JPS60261204A - Slot array antenna system - Google Patents

Abstract

PURPOSE:To thin a main lobe by taking an impedance matching, and also to suppress a side lobe by forming an equiphase surface of an electromagnetic wave radiated from an opening part of a reflecting plate, to a shape of a plane. CONSTITUTION:As for an electromagnetic wave radiated from a slot waveguide 1, a part of said wave advances forward, and that which has been radiated at a large angle is reflected by dielectric plates 3a, 3b and advances forward. The electromagnetic wave radiated at a large angle passes through the dielectric plates 3a, 3b, are reflected by a reflecting part 4b of a reflecting plate 4 and advances forward, and an electromanetic wave beam scarcely having a side lobe is obtained. Also, in the tip of the reflecting plate 4, an impedance matching to the outside of the reflecting plate 4 is taken by a projecting part 4a, and also a plane-shaped part of the equiphase surface is increased in the projecting part 4a, by which a rise of the side lobe advancing in other direction than the main beam is prevented.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a slot array antenna device suitable as an antenna for a marine radar, a relay device, etc., and in particular, it is equipped with a dielectric waveguide mechanism and is small and lightweight. Slots designed to
The present invention relates to an array Φ antenna device.

[Prior Art] Slotted array antenna devices are smaller and lighter than parabolic antennas and the like, so they are often used in marine radars that need to be mounted on a mast or the like. However, with only a slot waveguide, a directional beam can only be formed within a plane containing the tube axis of the slot waveguide (hereinafter referred to as the horizontal plane), and a directional beam can only be formed in a plane perpendicular to the horizontal plane (hereinafter referred to as the vertical plane). ) cannot form a directional beam in the vertical plane, so a horn is usually attached to obtain a directional beam in the vertical plane.
It is used. Therefore, even though it is not as sharp as a parabolic antenna, when trying to obtain a sharp beam, the weight increases and the aperture area increases, which has the drawback of increasing the influence of wind pressure when used outdoors. In particular, the issue of wind pressure is extremely important for marine radars used on windy seas, as this has a great effect on not only the strength of the radar itself but also the rotational drive system.

In response, the applicant has developed a slot system that is equipped with a dielectric waveguide mechanism and a small reflector, and by replacing the horn with a small reflector and reducing the size, the size and weight of the horn are reduced, and the opening area is kept small. He proposed an array antenna device (Japanese Patent Laid-open No. 31205/1983).

FIG. 11 shows an example of the above-mentioned conventional slot array antenna device. The slot array antenna device shown in the figure has a groove 2a in the web of the holding member 2,
A slot waveguide 1 is inserted and fixed into the groove 2a, and a pair of dielectric plates 3a whose thickness is sufficiently thin compared to the wavelength used is placed at the front end of the slot waveguide 1 with a space of gravity at the front end in between. , 3b
A reflecting plate is provided on the outside of the pair of dielectric plates 3a and 3b to reflect electromagnetic waves transmitted through the vicinity of the bases of the dielectric plates 3a and 3b. 4 is provided in the opening of the holding member 2.

This slot array antenna device uses electromagnetic waves radiated from the slot waveguide l that are radiated at a small angle with respect to the horizontal plane to the inward surfaces (opposite surfaces) of the dielectric plates 3a and 3b. ), and the electromagnetic wave energy emitted forward is increased by reflecting the electromagnetic wave emitted at a large angle forward at the reflector plate 4. forming a directional beam, and
Reduces side lobes.

In this case, the reflector plate 4 only needs to reflect electromagnetic waves emitted from the dielectric base at a large angle, so it can be short and the opening area can be made smaller than in conventional horns. For example, in the case of a conventional horn type, the aperture surface height was more than four times the wavelength used, but in the case of this slot array antenna device, it only needs to be about twice the wavelength, making the aperture area smaller. I can do it.

Although the dual antenna device itself is fully practical, it has the following problems. That is, in the antenna device described above, since the reflector has a trapezoidal opening when viewed from the side, the equiphase plane of the radiated electromagnetic waves becomes cylindrical at the opening, and the width of the main rope increases and the side There is a problem of increasing the lobe.

Furthermore, the antenna device described above has a problem in that since the reflector is short, impedance matching between the inside of the reflector and the free space outside the reflector cannot be achieved at the opening, and unnecessary reflected waves are generated in this portion.

[Purpose of the Invention] The present invention has been made in view of the above-mentioned problems, and its first purpose is to reduce the electromagnetic waves radiated from the opening of the reflector plate by as much as possible the portion where the isophase plane is flat. An object of the present invention is to provide a slot array antenna device in which the width of the main lobe is narrowed and the increase in side lobes is suppressed by radiating the main lobe.

The second purpose is to achieve impedance matching between the free space inside and outside the reflector at the reflector opening, prevent unnecessary waves from occurring in this area, and minimize side lobes. Slot array that can be suppressed
The purpose is to provide an antenna device.

