JP3017553B2 - Planar antenna - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a planar antenna.

[0002]

2. Description of the Related Art At present, planar antennas have been put to practical use for receiving broadcast satellites. Conventional broadcast satellite receiving planar antennas have been proposed in which a strip line is bent into a crank shape and a flat antenna is formed by a plurality of patch elements.

[0003] However, these planar antennas generally have a narrow band, and it is difficult to have sufficient performance in the entire broadcast band of 300 to 400 MHz. Further, the loss from the feeder line is large, and it is difficult to improve the efficiency. Therefore, a triplate-type planar antenna composed of a ground conductor plate, a feed circuit board, and a radiation circuit board has been developed for high efficiency and wide band, and has a reception performance comparable to that of a parabolic antenna.

[0004]

However, even if the triplate-type planar antenna composed of the annular slot-type radiating element is equivalent in performance to a parabolic antenna, there is a problem in cost due to the high cost of the etching process. Further, it has been difficult to secure cross polarization characteristics over a wide band.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems. It is an object of the present invention to provide a planar antenna which can be manufactured at low cost and can secure cross polarization characteristics over a wide band. is there.

[0006]

In order to achieve the above-mentioned object, according to the first aspect of the present invention, a ground conductor plate, a feeder circuit board, and a radiation circuit board are sequentially laminated so as to be separated from each other by a dielectric, and a radiation circuit is formed. the plate forms a radiating element composed of the aperture, the planar antenna to the feeder circuit board forming the feed probe to electromagnetically coupled to said aperture, disposing the conductive element in a non-contact in the vicinity of the feed probe flush It was done.

According to a second aspect of the present invention, in the first aspect of the present invention, a pair of rectangular conductive elements are provided on the same plane with respect to the power supply probe of the power supply circuit board and on both sides of the power supply probe with a fixed distance therebetween. is there. According to a third aspect of the present invention, in the first aspect of the present invention, the shape of the aperture is a square or circular hole, and the outer edge of the aperture located at 45 degrees with respect to the extension direction of the tip of the probe. A notch or a projection protruding into the hole is provided.

According to a fourth aspect of the present invention, in the first aspect of the present invention, a pair of rectangular conductor elements are provided on the same plane with respect to the power supply probe of the power supply circuit board and on both sides of the power supply probe at a constant distance. is there. According to a fifth aspect of the present invention, in the first aspect of the present invention, a rectangular conductive element is provided on the same plane with respect to the power supply probe of the power supply circuit board and on one side of the power supply probe with a predetermined space therebetween.

According to a sixth aspect of the present invention, in the first aspect of the present invention, a pair of rectangular conductive elements are provided on both sides of the power supply circuit board on the same plane with respect to the power supply probe at a constant distance from each other. The conductor elements are partially connected. According to a seventh aspect of the present invention, in the first aspect of the present invention, the radiation circuit board is formed of a metal plate having an aperture formed by punching.

[0010]

According to the present invention, since the radiating element formed on the radiating circuit board is of the aperture type, a punching process of a metal plate which can be manufactured easily and inexpensively is employed for manufacturing the radiating circuit board. It is possible to greatly reduce the cost as compared with the conventional etching process. In addition to the electromagnetic coupling between the power supply probe and the aperture, resonance occurred between the aperture and the conductor element provided near the same plane as the power supply probe, and the band was widened. In particular, it has become possible to broaden the cross polarization characteristic, which has been a problem in the past.

According to a seventh aspect of the present invention, in the first aspect of the invention, the radiation circuit board is formed of a metal plate, and each of the slots and apertures are formed by punching. The accuracy of the distance between the ground conductor, feed circuit board, and radiation circuit board is improved because
The variation in antenna performance became extremely small.

[0012]

The present invention will be described below with reference to examples. (Embodiment 1) As shown in a partially omitted exploded perspective view of FIG. 1 and a partially omitted sectional view of FIG.
The power supply circuit board 2 and the radiation circuit board 3 are sequentially laminated so as to be separated from each other by a dielectric 11.

The radiating circuit board 3 is made of a metal plate such as aluminum having a thickness of 0.4 mm, and is formed by punching square apertures 4 each having a side of 16 mm with a pitch between centers of 20 mm at 16 rows and 16 columns. It is. The feeder circuit board 2, which is arranged below the radiating circuit board 3 at a predetermined interval (for example, 1 mm), is made of a flexible board in which a copper foil is laminated on a polyester board having a thickness of 50 μm, and each aperture 4 of the radiating circuit board 3 is provided. Power supply probe 5a corresponding to
And a crank-shaped circuit to which these power supply probes 5a are connected, are formed by etching, and concave conductor elements (FIG. 3) are sandwiched so as to sandwich each power supply probe 5a with a gap of 0.5 mm between both side pieces. A power supply circuit is formed by additionally forming a plastic element 6) by etching.

