JPH0257002A - Plane antenna - Google Patents

Abstract

PURPOSE:To reduce feeding loss by providing a groove in a conductor, obtaining a square external conductor and forming a suspended line together with a lead wire on a dielectric. CONSTITUTION:A radio wave to be inputted from a feeding port 10 progagates the suspended line, which is composed of grooves 6a and 6b and an internal conductor 7, and feeding is executed to a patch antenna 9 which is provided in the internal part of holes 4 and 5. The wave is radiated from the patch antenna 9 through the hole 4 to a space. A line from the feeding port 10 to the patch antenna 9 goes to be the suspended line to be composed of a dielectric substrate 3, for which the internal conductor to be composed of a metallic film is provided by etching or printing, etc., and conductor boards 1 and 2 with the grooves 6a and 6b, which are provided in the both sides of the dielectric substrate 3, on the thin film dielectric substrate 3. Thus, transmission can be executed with the low loss.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a flat antenna used for satellite communications in the microwave band or millimeter wave band, terrestrial-to-L communication, direct reception of satellite broadcasting, etc. be.

[Conventional technology]

FIG. 3 is a diagram showing the configuration of a conventional planar antenna shown in, for example, Japanese Patent Publication No. 62-23209, with FIG. 3(a) being a front view and FIG. FIG. In these figures, (1) is "two-side conductor,
(2) is the lower conductor, (3) is the thin film substrate, (4) is the through hole provided in the upper conductor (1), and (5) is the bottom hole provided in the lower conductor (2). A certain hole (6) is a hollow part of the suspended line, (7) is an inner conductor of the suspended line, and (8) is an excitation probe. Here, a suspended line is one in which a dielectric substrate with a strip conductor is supported by both side walls of a rectangular outer conductor or one side wall groove.Since it is surrounded by a rectangular outer conductor, there is no radiation of electromagnetic waves, and there is no transmission loss. It has the characteristic that there are few

Since the radiating element of the conventional planar antenna is configured as described above, the holes (4) and (5) are made to act as circular waveguides, and (8) is made to act as an excitation probe, thereby allowing the radiation from the suspended line to be made. The radio waves supplied with power,
The radio waves are radiated from the circular waveguide described in 1-1, which serves as a radiating element, or the radio waves incident on the circular waveguide described in 1-1 are guided to the suspended line.

Figure 4 shows the conventional 511-
4(a) is a front view, and FIG. 4(b) is a sectional view taken along line A-Δ. In these figures, (1) is the side conductor, (2) is the bottom conductor,
(3) is a thin film substrate, (6a) and (6b) are air layers,
(7) is the inner conductor of the blade Spendenoto line, and (9) is the patch antenna.

Since the radiation element of the conventional planar antenna is configured as described above, the radio waves fed by the pentagonal line resonate with the patch antenna (9) and are radiated into space. In addition, the radio waves incident on the punch antenna (9) were guided to the suspended track. Note that this patch antenna (9) can transmit or receive unidirectionally polarized radio waves by providing a spark.

[Problem to be solved by the invention]

The radiating element of a conventional planar antenna as shown in Figure 3 is
It consists of a circular waveguide excited by a probe, so
It is necessary to set the distance (11) from the bottom of the circular waveguide to the probe to about one quarter of the wavelength in the guide, and furthermore, in order to efficiently radiate the radio waves in the circular waveguide into space as described in -.
Since it is necessary to gradually increase the inner diameter of the waveguide, there is a problem in that the overall thickness increases. Although actual thicknesses up to about 20 mm have been developed, it is difficult to reduce the thickness to less than this.