[Configuration of the Invention] In order to achieve the above object, the configuration of the first invention of the present application includes: (a) on the front end side of the slot waveguide, sandwiching a space in front of the front end;
A pair of dielectric plates whose thickness is sufficiently thin compared to the wavelength used is provided protrudingly, and electromagnetic waves transmitted through the vicinity of the base of the dielectric plates and emitted are reflected to the outside of the pair of dielectric plates. A slot array antenna device provided with a reflector, characterized in that (b) the tip edge of the opening of the reflector is extended substantially parallel to the main beam traveling direction of the radiated electromagnetic waves. .

Further, the configuration of the second invention of the present application includes the constituent features (a) and (b) of the first invention, and also includes (c) a reflecting plate made of a synthetic resin material; It is characterized by the addition of a reflective layer made of a conductor inside or on the surface.

Furthermore, the configuration of the third invention of the present application satisfies the above-mentioned configuration requirement (a).
, (b) and (C), and (
d) An L dielectric waveguide mechanism protruding in front of the reflector plate is attached to the opening of the reflector plate with a cover dome.

[Operation of the Invention] Each of the inventions of the present application adds the constituent feature (b) to the slot fist array antenna device that achieves low side lobes based on the above constituent feature (a). The radiated electromagnetic waves are allowed to travel so that their equiphase planes are flat, and the impedances between the inside of the reflector and the free space outside are matched. That is, this reduces the width of the main lobe, suppresses the increase in side lobes, and prevents unnecessary reflected waves from occurring at the opening end of the reflector.

The second invention of the present application maintains the necessary strength by adding constituent feature (C) in addition to the above constituent features.

Efforts are being made to reduce the weight of the reflector. Further, by providing a reflective layer made of a conductive layer inside or on the surface of the synthetic resin plate, it is possible to reflect electromagnetic waves without increasing the weight. Therefore, unlike conventional metal reflectors and horns, the total weight can be reduced, and the load on the rotational drive system can be significantly reduced.

The third invention of the present application further adds a constituent feature (d) to the constituent features of the second invention, whereby the antenna is covered with a radome and a reflector to prevent water and dust from entering inside. I'm here. Furthermore, due to configuration requirement (a), the opening area of the reflector can be made small, so that the antenna can be covered flatly as a whole. As a result, the influence of wind pressure is reduced.

Further, in the third aspect of the invention, by integrally forming the reflector and the radome in a cover shape, it is possible to easily and reliably fix them together, completely prevent water leakage, etc., and furthermore, one reflection The plate and radome can be attached in the same way as a single cover, simplifying assembly work.

Further, the radome is formed of a dielectric plate that is sufficiently thin compared to the wavelength of the electromagnetic waves used so as to be arranged in parallel with the dielectric waveguide mechanism, so that the radome functions as the dielectric waveguide mechanism. Therefore, among the radiated electromagnetic waves, those that would normally be radiated laterally (in a direction perpendicular to the main lobe) and spread out the beam are focused in the traveling direction of the main beam, thereby sharpening the beam.

[Example] Embodiments of the present invention will be described with reference to the drawings.

Structure of First Embodiment> The first embodiment of the slot array analyzer of the present invention shown in FIG.
is fixed to the front end of the slot waveguide 1, with a space in front of the front end in between, and a dielectric waveguide mechanism 3 consisting of a pair of dielectric plates 3a and 3b whose thickness is sufficiently thin compared to the wavelength used. A dielectric plate 3a is provided protrudingly provided on the outside of the pair of dielectric plates 3a and 3b.

A reflector plate 4 for reflecting electromagnetic waves transmitted through the vicinity of the base of the radiator 3b and emitted is provided at the opening of the holding member 2, and furthermore, the tip edge of the opening and opening of the reflector plate 4 is used to reflect the electromagnetic waves transmitted through the vicinity of the base of the radiator 3b. It is provided so as to extend substantially parallel to the beam traveling direction.

This embodiment has basically the same configuration as the antenna device shown in FIG. 11 described above, except for the tip structure of the reflector 4.

The holding member 2 is made of a metal channel material, and has a groove 2a in its web, and the slot waveguide 1 is fitted into the groove 2a. The bases of a pair of dielectric plates 3a and 3b are fixed to the inside of the holding member 2, and these are provided to protrude approximately parallel to each other.

[1. The dielectric waveguide mechanism 3 includes two dielectric plates 3a and 3b made of, for example, FRP (fiber reinforced plastic).
Consists of. The dielectric plate 3a.

3b has a sufficiently thin plate thickness compared to the wavelength input, for example,
Use a plate with a thickness of 0.1 Å or less. In the case of this example, 0.0
It is 78 pieces. The plate thickness needs to be made thinner as the dielectric constant increases, and in this embodiment, a plate with a dielectric constant of about 2.8 is used.

The reason for reducing the plate thickness is to prevent deterioration of the radiation pattern due to electromagnetic waves being tramped within the dielectric plate.

The reflecting plate 4 is made of a metal plate, and has a reflecting part 4b opened at a predetermined angle from the opening of the holding member 2.

This angle θ is experimentally determined in consideration of the incident angle of the electromagnetic waves that pass through the dielectric plates 3a and 3b and enter the reflecting plate 4 so that the radiated electromagnetic waves have a desired beam pattern.

In this embodiment, it is 25 degrees. Further, the length of the reflecting section 4b is set to about twice the input wavelength. In this example, the number of people is 1.56.

