JPH0897628A - Planar antenna - Google Patents

Abstract

PURPOSE: To provide a plane antenna in which a degree of design is increased and especially a position or a direction of a converter is changed. CONSTITUTION: The planar antenna 20 is provided with a radial guide path 28 comprising a slot plate 21, a conductor plate 23 and a dielectric layer 22 interposed between them, a center conductor 24 inserted in the inside of the radial guide path 28, a waveguide 26 connecting to the center conductor 24, and a converter 27 connecting to the waveguide 26. Then the center conductor 24 and the waveguide 26 are connected via a printed circuit board 25 arranged perpendicularly to them, and a land 37b used to connect the center conductor 24 and a microstrip line 42 tying a center point of a waveguide connection section and the land are formed on the printed circuit board 25.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a planar antenna utilizing a waveguide space such as a radial waveguide used in SHF and EHF bands.

[0002]

2. Description of the Related Art Conventionally, bowl-shaped parabolic antennas have been generally used in the field of satellite communication and the like, but in recent years, planar antennas having high performance equivalent to high-performance parabolic antennas have been provided. There is.

An example of this type of flat antenna is shown in FIG. 6 disclosed in Japanese Patent Application No. Hei 2-401704. This planar antenna 1 is a so-called radial line slot antenna,
Reference numeral 2 in the figure denotes a conductor frame (conductor plate) that constitutes the rear surface side of the planar antenna 1. In this case, the conductor frame 2 has a circular shape as viewed from the front and has a flat container shape with an open upper portion.

Inside the conductor frame 2, a circular slot plate 3 having a large number of slots (not shown) is separated from the conductor frame 2 by interposing a dielectric layer 5 between the conductor frame 2 and the conductor frame 2. It is provided to face each other. A void 5a is formed near the axis of the dielectric layer 5. A circular flat radial waveguide 6 (waveguide space) is formed by the slot plate 3, the conductor frame 2, and the dielectric layer 5 interposed therebetween.

A radome 7 which constitutes the front surface of the planar antenna 1 is mounted on the opening side of the conductor frame 2, and a spacer 8 is provided between the radome 7 and the slot plate 3. The radome 7 is a cover provided on the front surface of the planar antenna 1 and fitted to the conductor frame 2 in order to avoid adverse effects such as rain and snow when the planar antenna 1 is installed outdoors.

Further, an opening 9 is formed in the lower central portion of the conductor frame 2. A cylindrical coaxial line 10 is provided around the opening 9 with its axis aligned with the slot plate 3, whereby the radial waveguide 6 is provided.
And the coaxial line 10 communicate with each other. Also,
A waveguide 11 is provided below the coaxial line 10 in communication with the coaxial line 10, and a converter 12 is provided on one side of the waveguide 11.
Is provided.

Here, inside the coaxial line 10, a central conductor 14 fitted in a hollow cylindrical dielectric 13 has its axis aligned with the slot plate 3, and its upper end is located inside the radial waveguide 6. And is fixed with the lower end positioned inside the waveguide 11. That is, the central conductor 14 is
The coaxial line 10 is formed by the dielectric 13 formed in a hollow cylindrical shape.
It is fitted and fixed inside, and the top loading portions 15 and 16 are formed by expanding both ends thereof. These top loading parts 15 and 16 are for improving the power feeding efficiency by expanding the outer diameters of the upper and lower ends of the center conductor 14.

The central conductor 14 fitted in the dielectric 13 is inserted into the coaxial line 10 in a state where the bottom surface of the dielectric 13 is in contact with the inner surface of the waveguide 11. As a result, the center conductor 14 is fixed inside the coaxial line 10, the top loading portion 15 at the upper end is located inside the radial waveguide 6 and is separated from the slot plate 3 by a predetermined distance, and at the lower end. The top loading portion 16 of the portion is inserted into the dielectric 13 and the waveguide 1
It will be in the state arrange | positioned in the predetermined position in 1.

[0009]

By the way, in the planar antenna 1 having the above-described structure, the positional relationship between the respective members such as the position of the central conductor 14 with respect to the slot plate 3 and the dimensions of the respective members are extremely large in view of the characteristics of the planar antenna. This is important, and if a certain member deviates from the set position by an allowable dimension or more, various problems will occur in terms of performance, such as a significant decrease in the matching of the planar antenna. Therefore, the position and size of each member in the planar antenna are necessarily determined based on the design parameters required from the performance side of the antenna.

