JPH04369104A - Strip line feeding type plane antenna - Google Patents

Abstract

PURPOSE:To improve the antenna characteristic by allowing not only a radiation element 9 but also a slot 33 to receive a microwave so as to obtain a desired feeding distribution on a major side 2. CONSTITUTION:A dielectric board 1 is inserted between a 1st ground conductor 3 and a 2nd ground conductor 5. A radiation element 9, a feeder 11 and microwave converters 7a-7d are formed on a dielectric board 1. Each of the microwave converters 7a-7d is provided with a slot 33.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] This invention relates to a strip line fed planar antenna, and in particular to a micro antenna that converts the transmission mode of a feed line to the transmission mode of a waveguide or the transmission mode of a waveguide to the transmission mode of a feed line. The present invention relates to a stripline-fed planar antenna equipped with a wave converter.

0002

2. Description of the Related Art In recent years, with the development of satellite communication technology, satellite broadcasting using geostationary satellites is being put into practical use in earnest, and direct satellite broadcast receiving antenna systems are attracting attention. Conventionally, parabolic antennas have been mainly used as antennas for direct satellite broadcast receiving antenna systems.

However, this parabolic antenna has disadvantages in that it is greatly affected by snow accumulation, and the structure of the mounting portion is complex and requires great strength. For this reason, a shift is being made to planar antennas. This is because the planar antenna is thin and flat, so it has excellent snow accumulation resistance and wind pressure resistance.

FIG. 6 is a perspective view of a conventional planar antenna. The planar antenna includes a dielectric substrate 1, a first ground conductor 3,
It has a structure in which second ground conductors 5 are laminated.

A large number of radiating elements 9 are provided on the main surface 2 of the dielectric substrate 1 for receiving microwaves. Furthermore, a feed line 11 electrically connected to the radiating element 9 is provided on the main surface 2 . The microwaves received by the radiating element 9 are propagated to the feed line 11. The second ground conductor 5 is arranged on the main surface 2, and a radiation hole 13 is formed at the position where the radiation element 9 is formed.

A microwave converter 7 is provided at the center of the planar antenna for converting the transmission mode of the feed line 11 to the transmission mode of a waveguide (not shown). By means of the microwave converter 7, the microwave signal propagating in the feed line 11 is successfully propagated into the waveguide.

A dielectric spacer 15 is provided between the dielectric substrate 1 and the first ground conductor 3.
A dielectric spacer 17 is provided between the ground conductor 5 and the ground conductor 5 . In this way, the dielectric substrate 1 on which the radiating element 9 and the feed line 11 are formed is connected to the first ground conductor 3 and the second ground conductor 5.
By sandwiching the antenna, a triplate line-fed planar antenna is constructed.

FIG. 7 shows the microwave converter 7 shown in FIG.
FIG. The detailed structure of the microwave converter 7 will be explained using FIG. 7. A metal pattern probe 23 is provided on the main surface 2 of the dielectric substrate 1 to efficiently convert the transmission mode. The metal pattern probe 23 is electrically connected to the feeder line 11 , and the microwaves received by the radiating element 9 are collected on the metal pattern probe 23 . On the main surface 2, there is a waveguide termination section 1.
9 is arranged so that the waveguide end portion 19 and the metal pattern probe 23 do not come into contact with each other.
A notch 27 is provided in the. The second ground conductor 5 is provided with an opening 24 , and the waveguide termination portion 19 is arranged to protrude from the opening 24 .

A waveguide 21 is arranged below the first ground conductor 3, and a conductor spacer 25 is arranged between the dielectric substrate 1 and the first ground conductor 3. Conductor spacer 25
This is to prevent the microwave signal propagated from the waveguide terminal portion 19 to the waveguide 21 from leaking between the dielectric substrate 1 and the first ground conductor 3. Conductor spacer 25
A notch 29 is provided in the metal pattern probe 23 so as not to contact it. Each of the above components is fixed with screws 31.

With this configuration, the microwave signal received by the radiating element 9 and propagated from the feed line 11 to the metal pattern probe 23 is propagated to the waveguide 20.