The base of the reflection plate 4 serves as a mounting portion for the holding member 2, and is formed integrally with the holding member 2 in this embodiment.

On the other hand, the tip edge of the opening of the reflecting plate 4 is provided with a protrusion 4a extending substantially parallel to the radiation direction of the main beam. That is, in this embodiment, the protruding portion 4a is provided so as to protrude substantially parallel to the dielectric waveguide mechanism 3. However, the protrusion 4a does not necessarily need to be parallel to the radiation direction of the main beam, as long as impedance matching can be achieved and the flat portion of the equiphase front increases. This protrusion 4a has a length d in the radiation direction of the main beam that is 1/4 of the wavelength of the electromagnetic wave used.
level or higher.

Effects of the First Embodiment> In the above-described configuration, a part of the electromagnetic waves emitted from the slot waveguide 1 proceeds forward as it is, and the electromagnetic waves emitted at a larger angle reach the dielectric plate. 3a, 3
It is reflected at b and travels forward. Further, the electromagnetic waves radiated at a large angle pass through the dielectric plates 3a and 3b, are reflected by the reflecting portion 4b of the reflecting plate 4, and proceed forward to the antenna, similar to the other items mentioned above. As a result, an electromagnetic wave beam with few side lobes can be obtained.

At the tip of the reflector 4, the protrusion 4a allows the reflector 3 to
The impedance match with the outside is maintained, and the generation of waves traveling in a direction other than the main beam, that is, the -(2 rise of the side lobe) is prevented. This is because the planar portion of the phase plane increases.

If the protruding part 4a is provided as in this embodiment, the antenna of the same form but without the protruding part will have -20 cl.
The side drop level, which was about B, is reduced to about -22 dB or less.

Configuration of Second Embodiment> The second embodiment of the slot array antenna device of the present invention shown in FIG.
is fixed to the front end of the slot waveguide 1, with a space in front of the front end in between, and a dielectric waveguide mechanism 3 consisting of a pair of dielectric plates 3a and 3b whose thickness is sufficiently thin compared to the wavelength used. A dielectric plate 3a is provided protrudingly provided on the outside of the pair of dielectric plates 3a and 3b.

A reflecting plate 4 that reflects electromagnetic waves transmitted through the vicinity of the base of the holding member 3b and emitted is provided at the opening of the holding member 2,
Furthermore, a protrusion 4a is provided on the tip edge of the opening of the reflector 4 to extend substantially parallel to the main beam traveling direction of the radiated electromagnetic waves.
It is made up of:

In this embodiment, a grid 6- is provided as a vertical polarization suppressing element at the base of the dielectric plates 3a and 3b so as to cover the front end of the slot waveguide l.

Further, in this embodiment, the dielectric plates 3a and 3b are disposed non-parallelly with their tips close to each other. Of course, this can also be applied to the case where they are arranged in parallel. According to such a non-parallel arrangement configuration, side lobes can be suppressed smaller than when the dielectric plates 3a and 3b are arranged in parallel.

The holding member 2 is made of a metal channel material, and as shown in FIGS. 3A and 3B, a groove 2a is provided along the longitudinal direction of the center of the web 2C.

This groove portion 2a is provided with a through hole 2b.

A plurality of through holes 2b are provided along the longitudinal direction on the bottom surface of the groove portion 2a. In this embodiment, the through hole 2b is formed as a long hole, but it can be formed in any suitable shape such as a circular hole or a square hole. The through hole 2b is provided at a position where the slot waveguide 1 is to be installed, and is arranged so that when the waveguide 1 is fixed, it protrudes from the rear surface and prevents electromagnetic waves from leaking.

A through hole 2d is provided in the parallel piece portion of the holding member 2, and a dielectric plate 3, which will be described later, is
a, 3b, the reflecting plate 4, and the grid 6 are fixed to the holding member 2 with bolts, nuts, etc. 12a, 12b.

The slot waveguide 1 has a plurality of slots 1a cut into its front end surface. The waveguide l has a groove portion 2 on its rear surface side.
a, and the rear surface is welded to the inner wall of the L reporter through hole 2b to be fixed to the holding member 2. However, the fixing of the waveguide 1 and the holding member 2 is not limited to welding, and any known fixing means such as adhesion or screwing can be used.

-1- The dielectric waveguide mechanism 3 is made of, for example, FRP (fiber reinforced plastic), and has two dielectric plates 3'a and 3'bi which are sufficiently thinner than the wavelength input. consists of one. As described in the first embodiment, the plate thickness is, for example, 0.1 Å or less, and in the case of this embodiment, 0.0
There are 78 people.

The dielectric plates 3a and 3b are each formed into a plate shape with a slightly new curve in the vicinity of the base, and the extension lines of the outward surfaces approach each other at the tip side, so that the base is connected to the parallel piece of the holding member 2. It is fixed on the outside.

The dielectric plate is bent at an extremely small angle of about 1 to 5 degrees, although it varies depending on the length of the chain plate, the length of the reflector, and the opening angle. However, a parallel plane dielectric plate,
It may be bent when attached to the holding member 2.

