JPS61195006A - Plane antenna - Google Patents

Abstract

PURPOSE:To reduce the warp of a circuit board and to prevent the mismatching of the impedance of a plane antenna by providing protrusively a reinforcing rib in the outer periphery of a ground conductor formed on the back surface of the dielectric layer of an antenna circuit board. CONSTITUTION:The ground conductor 4 is coated on the back surface of the dielectric layer 3 of the antenna circuit board 1 comprising the plane antenna, and a microstrip line 5 made of a metallic foil is formed on the surface of the dielectric layer 3. The strip line 5 is coated with a protective film 6 to protect the strip line. The reinforcing rib 7 is protrusively provided in the outer periphery of the ground conductor 4. Then the warp of the circuit board 1 is reduced to prevent a drop in gains due to the mismatching of the impedance of the plane antenna, thereby improving gains of the plane antenna.

Description

[Detailed description of the invention] 【Technical field】

The present invention relates to a planar antenna used for microwave communication, satellite communication, etc.

[Background technology]

Conventionally, as shown in Fig. 5, a dielectric layer 3 is layered on a flat ground conductor 4, a layer of maffil is layered on top of the dielectric layer 3, and an adhesive (not shown) is interposed between these layers. They were then glued together using hot pressing to form a planar antenna. The following materials were used for these: Protective film 6...For example, polyethylene tele7
Dielectric layer 3: Low dielectric constant Teflon or polyethylene (1 mai thickness) Ground conductor 4: Aluminum plate (2+a-thickness) Microstrip line 5... Aluminum foil (20 μm thick) or copper foil (35 μm thick) such a configuration,
In the planar antenna using materials, distortion occurs due to differences in the coefficient of expansion and modulus of longitudinal elasticity between the ground conductor 4, the dielectric N3, and the protective film 6, resulting in warping, which causes the antenna's directional characteristics and in-begence matching to deteriorate. (There was a problem that the ground conductor 4, dielectric material M3, and M3) were bonded together by hot pressing, leading to a decrease in gain. At this time, the dielectric N3 in a molten state flows out from the upper surface of the ground conductor 4, and the thickness of the completed dielectric layer 3 becomes non-uniform, resulting in impedance mismatch.

[Purpose of the invention]

The present invention was made in view of the above-mentioned technical background, and its purpose is to provide a planar 7 antenna that can reduce warpage as a planar antenna and, as a result, reduce impedance mismatch. There is something to do.

[Disclosure of the invention]

In the planar antenna of the present invention, a microstrip line 5 made of metal foil is arranged on a dielectric layer 3 bonded on the surface of a ground conductor 4, and the microstrip line 5 is protected from above the microstrip line 5. The antenna circuit board 1 is formed by adhering a protective film 6 for the antenna, and reinforcing ribs 7 are protruded from the outer periphery of the ground conductor 4, thereby achieving the object of the present invention. It ends with the achievement of. That is, the strength of the planar antenna is improved by the reinforcing ribs 7 provided on the outer periphery of the ground conductor 4, and the planar antenna does not warp.
This makes it possible to ensure matching of the directional characteristics and impedance of the planar antenna. Note that if the reinforcing ribs 7 are made to protrude toward the dielectric layer 3 side, the reinforcing ribs 7
serves as a dam to prevent the dielectric layer 3 from flowing out during hot pressing, and to make the thickness of the dielectric layer 3 uniform. A ground conductor 4 according to an embodiment of the present invention will be described below in detail based on the attached drawings.
is a grounding conductor substrate for grounding and is made of a metal material, forming a plane parallel to the metal foil forming the lip line 5 to accurately reflect and transmit received microwaves. It has a role. A dielectric layer 3 made of polyethylene or the like is formed on the upper surface of the ground conductor 4. The outer peripheral edge of the ground conductor 4 is oriented L toward the dielectric layer 3.
The reinforcing ribs 7 are made to protrude from the outer periphery of the ground conductor 4, thereby improving the strength of the ground conductor 4, and thus the planar strength of the ground conductor 4 and the planar antenna. This prevents the flat antenna from warping or twisting. *Although the dielectric layer 3 is in a fluid state during hot pressing, the reinforcing ribs 7 act as a dam to prevent the dielectric layer 3 from flowing out of the ground conductor 4, and the dielectric layer-3 This makes it possible to mold to a uniform thickness. The reinforcing ribs 7 can be provided on only one side of the ground conductor 4 for reinforcement purposes, but it is preferable to provide them on two or more sides. That is, the second
A side and 0 side (2 sides), C side and 2 sides (2 sides), A side and 2 sides (2 sides), C side and mouth side (2 sides), A side, mouth side, and C side of the diagram It is preferable to provide it on the (3 sides), the A side, the mouth side, the C side, and the second side (4 sides). Then, on the dielectric layer 3, a microstrip line 5 formed in a certain pattern by a group of conductor sections made of metal foil is laminated, and on top of the microstrip line 5, a layer for protecting the microstrip line 5 is laminated. The protective film 6 is laminated with an adhesive sheet interposed between each layer to form a circuit board 1, and the antenna circuit board 1 and a converter (not shown) form a planar antenna. What is shown in FIG. 3 is the other side of the present invention, in which the end of the ground conductor 4 is bent toward the dielectric layer 3 in a U-shaped cross section, and a reinforcing rib protrudes toward the dielectric layer 3. 7 was formed. What is shown in FIG. 4 is yet another aspect of the present invention, in which the ground conductor 4
The outer peripheral end portion of the reinforcing rib 7 is bent in the direction opposite to the dielectric layer 3 in a cross-sectional shape, so that the reinforcing rib 7 protrudes toward the side opposite to the dielectric layer 3.

【Effect of the invention】

As described above, the present invention arranges a microstrip line made of metal foil on a dielectric layer bonded on the surface of a ground conductor, and provides protection for protecting the microstrip line from above the microstrip line. [The antenna circuit board is formed by adhering the film, and the reinforcing ribs are protruded from the outer periphery of the ground conductor. There are advantages in that the warpage of the antenna is reduced, the directivity is good, the impedance matching is good, and a planar antenna with high antenna gain can be obtained. In addition, if the reinforcing lip is made to protrude toward the dielectric layer side, the reinforcing lip will act as a dam to prevent the dielectric layer from flowing out during hot pressing and make the thickness of the dielectric layer uniform. It is possible.

[Brief explanation of drawings]

FIG. 1 is a sectional view showing one embodiment of the present invention, FIG. 2 is a perspective view of the same as above, FIG. 3 is a sectional view showing another example of the invention, and FIG. Cross-sectional view Figure 5 is a cross-sectional view showing a conventional example, in which 1 is an antenna circuit board, 3 is a dielectric layer, 4 is a ground conductor, 5 is a microstrip line, 6 is an insulation film, and 7 is a reinforcing lip. be. Agent Patent Attorney Ishi 1) Ai 7 Figure 1 Figure 2

Claims (1)

[Claims] (1) A microstrip line made of metal foil is placed on the dielectric layer that is adhered to the surface of the ground conductor, and a protective film is adhered on top of the microstrip line to protect the microstrip line. A planar antenna characterized by forming an antenna circuit board and having reinforcing ribs protruding from the outer periphery of a ground conductor.