced to the following. (Embodiment 4) This embodiment is a combination of the configurations of Embodiments 1 and 3, and in the antenna configuration of FIG. 1, the length L of the feeding probe 2b formed on the feeding circuit board 2 is set at the center of the antenna. The one located at the portion is formed to have a size of 9.25 mm, and is made smaller by 0.1 mm toward the peripheral portion. In addition, the power supply line 2a is provided with an inclination to the antenna radiation power, and the power is unequally distributed so that the radiation power from the central portion of the antenna is 1 and the radiation (feeding) power from the peripheral portion is 0.5. The T branch 2c is arranged.

It was confirmed that the planar antenna of this embodiment also has the same performance as that of the first embodiment. (Embodiment 5) This embodiment is a combination of the configurations of Embodiments 2 and 3, and in the antenna configuration of FIG. 1, the radiating element 5 has a square aperture with a side of 16 mm at the center of the antenna. It is formed with a square aperture whose side length is successively reduced by 0.1 mm over the peripheral portion. In addition, the power supply line 2a is provided with an inclination to the antenna radiation power, and the power is unequally distributed so that the radiation power from the central portion of the antenna is 1 and the radiation (feeding) power from the peripheral portion is 0.5. The T branch 2c is arranged.

It was confirmed that the planar antenna of this embodiment also has the same performance as that of the first embodiment. Although the linearly polarized light aperture is provided as the radiating element 5 in the above-described embodiment, the present invention is not limited to circularly polarized light, but left circularly and right circularly dual circularly polarized waves, and horizontally and vertically dually polarized waves. It goes without saying that it can be applied to a polarized plane antenna.

[0019]

Since the present invention is configured as described above, it is possible to reduce the radiated power from the central portion of the antenna to the peripheral portion thereof, and thus it is possible to greatly reduce the level of the side lobe. There is an effect that it is possible to realize a planar antenna which is an array antenna having good antenna performance, in which interference hardly occurs.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of a first embodiment of the present invention with a part thereof omitted.

FIG. 2 is a top view of the dimension explanatory view part of the power supply probe according to the first embodiment of the present invention.

FIG. 3 is a characteristic explanatory diagram of Example 3 of the present invention.

[Explanation of symbols]

 1 Radiation Circuit Board 2 Feeding Circuit Board 2b Feeding Probe 3 Ground Conductor Plate 4 Dielectric Layer 5 Radiating Element

Claims (6)

[Claims] 1. A flat antenna in which a radiation circuit board and a power feeding circuit board are not in contact with each other and in which a radiation element and a power feeding probe are electromagnetically coupled to each other, a non-uniform power distribution to a power feeding circuit formed on the power feeding circuit board. A planar antenna characterized in that a radiating element located in the central part of the antenna has a larger power to be fed by providing a part than that in the peripheral part. 2. In a planar antenna in which the radiation circuit board and the feeding circuit board are not in contact with each other and the radiation element and the feeding probe are electromagnetically coupled to each other, the shape of the radiation element of the radiation circuit board corresponds to the radiation power of the antenna. A planar antenna characterized in that it is sequentially changed from a radiating element located in the central part of the antenna to a radiating element located in the peripheral part of the antenna such that the radiating element is gradually reduced from the central part to the peripheral part. 3. In a planar antenna in which the radiation circuit board and the feeding circuit board are not in contact with each other and in which the radiation element and the feeding probe are electromagnetically coupled, the radiation power is gradually reduced from the central portion to the peripheral portion of the antenna. In addition, the planar antenna is characterized in that the shape of the feeding probe of the feeding circuit board located in the central portion of the antenna is different from the shape of the feeding probe located in the peripheral portion of the antenna. 4. The shape of the feeding probe of the feeding circuit board is changed sequentially from the feeding probe of the feeding circuit board located in the central portion of the antenna to the feeding probe located in the peripheral portion. The plane antenna described. 5. A planar antenna, characterized in that the shape of the radiating element of the radiating circuit board is changed sequentially from the radiating element located in the central part of the antenna to the radiating element located in the peripheral part. 6. The shape of the feeding probe of the feeding circuit board and the shape of the radiating element of the radiating circuit board are sequentially changed from those located in the central portion of the antenna to those located in the peripheral portion. Item 2. The planar antenna according to Item 1.