The reflecting plate 4 is made of a synthetic resin material such as FRP (fiber-reinforced plastic), and is molded into a flat plate bent at a predetermined angle in a direction orthogonal to the longitudinal direction. This angle θ is experimentally determined in consideration of the incident angle of the electromagnetic waves passing through the dielectric plates 3a and 3b so that the radiated electromagnetic waves have a desired beam pattern. In this embodiment, it is 25 degrees.

The base side of the reflecting plate 4 serves as a mounting portion 4C for the holding member 2, and the tip side serves as an electromagnetic wave reflecting portion 4b. Further, the opening of the reflection plate 4 is provided with a protrusion 4a.

As described above, the protruding portion 4a is provided by extending and protruding the tip edge of the opening of the reflecting plate 4 substantially parallel to the radiation direction of the main beam. However, the protrusion 4a does not necessarily need to be parallel to the radiation direction of the main beam, as long as the impedance matching can be achieved and the flat plate-like portion of the equiphase front increases. As in the first embodiment, the length d of the protrusion 4a in the radiation direction of the electromagnetic wave is set to 1/4 of the wavelength of the electromagnetic wave used.
To some extent.

On the other hand, the mounting portion 4C is screwed together with the dielectrics 3a, 3b and the grid 6 on the outside of the parallel piece of the holding member 2 indicated by F using a port 12a and a nut 12b.

The protruding portion 4a and the reflecting portion 4b are, as shown in FIG. 4A,
A thin metal plate 5 is buried in the middle part in the thickness direction,
It constitutes a reflective layer. The length of this reflecting section 4b is set to about twice the wavelength λ used. In this example, 1.
It comes in 56 pieces.

This metal plate 5 has multiple through holes 5a, as shown in FIGS. 4A and 4B. This through hole 5a not only lightly oxidizes the metal plate 5, but also allows the synthetic resin material under L of the metal plate 5 buried in the intermediate portion to pass through when forming the reflective plate 4.
act to connect with each other. Therefore, the reflecting portion 4b is strongly formed using the metal plate 5 as a reinforcing material.

The size of the through hole 5a is limited in the direction orthogonal to the electric field vector of the polarized wave used in order to prevent the electromagnetic wave to be reflected from passing backward. That is, the wavelength is set to 1/2 or less of the wavelength of the electromagnetic waves used.

In the case of this embodiment, in order to obtain a sufficient reflection effect, the through hole 5a
is formed in the shape of a circular hole with a diameter of 3 mm. However, the through hole 5a is not limited to a circular hole, but may be a square hole or a slit shape.

The grid 6 consists of a metal plate bent in a U-shape, and the fifth
As shown in the figure, a large number of slits 6a are provided at predetermined intervals in a web 6b of a U-shaped metal plate, perpendicular to the longitudinal direction. This grid 6 has a U-shaped opening portion fitted onto the outside of the parallel piece of the holding member 2, and as described above, the dielectric plates 3a, 3
b and the reflector 4 through the through hole 6C.
a. It is fixed with a nut 12b.

This slit 6a is provided along the entire height of the web 6b, and the height h is set to be at least 1/2 of the wavelength used so as not to suppress the horizontally polarized component to be radiated.

Further, the width S of the slit 6a is set to be smaller than 1/2 of the wavelength in order to suppress vertically polarized components. Further, the spacing between each slit 6a is set to be as small as the slit width in order to prevent reflection at this portion. In the case of this embodiment, the height h is 25 m, the width S is 2 mm, and the interval is 21Il+m.

This grid 6 is held between the base ends of the dielectric plates 3a and 3b, and covers the front end of the slot waveguide 1 with a web 6b having a group of slits. The distance between the position of the slint rod a and the front end of the waveguide l is maintained at approximately 3/4 of the wavelength so as not to suppress the radiation of electromagnetic waves. In the case of this example, 2
It is 4mm.

Note that the grid 6 is not limited to being made of metal; it may also be a U-shaped plate made of a non-metallic material such as plastic, provided with slits 6a, and coated with a conductive layer on the surface thereof.

Functions and Effects of Second Embodiment> Next, the functions of the second embodiment will be described with reference to the drawings.

In the above-described configuration, when an electromagnetic wave is emitted from the slot waveguide 1, the electromagnetic wave reaches the inside of the web 6b either directly within the grid 6 or reflected from the inner surface of the grid 6, and causes a current distribution in the grid 6. Note that among the radiated electromagnetic waves, those that proceed toward the rear side are reflected by the webs 2C of the holding member 2, proceed forward, and reach the grid 6.

This current distribution is cut by the slit 6a and emits electromagnetic waves. At this time, since the height h of each slit 6a is longer than 1/2 wavelength, and the width S is extremely shorter than 1/2 wavelength, only horizontally polarized waves having an electric field component in the longitudinal direction of grid 6 are generated. can exist, and vertical polarization is suppressed.

Among the electromagnetic waves radiated from the grid 6, those having a small emission angle directly pass between the dielectric plates 3a and 3b and proceed toward the front of the antenna. The dielectric plate 3a has a larger emission angle than this.