Therefore, the size and shape of the planar antenna, the positional relationship with other members such as mounting brackets, etc.
In some cases, the converter 12, which is a component having a relatively large size in the planar antenna 1 having the above configuration, may interfere with other members. However, as described above, since the positions and dimensions of each member are determined based on the design parameters from the performance side, the degree of freedom in designing these positions and dimensions is extremely small, so the converter 12 does not interfere with other members. There was a problem that it could not be easily moved to an appropriate place.

The present invention has been made in order to solve the above-mentioned problems, and it is possible to increase the degree of freedom in design, and particularly to move the position of a converter which is a relatively large-sized component. The purpose is to provide a planar antenna.

[0012]

In order to achieve the above-mentioned object, a plane antenna according to a first aspect of the present invention comprises a slot plate and a conductor plate facing each other apart from each other and a dielectric layer interposed therebetween. A formed radial waveguide, a coaxial line inserted into the radial waveguide from the side of the conductor plate in the radial waveguide, and a tip end of which is disposed in proximity to the slot plate and connected to the coaxial line In a planar antenna comprising a waveguide and a converter connected to the waveguide, the coaxial line and the waveguide,
The coaxial lines are connected to each other via a printed wiring board arranged perpendicularly to the extending direction of the waveguide, and the printed wiring board has a land portion to which the coaxial line is connected and the inside of the waveguide. It is characterized in that a microstrip line connecting to the position corresponding to is formed.

Further, the plane antenna according to claim 2 is
A radial waveguide formed by a dielectric layer interposed between a slot plate and a conductor plate which are spaced apart from each other and faced to each other, and the radial waveguide is inserted into the radial waveguide from the conductor plate side, A planar antenna comprising a coaxial line whose tip is disposed in the vicinity of the slot plate, a waveguide connected to the coaxial line, and a converter connected to the waveguide, The wave guide is composed of a first waveguide connected to the coaxial line and a second waveguide connected to the converter, and the first and second waveguides are connected by these guides. Micro boards that are respectively connected through printed wiring boards that are arranged perpendicularly to the extending direction of the waveguide and that connect positions corresponding to the insides of the first and second waveguides to the printed wiring board. Stripline is formed It is characterized in.

The plane antenna according to claim 3 is
In the printed wiring board, a shield through hole is formed at a position along the tube wall of the waveguide, the shield through hole penetrating the front and back of the printed wiring board and having an inner wall surface covered with a plating layer. Is.

[0015]

In the plane antenna according to the first aspect of the present invention, the coaxial line and the waveguide are connected to each other through the printed wiring board. Therefore, by changing the dimensions of the printed wiring board appropriately, the radial guide is provided. The positions of the waveguide and the converter with respect to the waveguide and the coaxial line can be freely set. Further, since the printed wiring board is arranged perpendicularly to the extending direction of the coaxial line and the waveguide, the converter can be turned by 90 ° with respect to the conventional planar antenna. When this planar antenna is used as a receiving antenna, for example, electromagnetic waves are transmitted from the radial waveguide to the coaxial line, and then to the waveguide and the converter through the microstrip line on the printed wiring board.

Further, in the planar antenna according to the second aspect of the invention, the first waveguide connected to the coaxial line and the second waveguide connected to the converter are connected via the printed wiring board. Therefore, the positions of the radial waveguide, the coaxial line, and the second waveguide and the converter with respect to the first waveguide can be freely set by appropriately changing the dimensions of the printed wiring board. . When this planar antenna is used as a receiving antenna, for example, electromagnetic waves are transmitted from the radial waveguide to the coaxial line to the first waveguide.
The second waveguide and the converter are transmitted through the second waveguide and the microstrip line on the printed wiring board.

Further, in the flat antenna according to the third aspect of the present invention, since the through hole for shielding which penetrates the front and back of the printed wiring board and is covered with the plating layer is formed at a position along the tube wall of the waveguide. , When the electromagnetic wave is transmitted through the inside of the printed wiring board in the thickness direction, the through hole for shielding functions as if it were a part of the waveguide, and the electromagnetic wave is transmitted with a small transmission loss. .

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 shows a planar antenna 20 of this embodiment.
FIG. 3 is a diagram showing a plane antenna 20 used as a satellite broadcast receiving antenna, for example. In the figure, reference numeral 21 is a slot plate, 22 is a dielectric layer, 23 is a conductor plate, 24 is a central conductor (coaxial line), 25 is a printed wiring board, 26 is a waveguide, and 27 is a converter.

