JPH02141007A - Micro-strip antenna - Google Patents

Abstract

PURPOSE:To obtain input impedance characteristics over a wide band range with a simple structure by providing a parasitic conductor on the inner surface of a radome covering a radiation conductor. CONSTITUTION:Since a parasitic conductor 5 is fitted to the inner surface of a radome 7 with a bonding agent, etc., a dielectric holding body can be omitted and at the same time, the conductor 5 is faced to a radiation conductor 3 beyond an air layer or dielectric layer 4 and the conductor 5 can be made to have a circular shape. When the radiation conductor 3 is excited, the radiated field excites the parasitic conductor 5 provided on the inner surface of the radome 7 through the air layer or dielectric layer 4 and radio waves are radiated into the air. Therefore, an micro-strip antenna which can have wide-band impedance characteristics similar to those conventional antennas with a simple constitution can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the structure of a microstrip antenna having broadband characteristics.

[Conventional technology]

FIG. 6 is a cross-sectional side view showing a conventional broadband microstrip antenna, in which 1 is a dielectric plate, 2 is a ground conductor plate provided on one side of the dielectric plate 1, and 3 is a dielectric plate 1.
a radiation conductor provided on a surface opposite to the above one surface of 4;
is an air layer or a dielectric layer provided above the radiation conductor 3,
5 is a parasitic conductor placed opposite to the radiation conductor 3 with an air layer or dielectric layer 4 in between; 6 is a dielectric with the parasitic conductor 5 provided on its lower surface; 7 is a radome covering the entire surface; 8 is a radome 7
This is a fastener for fixing the dielectric plate 1 to the dielectric plate 1.

Next, the operation will be explained. When the radiation conductor 3 is excited,
The dielectric plate 1 between the radiation conductor 3 and the ground conductor plate 2 operates as a resonator, serving as a wall of air, so that radio waves are radiated into the air. Further, this radiation field excites the parasitic conductor 5 through the air layer or the dielectric layer 4, so that the parasitic conductor 5 resonates and radio waves are radiated into space. As mentioned above, in general, power is supplied only to the radiation conductor 3,
If the parasitic conductor 5 is used in addition, an antenna whose input impedance can be matched over a wide band can be obtained.

[Problem to be solved by the invention]

Since the conventional microstrip antenna is constructed as described above, the dielectric material 6 on which the parasitic conductor 5 is provided is
It is necessary to provide a radome 7 as a cover to cover the entire antenna, and a radome 7 is also necessary from a practical standpoint such as antenna protection. The structure has three or more layers including the dielectric 6 provided with the parasitic conductor 5, the radome 7, etc., resulting in a complicated structure.

Regarding this invention, for example, "Double circular microstrip antenna using honeycomb" (1985 IEICE General Conference, 711.3-80
).

The present invention has been made to solve the above-mentioned problems, and its purpose is to obtain a wideband microstrip antenna with a simple structure.

[Means to solve the problem]

In the microstrip antenna according to the present invention, a parasitic conductor is provided on the inner surface of a radome that covers a radiation conductor.

[For production]

By providing the radiation conductor on the inner surface of the radome, the microstrip antenna according to the present invention has a simple structure and can obtain wide-band input impedance characteristics.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
In the figure, parts corresponding to those in FIG. 6 are denoted by the same reference numerals, and description thereof will be omitted. In the embodiment shown in FIG. 1, as shown, a parasitic conductor 5 is provided on the inner surface of a radome 7 by adhesive or the like.

Therefore, the dielectric material 6 in FIG. The shape of the power supply conductor 5 is circular as shown in Fig. 2.The radome 7 is made of a dielectric material whose thickness is thin compared to the wavelength of the radio waves to be emitted. ing.

Next, the operation will be explained. When the radiation conductor 3 is excited,
The radiation field passes through the air layer or dielectric layer 4 to the radome 7.
A parasitic conductor 5 provided on the inner surface of the device is excited, and radio waves are radiated into space.

In the above embodiment, the shape of the parasitic conductor 5 is circular, but it may be square as shown in FIG.
It may be formed into a circular ring shape as shown in the figure or a rectangular ring shape as shown in FIG. 5, and the same effect as the above embodiment can be obtained.

〔Effect of the invention〕

As described above, according to the present invention, since the parasitic conductor is provided on the inner surface of the radome, the dielectric material conventionally used can be omitted, and the same broadband input as the conventional one can be achieved with a simple configuration. A microstrip antenna having impedance characteristics can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional side view showing a microstrip antenna according to an embodiment of the present invention, FIG. 2 is a plan view of the main part of FIG. 1, and FIGS. Main part plan view of microstrip antenna according to the embodiment, No. 6
The figure is a cross-sectional side view showing a conventional Micros IJ tube antenna. 1 is a dielectric plate, 2 is a ground conductor plate, 3 is a radiation conductor, 4 is an air layer or dielectric layer, 5 is a parasitic conductor, and 7 is a radome. In addition, the same symbols in the figures indicate the same or equivalent parts.

Claims (1)

[Claims] a dielectric plate, a ground conductor plate provided on one surface of the dielectric plate, a radiating conductor provided on a surface opposite to the one surface of the dielectric plate, and an air layer or A microstrip antenna comprising a radome provided with a dielectric layer sandwiched therebetween and covering the radiation conductor, and a parasitic conductor provided on the inner surface of the radome to face the radiation conductor.