It is reflected at 3b and similarly travels forward. Those with a larger emission angle pass through the dielectric plates 3a and 3b, enter the reflection plate 4, are reflected by the reflection layer made of the metal plate 5, and proceed in the forward direction of the antenna. At this time, metal plate 5
Since the transparent hole 5a provided in FIG.

Here, the function of the protrusion 4a of the reflection plate 4 is as follows.

Since it is the same as the case of the L distribution 1 embodiment, the explanation will not be repeated.

Next, the mechanical effects of the second embodiment will be described.

In the second embodiment, the slot waveguide 1 is fixedly supported by a metal holding member 2, and together with the reflection plate 4 and the dielectric waveguide mechanism 3, constitutes an antenna device. In this case, the waveguide l has its rear surface held by holding members 2 at multiple locations in the longitudinal direction.
Since it is fixed to the holding member 2, it is regulated by the holding member 2 and will not bend during or after installation. the result,
No phase disturbance occurs in the radiated electromagnetic waves. Moreover, the reflector 4
, dielectric plates 3a, 3b and grid 6 with bolts.

Since it is configured to be fixed to the holding member 2 all at once by the nuts 12a and 12b, assembly is extremely easy.

Furthermore, in the device of this embodiment, a plurality of through holes 2b are provided in the holding member 2, which is the heaviest among the components of the antenna device, so that its weight is reduced;
Since it is not a two-point support structure at both ends, but a distributed fixed support structure by fixing in the plurality of through holes,
Reduces weight and rotational moment. Therefore, when this antenna device is used for radar, it is possible to reduce the burden on the rotational drive system that drives the antenna.

Furthermore, according to the above configuration, most of the reflective plate 4 is made of light synthetic resin, and the remaining metal portion is also extremely thin, so that the total weight of the reflective plate 4 is reduced. As a result, the thickness of the holding member 2 that supports the reflecting plate 4 can be made thinner, and the overall weight of the antenna can be reduced. As a result, the weight burden on the installation location such as the mast can be reduced.

Third Embodiment A third embodiment of the slot array antenna device of the present invention shown in FIGS. 6 and 7 has a radome 7 attached to the opening of the reflector of the antenna device of the second embodiment. It consists of There is also an example of Kimi Peng.

The reflecting plate 4 is provided with overlays 4d and 4e, and the protruding portion 4a of the reflecting plate 4 is provided with an attachment fixing member 8. Note that description of the same parts as in the second embodiment will be omitted.

The reflector plate 4 has an overlay 4d attached at a proper position in the longitudinal direction from the outer reflective part 4b to the attachment part 4c. This overlay 4d is made of FRP similarly to the reflection plate 4. In this embodiment, as shown in FIG. 7, two tubes are provided at the longitudinally intermediate portion, but they may be provided at three or more locations.

Moreover, on the protruding part 4a and the reflecting part 4b near the protruding part 4a,
An overlay 4e is provided along the longitudinal direction. These overlays 4d and 4e are attached to the reflective plate 4 with adhesive.
is attached to.

A radome 7, which will be described later, is fixed to the protrusion 4a.

As shown in FIGS. 8A and 8B, the end of the radome 7 is attached to the outside of the protrusion 4a, and the top of the radome is covered with the overlays 4e and 4d to be firmly fixed. . As a result, the reflector plate 4 and the radome 7 are integrally fixedly connected at each other's openings, and the entire structure functions as a cover. This integration is performed in advance before assembly with other components.

The radome 7 is made of, for example, pRP (FI1m reinforced plastic), and is formed to sandwich the dielectric waveguide mechanism 3 with an appropriate space between them. And dielectric plate 3
Portions 7a and 7b arranged in parallel with a and 3b constitute a second dielectric waveguide mechanism. In this embodiment, the dielectric plate 3a
, 3b, but may be formed from a different material.

Like the dielectric plates 3a and 3b, this radome 7 has a thickness that is sufficiently thin compared to the input wavelength, for example, 0.1
In the case of this embodiment using a plate of Å or less, this plate thickness is
The value is 0.05λ. Note that the plate thickness is the dielectric plate 3 mentioned above.
For the same reason as in cases a and 3b, it is necessary to make the material thinner as the dielectric constant increases.

The radome 7 has dielectric plates 3a, 3b juxtaposed portions 7a, 7.
b is formed into a parabolic shape with two apexes in the direction of the tip so that they approach the tip. The reason why the dome 7 is narrowed toward the tip is to avoid increasing side lobes such as back lobes that occur at angles far away from the main beam. However, the dielectric plates 3a, 3b juxtaposed portion 7a
, 7b in parallel, the beam focusing effect is not lost.

Although this radome 7 can be omitted, it is desirable to include it because it functions not only as a cover for the antenna opening but also as a second dielectric waveguide mechanism that narrows the beam of radiated electromagnetic waves.

On the reflection plate protrusion 4a located away from the front end of the slot waveguide 1, at the position where the overlay 4d is attached, there is a plate which is sufficiently thin compared to the wavelength of the electromagnetic wave used, for example, in this embodiment. Now, the fixing member 8 with a diameter of about 4 mm, which is 1/8 or less of the wavelength, is inserted through the through holes 3C provided in the dielectric plates 3a and 3b and the through hole 13a of the support member 13, and is inserted between the walls facing the reflector. I handed it over and put it on.

