JPH0149205B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a microstrip array antenna made of a sandwich structure.

Generally, thin, large-diameter antenna systems include a printed slot array antenna system and a microstrip array antenna system. The former has advantages such as a wide band, but is structurally complex and difficult to manufacture, so it is not often used. On the other hand, microstrip array antennas are structurally simple and are often used as large antennas.

The basic structure of this microstrip array antenna is shown in FIG.

That is, in this microstrip array antenna, a metal radiating element 2 and a feeder line 3 connecting the radiating element 2 are adhered to one side of a substrate 1 made of a dielectric material, and the other side of the substrate 1 is coated entirely. It has a thin and light structure with a metal ground conductor 4 throughout.

FIG. 2 is a diagram showing an actual example of this antenna.

In the figure, 2 is a rectangular radiating element made of metal foil with extremely high electrical conductivity such as gold, silver, or copper, 3 is a feeder line that electrically connects the radiating element 2, and 4 is the same as the radiating element 2. A ground conductor made of metal foil with extremely high electrical conductivity; 5 a dielectric core made of a material with a low dielectric constant such as nylon, GFRP (glass fiber reinforced plastic), or polymeric foam; 6a and 6b a GFRP or The dielectric skin is made of a material with a small dielectric constant and dielectric loss, such as aramid fiber reinforced plastic, and is bonded to the dielectric core 5, and the dielectric core 5 and the dielectric skins 6a and 6b are the first The substrate 1 shown in the figure is constructed.

In this antenna, when the length of the radiating element 2 (indicated by A in Figure 2) is selected to be half the wavelength of the frequency used, electromagnetic waves resonate between the radiating element 2 and the ground conductor 4, and the radiating element 2 Radio waves leak from the tip of the
This becomes a radiation wave and operates as an antenna.

The conventional microstrip array antenna is
The structure is as described above, and the dielectric skin 6a,
The thickness of the dielectric core 5 and the thickness of the dielectric core 5 are primarily determined by electrical performance, and the materials used are also limited, so it is important to increase the capacity and size of antennas such as high-gain large-aperture antennas for use on satellites. In this process, it is difficult to ensure the rigidity of the antenna with a single antenna panel, and the deflection of the antenna panel increases, resulting in a decrease in surface accuracy, which disrupts the radiation pattern, resulting in a decrease in gain and an increase in side lobes. The drawback was that electrical performance deteriorated.

Furthermore, since the rigidity or strength of the panel is low, there is also a drawback in that it lacks reliability in terms of mechanical strength when subjected to external forces.

SUMMARY OF THE INVENTION An object of the present invention is to provide a lightweight, highly rigid microstrip array antenna with excellent electrical performance that can eliminate the above-mentioned drawbacks.

The present invention will be explained below with reference to the drawings.

FIG. 3 is a diagram showing an embodiment of a microstrip array antenna according to the present invention.

In Figure 3, from 2 to 6 are the same as in Figure 2,
7 is a reinforcing beam. This invention has a structure in which reinforcing beams 7 made of a material with high specific rigidity and specific strength, such as CFRP (carbon fiber reinforced plastic) and aramid fiber reinforced plastic, are arranged in a lattice pattern on the outside of the ground conductor 4. That is. This reinforcing beam 7 is bonded to the antenna panel by adhesive, screwing, or a combination of both, and serves to backfire the antenna panel.

In the antenna configured in this way, the reinforcing beam 7
By appropriately setting the material and shape of the antenna, it is possible to obtain an antenna with the required rigidity and weight, which prevents the antenna from bending easily and prevents deterioration in electrical performance due to lack of surface accuracy.

Furthermore, since the overall rigidity is increased, it is also possible to reduce the thickness of the dielectric skin, thereby lowering the equivalent permittivity of the antenna substrate and improving the electrical performance of the antenna.

Furthermore, the increase in rigidity also has the effect of improving reliability in terms of mechanical strength.

Although the above example shows a microstrip array antenna having a rectangular radiating element 2, it goes without saying that the present invention can be applied to a microstrip array antenna having a circular or other shaped radiating element. do not have.

As described above, the microstrip array antenna according to the present invention has a structure in which reinforcing beams are arranged in a lattice pattern on the ground conductor side. This has the effect of providing a lightweight and highly rigid antenna with excellent performance.

[Brief explanation of drawings]

FIG. 1 is a perspective view showing the basic structure of a microstrip array antenna; FIG. 2 is a partially cutaway perspective view showing an example of a conventional antenna of this type;
FIG. 3 is a perspective view showing a microstrip array antenna according to an embodiment of the present invention. In the figure, 1 is a substrate, 2 is a radiation element, 3 is a feeder line,
4 is a ground conductor, 5 is a dielectric core, 6a and 6b are dielectric skins, and 7 is a reinforcing beam.

Claims (1)

[Scope of Claims] 1. Metal foil is formed on one surface of a sandwich panel in which a dielectric skin is coated on both sides of a dielectric core to form a ground conductor, and a metal foil of an arbitrary shape is coated on the other surface. 1. A microstrip array antenna as a radiating element formed by adhesion, characterized in that the ground conductor is lined with reinforcing beams arranged in a grid pattern. 2. The microstrip array antenna according to claim 1, wherein the reinforcing beam is made of a material with high specific rigidity and specific strength, such as carbon fiber reinforced plastic or aramid fiber reinforced plastic.