Next, in the radiating element of a conventional planar antenna as shown in Figure 4, since the thin film substrate is separated from the second and lower conductors, it is difficult to maintain the spacing, and it is difficult to accommodate variations in one spacing. There is a problem that the characteristics deteriorate. In addition, a hole is provided in the upper conductor near the patch antenna in order to radiate radio waves, which makes the structure vertically asymmetrical relative to the thin film substrate. Therefore, due to the asymmetric structure, some of the radio waves in the symmetrical mode that propagated on the gas pump line become radio waves in the vertically asymmetrical mode, propagating between the upper conductor and the lower conductor, and transmitting to other lines and patch antennas. There is a problem that the characteristics deteriorate when combined with moreover,
In this type, the upper conductor and lower conductor are made of flat plates, so it is a suspension bench.

1. Distance between the 10-side conductor and the lower conductor on the line (i'I)
1,) and the same spacing (h) in the patch antenna portion cannot be changed. Therefore, there is a problem in that it is difficult to design 1, 13 individually so that the gas pump line part has low loss and the patch antenna part has a wide frequency band.

This invention was made to solve the problems such as +l' and Ng, and aims to obtain a planar antenna having low loss and good radiation characteristics over a wide band.

[Means to solve the problem]

The planar antenna according to the present invention (a) is an antenna element or a dielectric antenna element in which a radiating conductor and a conducting wire are arranged on a dielectric body; (b) the antenna element is a dielectric antenna element in which a radiating conductor and a conducting wire are arranged in a dielectric body; , an opening of a predetermined size is provided from the radiation conductor to the free space.

(c) A recess of a predetermined size is provided in the other conductor sandwiching the antenna element at the same position as the above-mentioned opening.

(d) A groove of a predetermined size is provided in the conductor sandwiching the antenna element along the conducting wire placed in the dielectric (e) - Other than the openings, recesses, and grooves mentioned above, the dielectric and the conductor [Function] In this invention, the groove provided in the conductor becomes a rectangular outer conductor and forms a suspended line with the conductor on the dielectric, so that the power supply loss can be reduced. Can be done. Furthermore, since the radiation conductor is surrounded by the wall of the opening from the radiation conductor to the free space and the wall of the recess that corresponds to the opening, the radio waves do not couple with other conductors or antenna elements, and the characteristics deterioration can be prevented. Furthermore, since the size of the groove of the suspended line, which is the feed line, and the size of the opening and recess of the antenna element can be designed individually, in other words, the distance to the dielectric and the conductor can be selected separately, so the line It is possible to obtain good characteristics in the antenna element.

[Embodiments of the invention]

Fig. 1 is a diagram showing the configuration of a planar antenna which is an embodiment of the present invention, Fig. 1(a) is a front view, Fig. 1(b) (c)
) is a cross-sectional view. FIG. 2 is a perspective view of a planar antenna according to the present invention. In fig.

(1) is the upper conductor, (2) is the lower conductor, (3) is the dielectric substrate, (4) is a through hole that becomes the opening in the upper conductor (1), and (5) is the lower conductor. (2) is a hole with a bottom that becomes a recess, and (6) is for upper conductor (1) and lower conductor (2).
) groove that becomes the outer conductor of the suspended line, (7
) is the inner conductor of the suspended line, which is provided by etching etc. on the surface of the dielectric substrate (3), and (9) is the inner conductor of the suspended line, which is connected to the inner conductor (7) of the suspended line.
5) Basochi antenna that serves as a radiation conductor installed inside the
(10) is a power supply port.

In the planar antenna configured as described above, radio waves input from the feed port (10) propagate through the susubenzo-nod line consisting of the grooves (6a) (6b) and the inner conductor (7), and then propagate through the hole ( 4), (5) is fed to the Sochi antenna (9) installed inside the batch antenna (9).
) is radiated into space through the hole (4). In the case of reception, on the contrary, radio waves incident on the patch antenna (9) from space pass through the suspense-nod line to the feed port (1).
0).