This fixing member 8 is threaded at both ends and is fixed with nuts 9 above and below the protrusion 4a. In this embodiment, two fixing members 8 are attached, but depending on the length of the antenna, three or more fixing members 8 may be attached. In this case, the fixing members 8 are arranged at intervals that do not suppress the polarized wave component used.

Further, this fixing member 8 has one end (lower end in this embodiment) protruding outward from the reflection plate protrusion 4a to serve as a mounting part 8a for the mounting location, and the rotation drive system 10 is connected to the rotation drive system 10 by the nut 9. It is fixed to the antenna support part 11.

Effects of the third embodiment> The effects of the third embodiment are the same as those of the second embodiment, except for the effects of the radome 7 and the fixing member 8, so only these will be explained. , other components will not be repeated.

A part of the electromagnetic waves emitted from the dielectric plates 3a, 3b or the reflector 4 is reflected by the radome 7, which covers the dielectric plates 3a, 3b and the reflector 4, and travels in the forward direction of the antenna. Therefore, a part of the electromagnetic waves that would normally travel in the vertical direction of the antenna and spread the beam are concentrated and concentrated so that they travel forward, resulting in a sharpened radiation beam.

-4-12 An actually measured radiation pattern of electromagnetic waves radiated from the antenna device of the third embodiment is shown in FIG. 9A. This is L
When compared with the actually measured radiation pattern (Fig. 9B) of the antenna device of the distribution example 1 excluding the radome 7, the sidelobe level is slightly higher in the antenna device of the song title, that is, the above example, but the beam half width is , i.e. -3dB
It can be seen that the beam width is 22 degrees, which is sharper than the latter 24 degrees, and the antenna gain is increased.

Next, the mechanical effects of the above embodiment will be described.

According to the above embodiment, the radome 7 completely covers the front part of the open part of the reflecting plate 4, so that water and dust can be prevented from entering. Further, since the tip of the radome 7 is narrowed and the opening area of the reflector 4 is small, the overall cover is flat, reducing the influence of wind pressure. Furthermore, since the radome 7 and the reflector 4 are integrated, water leakage does not occur at the joint between the two, and the reflector 4 and the radome 7 are attached at the same time during assembly. The production process can be simplified.

Further, according to this embodiment with the above configuration, the upper and lower reflectors are
Since both are supported by the fixing member 8, the reflecting plate 4 does not need to be particularly thick. Moreover, since the lower end of the fixing member 8 is used as the attachment part 8a for the antenna support part 11, and the weight of the reflector plate 4 is directly received by the antenna support part 11, the attachment can be carried out without mechanical stress, and a special Since no parts are required, the number of parts does not increase. In addition, the reflective plate protrusion 4a can be reliably positioned,
Furthermore, since the reflecting plate is made of synthetic resin and can be slightly deformed when fixed with the nut 9, the aperture angle can be finely adjusted, which is convenient.

Configuration of Fourth Embodiment> The fourth embodiment of the throat array antenna device of the present invention shown in FIG. It is configured by loading the support member 13. Therefore, except for the support member 13, the other parts have the same structure as the third embodiment, so the description of the same parts will not be repeated.

The support member 13 is made of a radio-transparent material, that is, a dielectric material with a relative dielectric constant close to 1. As this support member 13, a foamable material such as expanded polystyrene is suitable, for example. Of course, it does not have to be a foam material, but a foam material has a small specific gravity and is lightweight, so it has the advantage of not increasing the weight of the antenna. In addition, the dielectric constant of the foam material can be set arbitrarily by appropriately selecting the specific gravity, foaming rate, etc.
It has the advantage that it can be formed with desired characteristics.

In order to use a foamed material as the support member 13, for example, a foamed material that has been preformed with a mold is inserted between the dielectric plates 3a and 3b and bonded with an adhesive. Alternatively, the dielectric plates 3a and 3b may be fixed in a suitable mold, and a foam material may be foamed and filled between the dielectric plates 3a and 3b.

Note that when loading the support member 13, the dielectric plates 3a, 3
If a plurality of spacers 14 made of a material having the same properties as the support member 13 are fitted along the longitudinal direction at the tip of the support member 13, the dielectric plates 3a, 3b and the radome 7 can be positioned. It's convenient and easy to do.

Further, it is desirable that a dense skin layer be formed on the surface of the support member 13 on which electromagnetic waves are incident, that is, the surface facing the grid 6, which will be described later. Thereby, it is possible to prevent scattering of incident electromagnetic waves and prevent collapse of the end portion of the support member 13.

In addition, in this embodiment, the support member 13 is loaded between the dielectric plates 3a and 3b, but only the dielectric plate 3a.

It can also be loaded between the dielectric plates 3b and the radome, and in this way, the dielectric plates 3a and 3b can be supported more firmly.

