JP3076440B2 - 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 for receiving linearly polarized radio waves represented by a communication satellite.

[0002]

2. Description of the Related Art Conventional planar antennas for receiving broadcast satellites have been proposed in which a strip line is formed by bending a strip line in a crank shape, or a flat antenna 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 power supply circuit is large, and it is difficult to improve the efficiency efficiently.

Therefore, a triplate-type planar antenna comprising a ground conductor plate, a feed circuit plate, and a radiation circuit plate has been developed for high efficiency and wide band, and has a reception performance comparable to that of a parabolic antenna.

However, in order to support communication satellites, it is necessary to develop antennas that can handle two types of polarization, horizontal and vertical, and also to prevent interference from adjacent satellites.

Further, since the antenna is an array antenna, side lobes are generated, and interference from an adjacent satellite cannot be ignored.

[0007]

In view of the above, there has been proposed a planar antenna in which two types of feeding circuits and a radiation circuit are sequentially laminated as shown in US Pat. No. 4,929,959. As the number of devices increases, there are problems such as an increase in cost and a large variation in performance.

Further, since the antenna is an array antenna, side lobes are generated, and interference from an adjacent satellite cannot be ignored.

[0009] The present invention has been made in view of the above problems, while suppressing a decrease in gain and it is an object of elevation with respect to the satellite, it is extremely small occurs in the horizontal direction of the side lobe, and an antenna An object is to provide a planar antenna with improved efficiency .

[0010]

According to a first aspect of the present invention, there is provided a planar antenna comprising: a ground conductor;
A first power supply circuit, a first radiation circuit in which a plurality of radiation elements are arranged, a second power supply circuit, and a second radiation circuit in which a plurality of radiation elements are arranged are sequentially separated via a dielectric layer. In a planar antenna in which a first power supply circuit and a first radiation circuit are stacked and arranged so as to generate orthogonal polarization with respect to a second power supply circuit and a second power supply circuit, The arrangement direction of each radiating element of the two radiating circuits is inclined by approximately 45 ° with respect to the axis in the horizontal direction (the horizontal direction indicates a direction that is the same as or orthogonal to the direction of the polarization to be transmitted and received). The power supply probes of the first and second power supply circuits that are electromagnetically coupled to the radiation elements of the radiation circuit are formed so as to be parallel to the horizontal axis in one power supply circuit, and to be parallel in the other power supply circuit. It is formed so as to be perpendicular to the horizontal direction, and the power supply Orthogonally arranged blanking, the second power supply
Connect the conductor element to the power supply probe near the power supply probe of the circuit.
Is a non-contact arrangement .

[0011]

According to the planar antenna of the present invention, the radiating elements of the first and second radiating circuits are arranged at an angle of about 45 ° with respect to the horizontal axis, so that the radiating elements are arranged side by side in the radiating element arranging direction. Even if lobes are generated, no side lobes are generated in the elevation and azimuth directions with respect to the satellite, interference by adjacent satellites can be extremely reduced, and the power supply probe electromagnetically coupled to each radiating element is described above. Since the first and second power supply circuits extend from the first and second power supply circuits so as to be parallel or perpendicular to the horizontal axis, a decrease in gain can be suppressed, and a gain that is almost the same as that of the related art can be secured. A conductor near the power supply probe of the second power supply circuit;
By arranging the element in non-contact with the feeding probe,
Antenna efficiency can be further improved .

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Before describing the embodiments of the present invention,
A planar antenna to which the present invention is applied will be described.

[0013] Figure 1, shown in FIG. 2, the ground conductor plate 1 planar antenna constituting each circuit layer, a first feeder circuit board 2, the first radiating circuit plate 3, the second power supply circuit board 4, the The two radiating circuit boards 5 are sequentially laminated so as to be separated from each other by a dielectric 6 made of a foamed plastic sheet. In this case , the space between the plates 1 to 5 may be formed as a space layer by using air for the dielectric 6.

Second radiation circuit board 5 located at the top
Is made of a metal plate such as aluminum having a thickness of, for example, 0.4 mm, and an aperture 7 having a circular hole having a diameter of, for example, 16 mm is used as a radiating element. In this embodiment, the apertures 7 are arranged in 16 rows and 16 columns at intervals of 23 mm. It is stamped and formed. The second feeder circuit board 4, which is arranged below the second radiating circuit board 5 with a certain distance therebetween, is made of a laminate in which a metal conductor is laminated on a dielectric film made of a plastic film, and the metal conductor is etched. A power supply probe 8a which forms a pattern of the power supply circuit 8 and is electromagnetically coupled to each aperture 7 of the second radiation circuit board 5
Are formed so as to extend from the power supply line of the power supply circuit 8 so as to be inclined by 45 ° with respect to the arrangement direction of the apertures 7.