A large number of slots (not shown) for generating excitation are spirally formed on the surface of the disk-shaped slot plate 21, and the planar antenna 20 constitutes a so-called radial line slot antenna. are doing. The slot plate 21 is provided so as to be separated from the conductor plate 23 by a predetermined dimension by interposing the dielectric layer 22 made of foam, for example, and to face the conductor plate 23.
A void 22a is formed near the axis of the dielectric layer 22. A disk-shaped radial waveguide 28 is formed by the slot plate 21, the conductor plate 23, and the dielectric layer 22 interposed therebetween.

Further, the opening 2 is formed at the center of the conductor plate 23.
9 is formed. A cylindrical coaxial line 30 is provided around the opening 29 with its axis aligned with that of the disk-shaped radial waveguide 28, so that the radial waveguide 28 and the coaxial line 30 communicate with each other. It is structured. Here, inside the coaxial line 30, the central conductor 24 fitted in the hollow cylindrical dielectric 31 is aligned with the radial waveguide 28 in the axis line, and the upper end is located inside the radial waveguide 28. It is fixed at. Further, the upper end portion of the center conductor 24 is expanded in diameter to form a top loading portion 32. The top loading portion 32 is for improving the power feeding efficiency by expanding the outer diameter of the upper end portion of the central conductor 24 facing the slot plate 21.

The central conductor 24 and the waveguide 26 are connected via a printed wiring board 25. That is, the printed wiring board 25 is covered with the shield case 35 including the upper case 33 and the lower case 34, and one end side thereof is connected to the lower end portion of the center conductor 24, and the other end side thereof is connected to the waveguide 26 and the converter 27. It is connected. In addition,
In this embodiment, the waveguide 26 is composed of an upper case 33 and a lower case 34 located above the converter 27.

The printed wiring board 25 is a double-sided printed wiring board made of a glass epoxy resin substrate or the like having copper foil adhered on both sides, and the front side in FIG. 1 has the configuration shown in FIG. 2 and the back side has the configuration shown in FIG. ing. That is, as shown in FIG. 2, on the front surface side of the printed wiring board 25, a center conductor connecting through hole 36 having a diameter into which the center conductor 24 can be inserted is formed on one end side, and the center conductor connecting through hole 36 is formed. A land portion 37a is formed around the hole 36. A waveguide connecting portion 38a, in which the conductor is removed in a rectangular shape, is formed on the other end side so as to substantially coincide with the inner wall of the waveguide 26, and the waveguide connecting portion 38a is surrounded and guided. Wave tube 2
A large number of shield through holes 39, 39, which penetrate the front and back surfaces of the printed wiring board 25 and whose inner wall surfaces are covered with a plating layer, are formed at positions along the tube wall 6.
Further, screw holes 40, 4 for fixing the converter 27 are provided outside the through holes 39, 39 for shielding.
0, ... Are formed.

On the other hand, as shown in FIG. 3, on the back surface side of the printed wiring board 25, similarly to the front surface side, a land portion 37b formed around the through hole 36 for connecting the central conductor,
A rectangular waveguide connection portion 38b is provided. Further, the land portion 37b and the waveguide connecting portion 38b are further added.
A portion 41 in which the conductor is linearly removed is formed so as to connect with each other. In this portion 41, one end is connected to the land portion 37b and the other end is located at the center point of the waveguide connecting portion 38b. The line 42 is formed.

Therefore, as shown in FIG. 1, one end of the printed wiring board 25 sandwiched between the upper case 33 and the lower case 34 extending horizontally with respect to the central conductor 24 extending vertically from the radial waveguide 28 is landed. It is fixed by the portion 37b, and the converter 27 is fixed to the other end of the printed wiring board 25 together with the upper case 33 and the lower case 34 by screwing. Then, the electromagnetic wave is generated by the radial waveguide 28.
From the center conductor 24, the microstrip line 42 of the printed wiring board 25, the waveguide 26 constituted by the upper case 33 and the lower case 34, and the converter 27.

In the planar antenna 20 of this embodiment,
Since the central conductor 24 and the waveguide 26 are connected via the printed wiring board 25, the printed wiring board 2
5 land portion 37a (37b) and waveguide connection portion 38a
By appropriately changing the dimension between (38b) and the mounting angle of the printed wiring board 25,
The position of the converter 27 with respect to the radial waveguide 28 can be freely set within a horizontal plane including the printed wiring board 25. Further, as is apparent from comparison with the conventional planar antenna 1 shown in FIG. 6, since the central conductor 24 and the waveguide 26 are connected via the printed wiring board 25 extending in the horizontal direction, the direction of the converter 27 is also conventional. You can convert from horizontal to vertical. That is, as compared with the conventional planar antenna in which the position and orientation of each member are fixed, the degree of freedom in the installation position or orientation of the converter is improved, so a suitable place where the converter does not interfere with other members, or It is possible to realize a planar antenna with a high degree of freedom that can be easily moved in any direction.