In a planar antenna with such a structure, the feed port (10
) to the patch antenna (9) is the above-mentioned dielectric substrate (3) in which an inner conductor made of a metal film is provided on the surface of the thin-film dielectric substrate (3) by etching or printing, etc.
and grooves (6a) provided on both sides of the dielectric substrate (3).
Since it is a suspended line consisting of conductor plates (1) and (2) with (6b) attached, transmission can be performed with low loss. Roughly speaking, since the outer conductor of the suspended line surrounds the inner conductor (7), the radio waves that propagate unnecessarily between the upper conductor (1) and the lower conductor (2) are small, making it difficult for other lines to Since it does not interfere with the antenna or other patch antennas, deterioration in characteristics can be minimized.

Next, in the patch antenna (9), - the through hole (4) provided in the upper outer conductor (1) and the lower outer conductor (2
) is used as a grounding conductor, the notech antenna (9) resonates, and radio waves are radiated into space through the hole (4). The frequency band in which the reflected power of this patch antenna (9) is small is mainly the above-mentioned Nos.

The distance from the antenna (9) to the bottom of the hole (5) (14
), and generally speaking, the larger this distance, the wider the band. Therefore, in this case, this distance (14) can be determined according to the used frequency band, and good characteristics can be obtained within the used frequency band.Furthermore, in the case of such a structure, the hole ( 4), (
5) By making the distance (14) to the bottom of the hole (5) larger than the depth (15) of the groove (6b) in the part that converts into a line, the conversion part can be made into an almost vertically symmetrical structure. So you can.

The vertically symmetrical mode radio waves propagating on the suspended line can be efficiently transmitted to the patch antenna (9). Furthermore, a hole (4) made of metal is placed around the patch antenna (9).
, (5), the radio waves fed to the patch antenna (9) can be efficiently radiated into space through the hole (4). Also, with the above configuration, the dielectric Because it uses a body antenna element,
It is possible to make one with a thickness of 2 to 4 mm, and it is a waveguide type (2
A thinner planar antenna can be made (around 0mm).

In addition, 2 and above have explained the case of a rectangular batch antenna with single point feeding linearly polarized wave excitation as a patch antenna, or 1
Similar effects are obtained in the case of point-fed circularly polarized wave excitation, two-point fed circularly polarized wave excitation, and orthogonal two-polarized wave excitation. Furthermore, the same effect can be obtained even if the shape of the patch is circular or rectangular. In addition, we have explained the case where a metal plate is used as the conductor plate on the top side and the bottom side, or a structure in which a metalized plastic or thin metal plate is provided with grooves, irregularities and holes to form the openings and walls of the four parts. Similar Effect [Effect of the Invention] As explained in 1-1, according to the present invention, the feed line is a suspended line, so the loss can be reduced, and the patch antenna is surrounded by a metal wall. Therefore, radio waves can be efficiently radiated into space,
Furthermore, since the structure of the feed line part and the patch antenna part can be determined individually, r? The type II type can be designed with low loss, and the latter type can be designed with a wide band, and a high-performance planar antenna can be realized.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing the configuration of a planar antenna according to the present invention.
FIG. 2 is a perspective view of a planar antenna according to the present invention, and FIGS. 3 and 4 are diagrams showing the configuration of a conventional planar antenna. In the figure, (1) is the upper conductor, (2) is the lower conductor, (
3) is a dielectric substrate, (4) is a through hole, (5) is a hole with a bottom, (6) is an outer conductor, (7) is an inner conductor, (8) is a probe, and (9) is a patch. antenna, (+0) is the feeding [
It is J.

Claims (1)

[Claims] Planar antenna having the following elements (a) Dielectric antenna element having the following elements (a1) dielectric (a2) radiation conductor disposed on the dielectric (a3) disposed on the dielectric, (b) a first conductor having the following characteristics: (b1) being in contact with the surface of the dielectric on which the radiation conductor is placed; (b2) a predetermined distance from the radiation conductor to free space; (b3) a groove of a predetermined size is provided along the conducting wire; (c) a second conductor having the following characteristics; (c1) a dielectric material opposite to the first conductor; (c2) A recess of a predetermined size is provided at the same position as the opening of the first conductor. (c3) A groove of a predetermined size is provided along the conductor.