[0011]

[Problems to be Solved by the Invention] As shown in FIG. 6, in the conventional planar antenna, since a microwave converter 7 is provided, there is radiation in the area of the main surface 2 where the microwave converter 7 is provided. Element 9 could not be provided. Therefore, it was not possible to obtain a desired feeding distribution of microwave phase, amplitude, etc. on the main surface 2 (antenna aperture surface) of the dielectric substrate 1. Since it was not possible to make the power feeding distribution a desired distribution, it was not possible to make the values of sidelobe level, efficiency, gain, axial ratio, etc. satisfactory. It is conceivable to provide the microwave converter 7 at the end of the antenna so that the feed distribution at the antenna aperture can be the desired distribution, but this would complicate the feed line and cause the micro wave in the triplate line to become complicated. The loss of the wave signal increases and the efficiency of the antenna decreases.

The present invention has been made to solve the problems of the conventional art, and an object of the present invention is to provide a stripline feeding type planar antenna that can obtain a desired feeding distribution.

[0013]

[Means for Solving the Problems] A stripline-fed planar antenna according to the present invention includes a dielectric substrate having a main surface, and a plurality of first antennas provided on the main surface for transmitting or receiving microwaves. A radiating element, a feed line electrically connected to the first radiating element, a waveguide through which microwave transmission is performed, and a waveguide provided on the main surface to change the transmission mode of the feed line to the transmission mode of the waveguide. It includes a microwave converter that converts the transmission mode of a wave path to a transmission mode of a feeder line, and a second radiating element that is provided in the microwave converter and that transmits or receives microwaves.

[0014]

[Operation] Conventionally, microwaves were not transmitted or received from the area where the microwave converter was installed, so it was not possible to achieve the desired microwave feeding distribution at the antenna aperture, but the strip according to the present invention In a line-fed planar antenna, the microwave converter is provided with a second radiating element that transmits or receives microwaves, so microwaves are also transmitted or received from the area where the microwave converter is installed. Therefore, it becomes possible to obtain a desired power supply distribution.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a perspective view of a first embodiment of a stripline-fed planar antenna according to the present invention. This antenna is an active antenna. An active antenna is an antenna that has a low-noise amplifier built into it to reduce noise. A large number of radiating elements 9 made of a conductor are formed on the main surface of a dielectric substrate 1 made of polyester. A power supply line 11 made of a conductor is also formed on the main surface 2.
The feed line 11 and the radiation element 9 are electrically connected. A second ground conductor 5 made of an electrical conductor is arranged on the main surface 2. A radiation port 13 is provided in a region of the second ground conductor 5 located above the radiation element 9 .

On the main surface 2, microwave converters 7a,
7b, 7c, and 7d are provided. The microwaves received by the radiating elements 9 (that is, 14) in the area indicated by A are synthesized and sent to the waveguide 21 via the microwave converter 7a.
is transmitted to an active element (not shown), that is, a low noise amplifier. Microwave converters 7b, 7c,
7d also transmit the microwave signals from the 14 radiating elements 9 to the active elements.

Microwave converters 7a, 7b, 7c, 7d
slots 33 each serving as a second radiating element.
There are two. It is well known that the slot 33 operates as an antenna (for example, Ultra High Frequency Circuit, co-authored by Seiyasu Itakura and Nobuaki Kumagai, Ohmsha).

Microwave converters 7a, 7 on main surface 2
Although the radiating element 9 cannot be provided in the area where the antennas b, 7c, and 7d are provided, since the slot 33 is provided, a feeding distribution similar to that of a 64-element array antenna can be obtained. Note that dielectric spacers 15 made of foamed polyolefin are provided between the dielectric substrate 1 and the first ground conductor 3 and between the dielectric substrate 1 and the second ground conductor 5, respectively.
, 17 are arranged.

FIG. 2 is a perspective view of the microwave converter 7a, and FIG. 3 is an exploded view thereof. Only the differences from FIG. 7 will be explained below. Two slots 33 are provided in the short surface 20 of the waveguide termination portion 19 . The microwave that has arrived at the waveguide end portion 19 passes through the slot 33 and is guided to the waveguide 21 . Therefore, the radiating element 9
It is combined with the microwave transmitted through the feed line 11 → metal pattern probe 23 and transmitted through the waveguide 21. Therefore, even if the radiating element 9 is not provided at the position where the microwave converter 7a is formed, it is possible to make the antenna aperture surface have an equal amplitude distribution (that is, the feeding distribution to each radiating element 9 is the same). .

[0020] By adjusting the number of installed slots 33, shape, formation position, size, distance from metal pattern probe 23 to short surface 20, etc., the type of microwave to be received, electric field strength, etc. can be set as appropriate. can do.

