JPH01180102A - Planar antenna - Google Patents

Abstract

PURPOSE:To reduce the reduction in the antenna efficiency due to the conductor loss of a radiation conductor by clipping the radiation conductor by means of two dielectric bases fixed together. CONSTITUTION:The radiation conductor 12 is formed by etching a conductor film vapor-deposited or bonded to one face 11 of the dielectric base 1 in a required shape. A face 22 at opposite side of the dielectric base 2 with a ground conductor vapordeposited onto one face with respect to the ground conductor 21 is bonded or thermally molten to the face 11 of the base 1. A current flows to a face in contact with the base 2 of the conductor 12 by an electromagnetic field with the ground conductor 21. The conductor loss is reduced by smoothing sufficiently the face. Since the conductor 12 is clipped between the bases 1, 2 even when the face is smoothed, the possibility of exfoliation from the base 2 is precluded. Since the face of the conductor 12 in contact with the base 2 is smoothed sufficiently, the deterioration in the antenna efficiency of the planar antenna due to the conductor loss of the radiation conductor is reduced.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a planar antenna, and particularly to a planar antenna having a microstrip structure.

[Conventional technology]

Conventionally, this type of planar antenna has been manufactured by etching a conductive film on one side into a desired shape out of conductive films deposited or bonded on both sides of a dielectric substrate 3, as shown in an example in FIG. The radiation conductor 4 was used as the radiation conductor, and the conductor film on the other side was used as the ground conductor 5.

Since the radiation conductor 4 is normally exposed to space, the surface of the radiation conductor 40 is coated to prevent corrosion, and
The mutual contact surfaces of the radiation conductor 4 and the dielectric substrate 3 are each formed with fine irregularities to enhance adhesive strength and prevent the radiation conductor 4 from peeling off from the dielectric substrate 3.

[Problem that the invention seeks to solve]

In the conventional planar antenna described above, the surface of the radiation conductor 4 on the dielectric substrate 3 side has a fine unevenness, so that the path length of the current flowing through this surface due to the electromagnetic field between it and the ground conductor 5 is as short as the surface. The disadvantage is that the antenna becomes longer due to the effect, and conductor loss increases, reducing antenna efficiency.

An object of the present invention is to provide a planar antenna in which antenna efficiency is less reduced due to conductor loss of a radiation conductor.

[Means for solving problems]

The planar antenna of the present invention includes a first dielectric substrate provided with a ground conductor film on one surface, a film-like radiation conductor, and the first dielectric substrate provided on one surface with the radiation conductor in between. A second dielectric substrate is fixed to a surface of the substrate opposite to the surface on which the ground conductor film is provided.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

FIG. 1 is an exploded perspective view showing one embodiment of the present invention.

A radiation conductor 12 is formed by etching a conductive film deposited or adhered onto one surface 11 of the dielectric substrate 1 into a desired shape. Dielectric substrate 2 with a ground conductor 21 deposited on one surface
The surface 22 opposite to the ground conductor 21 side is the surface 1 of the dielectric substrate 1.
1 or heat fused.

Due to the electromagnetic field between the radiation conductor 12 and the ground conductor 21, a current flows through the surface of the radiation conductor 12 that is in contact with the dielectric substrate 2.

By making this surface sufficiently smooth, conductor loss can be reduced. Even if this surface is smoothed, there is no fear that the radiation conductor 12 will peel off from the dielectric substrate 2 because it is sandwiched between the dielectric substrates 1 and 2.

The radiation conductor is placed not on the dielectric substrate 1 but on the surface 22 of the dielectric substrate 2.
Alternatively, the radiation conductor can be fabricated separately from the dielectric substrates 1 and 2. In either case, the surface of the radiation conductor on the ground conductor 21 side is made sufficiently smooth. As in the embodiment shown in FIG. 1, conductor loss can be reduced without fear of the radiation conductor coming off from the dielectric substrate 2.

〔Effect of the invention〕

As explained above, in the present invention, by sandwiching the radiation conductor between two dielectric substrates that are fixed to each other, the surface of the radiation conductor through which current flows can be made sufficiently smooth without fear of peeling off from the dielectric substrate. This has the effect of reducing the decrease in antenna efficiency due to conductor loss of the radiation conductor, and also has the effect that there is no need to coat the surface of the radiation conductor because the radiation conductor is not exposed to space.

[Brief explanation of the drawing]

FIG. 1 is an exploded perspective view showing an embodiment of the present invention, and FIG. 2 is a perspective view of an example of a conventional planar antenna. 1.2... Dielectric substrate, 12... Radiation conductor, 21... Ground conductor. Agent Patent Attorney Susumu Uchihara

Claims (1)

[Claims] A first dielectric substrate having a ground conductor film on one surface, a film-like radiation conductor, and the ground conductor film of the first dielectric substrate on one surface with the radiation conductor in between. A planar antenna characterized by comprising a second dielectric substrate fixed to a surface opposite to the surface on which the planar antenna is provided.