Functions and Effects of the Fourth and Fifth Embodiments The fourth embodiment basically operates in the same manner as the third embodiment, so only the functions related to the support member 13 will be explained, and the effects related to other configurations will be explained. The explanation will not be repeated.

is radiated from the slot waveguide 1 and reaches the grid 6,
The electromagnetic waves re-radiated from the grid 6 are transmitted to the support member 13
incident on . Since the support member 13 has a dielectric constant close to 1, it acts as a transparent body for electromagnetic waves and does not hinder the movement of the electromagnetic waves. Further, when the end face of the support member 13 is a skin layer, scattering of incident electromagnetic waves is prevented.

Further, since the dielectric plates 3a and 3b are held by the support member 13, the dielectric plates 3a and 3b do not bend and do not swing due to shaking caused by wind or waves. Therefore, fluctuations in side lobes are prevented.

Modifications of the above embodiments> Firstly, in the second to fourth embodiments above, the reflective layer is made of a metal plate with many through holes, but it is not limited to this. It can also be configured by being embedded in a synthetic resin material.

Alternatively, a conductive layer may be formed on the surface of the reflective plate to serve as a reflective layer. In these cases and each of the above examples, the reflective layer may not be porous or reticulated, but may be a uniform layer.

Second, in each of the above embodiments, a planar reflecting plate is used, but the present invention is not limited to this, and a curved reflecting plate such as a paraboloid may also be used.

Thirdly, in the second to fourth embodiments of Section 1, a grid is used as the vertical polarization suppressing element, but the grid is not limited to this.
Metal blocks etc. can be used.

Fourthly, in the third and fourth embodiments, the tip of the radome is curved, but it may be flat.

[Effects of the Invention] As explained above, the present invention provides an antenna device equipped with a dielectric waveguide mechanism consisting of a pair of dielectric plates, in which the equiphase plane of electromagnetic waves radiated from the opening of the reflector plate is formed into a planar shape. By doing so, the main lobe can be made narrower, the side lobes can be kept as small as possible, and impedance matching can be achieved between the free space inside and outside the reflector at the reflector opening, thereby eliminating the need for this part. This has the effect of preventing the generation of reflected waves.

[Brief explanation of the drawing]

FIG. 1 shows the first slot-array antenna device of the present invention.
A perspective view showing a main part of the embodiment, Figures 2 and 1 are perspective views showing a second embodiment of the present invention thrower)-array antenna device,
FIG. 3A is a partial perspective view showing how the slot waveguide is held by the holding member in the second embodiment, FIG. 3B is a cross-sectional view thereof, and FIG. 4 is the structure of the reflector used in the second embodiment. FIG. 5 is a perspective view showing an example of the grid used in the second embodiment, and FIG. 6 shows a third embodiment of the thrower-array-antenna device of the present invention. A partially cutaway side view, FIG. 7 is a perspective view showing the structure of the antenna constituting the main part of the third embodiment, and FIG. 8A shows a state in which the reflector and radome in the third embodiment are integrated. A cross-sectional view, FIG. 8B is a partial cross-sectional view showing the fixed state of the reflector and the radome in the third embodiment, FIG.
Figure A is a characteristic diagram showing the measured radiation pattern of the third embodiment, Figure 9B is a characteristic diagram showing the measured radiation pattern of the third embodiment with the radome removed, and Figure 10 is the fourth embodiment of the present invention. FIG. 11 is a perspective view showing the main part of a conventional slot array antenna device equipped with a dielectric waveguide mechanism. DESCRIPTION OF SYMBOLS 1... Slot waveguide 2... Holding member 3... Dielectric waveguide mechanism 4... Reflection plates 3a, 3b... Dielectric plate 4a... Opening part 4b... Reflection part 4c...Mounting part 4d, 4e...Overlay 5...Metal plate 5a...Through hole 6...Grid 6a...Slit 7...Radome 8...Fixing member 7a, 7b. ...Dielectric plate juxtaposed portion 8a...Mounting part 9...Nut 10...Rotation drive system 11...Antenna support part 12
a...Port 12b...Nut 13...Supporting member 14...Spacer applicant Tokyo Keiki Co., Ltd. Agent Patent attorney Iwao Mishina Figure 2 Figure 3A Figure 3B Figure 4! Fig. 5 Fig. 6 Fig. 9A Fig. 9B (dB) Procedural amendment stamp) 1] Patent Office Commissioner Gakudon Shiga 1, Indication of the case Patent Application No. 117785/1982 2, Name of the invention Slowa I... Array antenna device 3, relationship with the person making the correction Patent applicant address 2-16-46 Minami Kamata, Ota-ku, Tokyo Name (338) Tokyo Keiki 4, Agent 220 5. Claims column of the specification subject to amendment Column 6. Detailed explanation of the invention of the specification The phrase "in front of the front end of the waveguide 1" is corrected to "in front of the waveguide 1." (b) In the second line of page 8 of the specification, the phrase [at the front end of the waveguide, in front of the front end] has been replaced with "at the front of the waveguide, in front of the front end".
I am corrected. Cc) On page 11, lines 11 and 12 of the specification, the phrase "at the front end of the waveguide 1, in front of the front end" is corrected to "in front of the waveguide 1, in front of the front end." (d) On page 15 of the specification, lines 5 and 6, “Waveguide 1
The phrase "in front of the front end of the waveguide 1" is corrected to "in front of the waveguide 1." (e) The sentences from page 21, line 18 of the specification, "In the above configuration," to page 22, lines 5-6, "radiate electromagnetic waves," are corrected as follows. "In the above-described configuration, when an electromagnetic wave is emitted from the slot waveguide 1, the electromagnetic wave reaches the inside of the wed 6b, and the electromagnetic wave with a predetermined polarization passes through the slit 6a and is emitted." (f) Specification On page 22 of the book, lines 9 and 10, it says, "Only horizontally polarized waves can exist, and vertically polarized waves are suppressed." instead of "Only horizontally polarized waves can pass through the slit,
Vertical polarization parallel to a is suppressed. ” he corrected. Amended Claims (1) A pair of dielectric plates protruding from the front side of the slot waveguide, sandwiching the space in front, the plate thickness being sufficiently thin compared to the wavelength used, and In the slot array antenna device, a reflector is provided on the outside of the pair of dielectric plates to reflect electromagnetic waves transmitted through the vicinity of the base of the dielectric plate and emitted. , a slot array antenna device extending substantially parallel to a main beam traveling direction of radiated electromagnetic waves. (2) A pair of dielectric plates, whose thickness is sufficiently thin compared to the wavelength used, are provided protrudingly on the front side of the slot waveguide with a space in front of the slot in between, and the pair of dielectric plates are In a slotted array antenna device that is provided with a reflector on the outside that reflects electromagnetic waves transmitted through the vicinity of the base of a dielectric plate and then emitted, the leading edge of the opening of the reflector is used as the main beam of the emitted electromagnetic wave. Provided to extend approximately parallel to the direction. A slot array antenna device characterized in that the reflecting plate is made of a synthetic resin material, and a reflecting layer made of a conductor is provided inside or on the surface of the reflecting plate. (3) On the front side of the slot waveguide, a pair of dielectric plates whose plate thickness is sufficiently thin compared to the wavelength used are provided protrudingly across a space in front of the slot waveguide, and On the outside of the dielectric plate,
In a slot array antenna device comprising a reflector that reflects electromagnetic waves transmitted through the vicinity of the base of a dielectric plate and emitted, provided extending substantially parallel to the
The reflective plate is formed of a synthetic resin material, and a reflective layer made of a conductor is provided inside or on the surface of the reflective plate. A slot array antenna device comprising a radome covering a body waveguide mechanism. (4) The slot array antenna according to claim 3, characterized in that the reflector and the radome are fixedly connected at each other's openings to form an integral cover shape. Device. (5) In claim 3 or 4 above,
A slot array characterized in that the radome is formed of a dielectric plate having a thickness sufficiently thin compared to the wavelength of the electromagnetic waves used, so as to have a portion arranged in parallel with the dielectric waveguide mechanism. antenna device.