The second ground conductor 5, the waveguide termination 19, the dielectric substrate 1, the conductor spacer 25, and the first ground conductor 3 are fixed with screws 32, and the first ground conductor 3 and the waveguide 21 are fixed with screws 32. It is fixed by 31.

FIG. 4 is a perspective view of a microwave converter included in a second embodiment of the strip line fed planar antenna according to the present invention. A dielectric substrate 37 is provided on the waveguide terminal portion 19, and two patch antennas 35 are formed on the dielectric substrate 37. Second
In the embodiment, a patch antenna 35 serves as the second radiating element. Since the patch antenna 35 and the slot 33 are electromagnetically coupled, the microwaves received by the patch antenna 35 pass through the slot 33 and end at the waveguide end 19.
Powered by In the second embodiment, in addition to the shape, formation position, size, etc. of the slot 33, the dielectric constant, thickness, etc. of the dielectric substrate 37, and the shape, size, etc. of the patch antenna 35 are adjusted to obtain the desired shape. Can receive microwaves. In particular, when the patch antenna is a single-point-fed circularly polarized wave antenna, it is possible to receive circularly polarized waves even if there is only one slot by changing the shape of the patch antenna.

FIG. 5 is a perspective view of a microwave converter included in a third embodiment of the stripline fed planar antenna according to the present invention. In the third embodiment, similarly to the second embodiment, a patch antenna 35 formed on a dielectric substrate 37 provided on the waveguide terminal portion 19 functions as a second radiating element. However, power is supplied to the waveguide not by the slot but by a probe 39 made of a conductor inserted into the waveguide from the short surface 20.

[0024] When the resonant frequency of the slot provided at the end of the waveguide is close to the cutoff frequency of the waveguide, in other words, depending on the transmission mode, the slot becomes large and cannot be provided on the short surface. Even in such a case, the second radiating element can be easily provided according to the third embodiment.

In the first, second, and third embodiments, the slot 33 and the patch antenna 35 are provided on the short surface 20 of the waveguide termination portion 19, but the side surface (E surface) of the waveguide termination portion 19 is provided on the short surface 20 of the waveguide termination portion 19. or H-plane).

In the first, second and third embodiments, the radiating element 9 and the feed line 11 are provided on one dielectric substrate, but the dielectric substrate on which the radiating element 9 is provided and the feed line 11 are The dielectric substrate provided may be separate.

In the first, second, and third embodiments, the case where microwaves are received has been described, but the case where microwaves are transmitted may also be used.

Further, the present invention can be applied to any polarized wave such as linearly polarized wave or circularly polarized wave, and can be applied to any feed distribution, and can be applied to any type of radiating element 9.

[0029]

Effects of the Invention In the strip line fed planar antenna according to the present invention, it is possible to obtain a desired feeding distribution, so that antenna characteristics such as side lobe level, efficiency, gain, and axial ratio can be improved. In particular, the present invention is particularly effective for planar antennas such as active antennas that have a large number of microwave converters and small planar antennas that have few radiating elements.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a first embodiment of a stripline-fed planar antenna according to the present invention.

FIG. 2 is a perspective view of a microwave converter included in a first embodiment of the stripline-fed planar antenna according to the present invention.

FIG. 3 is an exploded perspective view of the microwave converter shown in FIG. 2;

FIG. 4 is a perspective view of a micro-transducer included in a second embodiment of the stripline-fed planar antenna according to the present invention.

FIG. 5 is a perspective view of a microwave converter included in a third embodiment of the stripline-fed planar antenna according to the present invention.

FIG. 6 is a perspective view of a conventional stripline-fed planar antenna.

FIG. 7 is an exploded perspective view of a microwave converter included in a conventional stripline-fed planar antenna.

[Explanation of symbols] 1 Dielectric substrate 2 Main surface 3 First ground conductor 5 Second ground conductor 7 Microwave converter 9 Radiation element 11 Power supply line 21 Waveguide 33 slot 35 Patch antenna

Claims (1)

[Claims] 1. A dielectric substrate having a main surface, a plurality of first radiating elements provided on the main surface for transmitting or receiving microwaves, and electrically connected to the first radiating elements. a feed line, a waveguide through which microwave transmission is performed, and a waveguide provided on the main surface, the transmission mode of the feed line being set to the transmission mode of the waveguide, or the transmission mode of the waveguide being set to the transmission mode of the feed line. A stripline-fed planar antenna comprising: a microwave converter for converting microwaves into microwaves; and a second radiating element provided in the microwave converter for transmitting or receiving microwaves.