The power supply probe 5a and the conductor element 6 are positioned so as to be electromagnetically coupleable to the corresponding aperture 4, and the conductor element 6 resonates with the aperture 4 to strengthen the electromagnetic coupling. do. The length of the long side of the conductor element 6 is 9 mm, and the length of the short side is 5 m.
m (2 mm). The ground conductor 1 disposed at a fixed interval (for example, 2 mm) below the power supply circuit board 2 is formed of a metal plate such as a commercially available aluminum having a thickness of 2 mm.

Thus, the power supply probe 5a and the conductor element 6 of the power supply circuit board 2 are provided within the projection of the aperture 4 of the radiation circuit board 3.
, The circuit boards 3 and 2 and the ground conductor board 1 are sequentially laminated, and a dielectric member 7 made of a foamed plastic sheet having a function as a spacer is interposed therebetween to form a planar antenna. . As the dielectric 7, an air layer may be used instead of the foamed plastic sheet.

When the VSWR, gain, and cross-polarization characteristics of the planar antenna according to the first embodiment obtained as described above were measured, a wide band of 11.2 to 12.2 GHz (1 GHz) was obtained.
Over z), an efficiency of 64% or more and a cross polarization characteristic of 25 dB or more were obtained. The conductor element 6 and the power supply probe 5
Although a was formed on the same surface of the same substrate, the same effect as described above was obtained when it was formed on both surfaces of the substrate. In other words, it can be regarded as the same plane if the thickness of the substrate is about the same.

(Embodiment 2) Conductive element 6 in Embodiment 1
Is arranged so as to sandwich the power supply probe 5a, but in this embodiment, as shown in FIG. 4, a pair of conductor elements (a long side having a length of 9 mm and a short side having a length of 2 mm) are separated by 0.5 mm on both sides of the power supply probe 5a. ) 6a and 6b are arranged.

In this embodiment, characteristics similar to those of the first embodiment were obtained. (Embodiment 3) Although the conductor elements in the above-described embodiment 2 are arranged so as to sandwich a pair of conductor elements 6a and 6b arranged on both sides of the power supply probe 5a, in the present embodiment, as shown in FIG. The conductor element (rectangular rectangle having a long side of 9 mm and a short side of 2 mm) 6b is arranged at a distance of 0.5 mm to one side (right side).

In this embodiment, characteristics similar to those of the first embodiment were obtained. (Embodiment 4) In the first embodiment, the radiation circuit board 3 having the aperture 4 as a radiating element by punching a square hole into a metal plate.
However, in this embodiment, the diameter is 1 as shown in FIG.
A radiating circuit board 3 is used in which a plurality of 5 mm circular holes are punched into a metal plate and each of the holes is an aperture 4.

In this embodiment, characteristics similar to those of the first embodiment were obtained. Fifth Embodiment In the fourth embodiment, the circular aperture 4 is provided as a radiating element of the radiating circuit board 3, but in the fifth embodiment, as shown in FIG. A notch communicating with the hole is provided at the edge of the hole that is at 45 degrees to the extension direction of 5a, and the aperture 4 is configured by the hole formed by the notch and the circular hole.

In this embodiment, 11.7 to 12.0 GHz
It was confirmed that a good circularly polarized antenna could be obtained in the above band. In addition, as shown in FIG. 8, instead of the notch, a projection projecting into a circular hole may be provided to form the aperture 4 with a hole formed at the inner peripheral edge. As shown in FIG. 9, a pair of squares may be formed. The aperture 4 may be constituted by a hole formed by a combination of a square and a rectangle inclined at 45 degrees by forming a notch at the diagonal portion, and a pair of diagonal holes are formed in the square hole as shown in FIG. The aperture 4 may be constituted by a hole formed on the inner peripheral edge of the projection by projecting the projection inside. When these apertures 4 were used, the same effects as those of the above embodiments were obtained. The power supply probe 5a and the conductor element 6
May be in any combination with the shapes of FIGS. 4 and 5,
Needless to say, this case has the same effect.

In the first embodiment, the radiation circuit board 3 is formed by punching an aperture 4 on a metal plate made of an aluminum plate. However, the aperture 4 is formed by using a copper foil portion of a commercially available flexible substrate as a conductive plate. The same performance as that of Example 1 was obtained by using the radiation circuit board 3 formed by etching. Of course, it goes without saying that the radiation circuit board 3 can be employed in the configurations of the second to fifth embodiments.