The first radiating circuit board 3, which is arranged below the second feeding circuit board 4 and is separated by a predetermined distance, is, for example, 0.4 m.
The radiating element 9 comprises a pair of semicircular holes formed on both sides of a metal part having a width of 3 mm and including the metal part and forming a circle having a diameter of 15 mm. The aperture 9 is formed by punching 16 rows and 16 columns at 23 mm intervals in the same manner as the second radiating circuit board 5.

The first power supply circuit board 2, which is arranged below the first radiating circuit board 3 and is separated from the first radiating circuit board 3 by a predetermined distance, has a dielectric film made of a plastic film and a metal conductor like the first power supply circuit board 4. And a metal conductor is etched to form a pattern of the power supply circuit 10, and each aperture 9 of the first radiating circuit board 3 is formed.
The power supply probe 10a that is electromagnetically coupled to the power supply circuit 10 is tilted at 45 ° with respect to the arrangement direction of the apertures 9 and is orthogonal to the power supply probe 8 of the second power supply circuit board 4. It is extended from the electric wire.

The ground conductor plate 1 which is disposed below the first power supply circuit board 2 and is spaced apart from the first power supply circuit board 2 by a fixed distance is made of a metal plate such as a commercially available aluminum plate having a thickness of 2 mm. As described above, the ground conductor plate 1, the first feed circuit board 2, the first radiating circuit board 3, the second feed circuit board 4, and the second radiating circuit board 5 are connected via the dielectric 4. When laminated, as shown in FIG.
In the projection of the aperture 7 of the lower second feeding circuit board 4
The power supply probe 8a, the aperture 9 of the first radiation circuit board 3, and the power supply probe 10a of the first power supply circuit board 2 are respectively arranged, and the power supply probe 8a and the power supply probe 10a are arranged orthogonally.

FIG. 3 shows the antenna thus constructed.
As shown in FIG. 4, the power supply probe 8a of the power supply circuit board 4 is perpendicular to the horizontal axis so as to correspond to vertical polarization.
Further, the power supply probe 10a of the power supply circuit board 2 is set so as to be parallel to the horizontal axis so as to correspond to horizontal polarization.
If the arrangement is rotated by 5 °, a dual-type planar antenna corresponding to vertical polarization and horizontal polarization is completed. At this time, the arrangement direction of the apertures 7 of the second radiating circuit board 3 and the apertures 9 of the first radiating circuit board 5 is horizontal (the horizontal direction is the direction equal to or orthogonal to the direction of the polarization to be transmitted and received). (Shown) is inclined by 45 °. The 3 mm metal portion passing through the center of the aperture 9 is just the power supply probe 10a of the first power supply circuit board 2 as shown in FIG.
Orthogonal to.

When the reception characteristics were measured using the planar antenna configured as described above, two horizontal and vertical directions were measured.
It can be confirmed that various types of linearly polarized waves can be received efficiently,
When each VSWR, gain, and cross polarization characteristics were measured, a wide band of 11.5 to 12.5 GHz (1 GHz) was obtained.
Over 64%, it was confirmed that an efficiency of 64% or more and a cross polarization characteristic of 25 dB or more were obtained.

When a side lobe pattern inclined at 45 ° with respect to the arrangement direction of the apertures 7 and 9 was measured, the side lobes in the elevation and azimuth directions of the satellite were suppressed to approximately -25 dB or less. I understood that.

The aperture 9 of the above-mentioned first radiation circuit board 3
As shown in FIGS. 5 (a) to 5 (d),
Aperture 9a consisting of a pair of arc-shaped holes or one
Aperture 9b consisting of a circular hole, center and upper and lower portions
Aperture consists of three holes and the entire shape is form a circle
9c, further comprising two upper and lower holes, a portion sandwiching these holes
The shape of the metal is approximately circular in the center and has protruding parts in both sides.
And the whole shape including the above two holes forms a square
Aperture 9d or the like may be used.