Claims (5)

[Claims] (1) A pair of dielectric plates whose thickness is sufficiently thin compared to the wavelength used are provided protrudingly on the front end side of the slot waveguide with a space in front of the front end in between, and the pair of dielectric plates outside of
In a slot array antenna device comprising a reflector that reflects electromagnetic waves transmitted through the vicinity of the base of a dielectric plate and emitted, the leading edge of the opening of the reflector is generally referred to as the main beam traveling direction of the emitted electromagnetic waves. A slot array antenna device characterized by being provided with parallel extensions. (2) A pair of dielectric plates, whose thickness is sufficiently thin compared to the wavelength used, are provided protruding from the front end side of the slot waveguide with a space in front of the front end in between, and the pair of dielectric plates outside of
In a thrower (thrower) array antenna device comprising a reflector that reflects electromagnetic waves transmitted through the vicinity of the base of a dielectric plate and emitted, the leading edge of the opening of the reflector is aligned with the main beam traveling direction of the emitted electromagnetic waves. The reflective plate is provided to extend substantially in parallel, and is formed of a synthetic resin material, and inside or on the surface thereof,
A slot array antenna device comprising a reflective layer made of a conductor. (3) A pair of dielectric plates whose thickness is sufficiently thin compared to the wavelength used are provided protrudingly on the front end side of the slot waveguide with a space in front of the front end in between, and the pair of dielectric plates outside of
In a slot array antenna device that is provided with a reflector that reflects electromagnetic waves transmitted through the vicinity of the base of a dielectric plate and then emitted, the main beam of the emitted electromagnetic waves travels along the tip edge of the opening of the reflector. The reflecting plate is provided to extend substantially parallel to the direction, and is made of a synthetic resin material, and is made of a conductor inside or on the surface thereof. A slot array antenna device comprising: a reflective layer; and a radome that covers the dielectric waveguide mechanism protruding in front of the reflective plate is attached to the opening of the reflective plate. (4) In claim 3, the slot device is characterized in that the reflector and the radome are fixedly connected at each other's openings to form an integral cover shape.
Arrays and antenna equipment. (5) In claim 3 or 4 above,
A slot fist array characterized in that the radome is formed by a dielectric plate whose thickness is sufficiently thin compared to the wavelength of the electromagnetic waves used so as to have a portion that is arranged in parallel with the dielectric waveguide mechanism described above. φ antenna device.