[0023]

According to the present invention, a ground conductor plate, a feeder circuit board, and a radiating circuit board are sequentially laminated so as to be separated from each other by a dielectric, and a radiating element formed of an aperture is formed on the radiating circuit board. In the planar antenna in which a feed probe that is electromagnetically coupled to the aperture is formed, a conductor element is arranged in the vicinity of the same plane as the feed probe in a non-contact manner. blanking plate it is possible to employ the fabrication of these radiating circuits plate are those can be reduced in significant cost,
Moreover, in addition to the electromagnetic coupling between the power supply probe and the aperture, resonance occurs between the conductor element and the aperture provided in the vicinity of the same plane as the power supply probe, and the band broadens, and the cross polarization characteristic is broadened. There is an effect that it can be secured over the whole area.

According to a seventh aspect of the present invention, in the first aspect of the present invention, the radiating circuit board is constituted by a metal plate having an aperture formed by punching, so that the radiating circuit board can have rigidity. Therefore, there is an effect that the accuracy of the interval between the ground conductor, the feed circuit board, and the radiation circuit board is improved, and variation in antenna performance is extremely reduced.

[Brief description of the drawings]

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

FIG. 2 is a partially omitted cross-sectional view of the first embodiment of the present invention.

FIG. 3 is a top view of a main part of the radiation circuit board according to the first embodiment of the present invention, a part of which is omitted.

FIG. 4 is a top view of a main part of a radiation circuit board with a part omitted in Embodiment 2 of the present invention.

FIG. 5 is a top view of a main part of a radiation circuit board with a part omitted in a third embodiment of the present invention.

FIG. 6 is a top view of a main part of a radiating circuit board partially omitted in Embodiment 4 of the present invention.

FIG. 7 is a top view of a main part of a radiating circuit board partially omitted in Embodiment 5 of the present invention.

FIG. 8 is a top view of a main part of a radiation circuit board with a part omitted in a sixth embodiment of the present invention.

FIG. 9 is a top view of a main part of a radiation circuit board partially omitted in Embodiment 7 of the present invention.

FIG. 10 is a top view of a main part of a radiation circuit board with a part omitted in Embodiment 8 of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ground conductor board 2 Feeding circuit board 3 Radiation circuit board 4 Aperture 5a Feeding probe 6 Conductive element

Continuation of front page (56) References JP-A-2-252304 (JP, A) JP-A-57-188106 (JP, A) JP-A-2-230804 (JP, A) JP-A-3-9602 (JP) JP-A-59-122203 (JP, A) JP-A-55-130203 (JP, A) US Patent 4,926,189 (US, A) US Patent 4,197,544 (US, A) US Patent 4,921,311 (US, A) ( 58) Field surveyed (Int.Cl. ⁷ , DB name) H01Q 13/08-13/10

Claims (7)

(57) [Claims] A ground conductor plate, a feeder circuit board, and a radiation circuit board are sequentially laminated so as to be separated from each other by a dielectric, a radiating element including an aperture is formed on the radiation circuit board, and the aperture is provided on the feeder circuit board. in the planar antenna to form a feed probe to electromagnetically coupled to the feed probe and coplanar
A planar antenna, wherein a conductor element is arranged in a non-contact manner near the upper part . 2. The planar antenna according to claim 1, wherein the aperture has a square or circular hole. 3. The method according to claim 1, wherein the aperture has a shape of a square or a circular hole, and the aperture extends in the direction in which the tip of the probe extends.
2. The planar antenna according to claim 1, wherein a notch continuous to the outside of the hole or a projection protruding into the hole is provided at a hole edge of the aperture located in the 5-degree direction. 4. The planar antenna according to claim 1, wherein a pair of rectangular conductor elements are provided on the same plane with respect to the power supply probe of the power supply circuit board and on both sides of the power supply probe with a fixed distance therebetween. 5. The planar antenna according to claim 1, wherein a rectangular conductive element is provided on one side of the power supply circuit board on the same plane with respect to the power supply probe and is separated by a predetermined distance. 6. A power supply probe of a power supply circuit board, wherein a pair of rectangular conductor elements are provided on both sides of the power supply probe at a predetermined interval on the same plane and both conductor elements are partially coupled. The planar antenna as described. 7. The planar antenna according to claim 1, wherein the radiation circuit board is constituted by a metal plate formed by punching an aperture.