In this case. Any shape of aperture 9a ~
Using 9d, the satellite elevation and azimuth
Drobe is suppressed to approximately -25dB or less, and horizontal
Efficient reception of two types of linearly polarized waves, vertical and vertical
And each VSWR, gain, and cross polarization characteristics are measured.
As a result, a wide band of 11.5-12.2 GHz (7
00MHz), over 64% efficiency and over 25dB
It was confirmed that the above cross polarization characteristics were obtained.

Further, the first and second radiation circuit boards 3 and 5 are
Apertures 9 and 7 are stamped and formed on a minium plate
However, using a commercially available flexible printed circuit board,
The apertures 9 and 7 by etching
First and second radiation circuit boards formed separately may be used.
In this case, the same antenna performance as described above can be obtained.

As described above, the configuration of the above planar antenna is used.
The elevation angle with respect to the satellite
Plane with extremely small horizontal and horizontal side lobes
An antenna can be realized.

Although the present invention suppresses such a decrease in gain,
The elevation and horizontal side lobes of the satellite
Further increase antenna efficiency for planar antennas with extremely low generation
It was done in order to improve, the example is as follows
explain. (Embodiment 1) In this embodiment, the above-described planar antenna is used.
The overall configuration is shown in FIGS.
The configuration that is the gist of the present invention will be described.

The feature of this embodiment is that the second power supply circuit board 4
FIGS. 5A to 5F show the vicinity of the feeding probe 8a.
Conductive element (parastic element) 11
Are provided in a non- contact manner.

Thus, the planar antenna of this embodiment can
Side lobes in elevation and azimuth directions are approximately -25 dB
2 types, horizontal and vertical
Can be received efficiently,
Measured VSWR, gain and cross polarization characteristics of
11.5 to 12.2 GHz broadband (700 MHz)
> 70% efficiency and> 25 dB cross polarization over
It was confirmed that the characteristics were obtained.

[0028]

According to the present invention, since the arrangement direction of the radiating elements of the first and second radiating circuit boards is inclined at about 45 ° with respect to the horizontal axis, side lobes are generated in the arranging direction of the radiating elements. However, no side lobe is generated in the elevation direction and the azimuth direction with respect to the satellite, so that interference by adjacent satellites can be extremely reduced, and the first and second electromagnetically coupled to each radiating element. since feed probe feeding circuit are then extended from the feed circuit so as to be perpendicular or horizontal to the horizontal axis, it is possible to suppress the reduction in gain, that conventionally almost unchanged gain is obtained Rights
In the planar antenna, a power supply probe of the second power supply circuit is provided.
A conductor element is placed in the vicinity of the probe and is not in contact with the power supply probe
By doing so, the antenna efficiency can be further increased
There is an effect that a flat antenna can be realized .

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a planar antenna with a part omitted.

FIG. 2 is a cross-sectional view with a part omitted from the above .

FIG. 3 is an enlarged top view partially omitted from the above .

FIG. 4 is an enlarged top view of the essential parts of the above, with some parts omitted;

FIG. 5 is an example of an aperture shape of a first radiation circuit board of the above .
FIG.

FIG. 6 shows a conductor element of a second power supply circuit board according to an embodiment of the present invention .
It is an explanatory view of a child arrangement example.

[Description of Signs] 4 Second power supply circuit board 8a Power supply probe 11 Conductive element

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) H01Q 3/00-3/46 H01Q 21/00-21/30 H01Q 23/00 H01Q 25/00-25/04

Claims (1)

(57) [Claims] 1. A grounding conductor, a first feeding circuit, a first radiating circuit in which a plurality of radiating elements are arranged, a second feeding circuit,
A second radiating circuit in which a plurality of radiating elements are arranged is sequentially stacked and separated via a dielectric layer, and a first feeding circuit and a first radiating circuit are connected to each other by a second feeding circuit and a second feeding circuit. And the radiating elements of the first and second radiating circuits are arranged at an angle of approximately 45 ° with respect to the horizontal axis in the planar antenna arranged so as to generate orthogonal polarization with respect to each other. The power supply probes of the first and second power supply circuits, which are electromagnetically coupled to the radiating elements of the circuit, are formed so as to be parallel to the horizontal axis in one power supply circuit and to the power supply probe in the other power supply circuit. The second power supply circuit is formed so as to be perpendicular to the horizontal direction and the power supply probes of both power supply circuits are arranged orthogonally.
In the vicinity of the power supply probe, connect the conductive element with the power supply probe.
Is a non-contact planar antenna.