In the above structure, electromagnetic waves are transmitted from the radial waveguide 28 to the waveguide 26 and the converter 27 through the central conductor 24 and the microstrip line 42 on the printed wiring board 25. At this time, since the waveguide 26 is composed of the upper case 33 and the lower case 34, the waveguide 26 extends over both the upper side and the lower side of the printed wiring board 25. Therefore, if the shield through-holes 39, 39, ... In the present embodiment are not formed in the printed wiring board 25, there will be no waveguide inside the printed wiring board 25 by that thickness. As a result, transmission loss of electromagnetic waves occurs. However, in this embodiment, since the shield through holes 39, 39, ... Are formed at positions along the tube wall of the waveguide 26, the shield through holes 39, 39 ,.
Since it functions as if it were a part of the waveguide 26, it is possible to provide a planar antenna with less transmission loss.

Further, in this embodiment, the upper case 33 is used.
The lower case 34 and the lower case 34 are supporting means for supporting the printed wiring board 25 and the converter 27, and at the same time, the waveguide 26
Since it also has the function of
The total number of parts can be reduced and the structure can be simplified.

As another embodiment, the first waveguide is connected to the center conductor side while the second waveguide is connected to the converter side, and the first and second waveguides are connected to each other. May be connected via a printed wiring board. In that case, as shown in FIG. 4, two waveguide connecting portions 43a and 43b, which are similar to those of the printed wiring board 25 in the present embodiment, are provided symmetrically, and each of the waveguide connecting portions 43a and 43b is provided.
A large number of shield through holes 44a, 4a around 3b.
4b, ... Are formed, and the waveguide connecting portions 43a, 4a are formed.
The printed wiring board 46 provided with the microstrip line 45 so as to connect the center points of 3b may be used. When a planar antenna is constructed using this printed wiring board 46, the position of the converter with respect to the radial waveguide is indicated by a chain double-dashed line 27b from the position of the converter 27a facing the conventional waveguide 26, as shown in FIG. , Or 27c, that is, it can be freely set within the vertical plane including the printed wiring board.

In this embodiment, the printed wiring board 25 is a glass cloth-based epoxy resin plate with copper foil attached, but the printed wiring board 25 is not limited to this and other types of printed wiring boards may be used. May be. The position of the end of the microstrip line 42 in the waveguide connecting portion 38b does not necessarily have to be the center point of the waveguide connecting portion 38b. May be any position corresponding to. And the planar antenna 20
Although the above has been described as a satellite broadcast receiving antenna, it is needless to say that the present invention can be applied to a transmitting antenna. Furthermore, when using this planar antenna 20 outdoors,
A radome for protecting the radial waveguide 28 by preventing adverse effects such as rain and snow may be installed above the slot plate 21.

[0030]

As described above in detail, the first aspect of the present invention is as follows.
Since the planar antenna described in is configured such that the coaxial line and the waveguide are connected via the printed wiring board, the design dimensions on the printed wiring board can be changed or the mounting angle of the printed wiring board can be changed. By changing the position, the position of the converter with respect to the radial waveguide of the planar antenna can be freely set within the plane including the printed wiring board.
Furthermore, since the printed wiring board is arranged perpendicularly to the direction in which the coaxial line and the waveguide extend, the converter can be turned by 90 ° with respect to the conventional planar antenna. That is, compared to a conventional planar antenna in which the position and orientation of each member is fixed, it is possible to improve the degree of freedom in the installation position or orientation of the converter.
A suitable place where the converter does not interfere with other parts,
Alternatively, it is possible to realize a planar antenna having a large degree of freedom that can be easily moved in the direction.

Also, in the planar antenna according to the second aspect, as in the first aspect, the first waveguide connected to the coaxial line and the second waveguide connected to the converter are printed. Since the configuration is such that it is connected via the wiring board, the position of the converter with respect to the radial waveguide can be freely set within the plane including the printed wiring board by changing the design dimensions and mounting angle of the printed wiring board. You can That is, compared to the conventional planar antenna in which the position of each member is fixed, it is possible to improve the flexibility of the installation position of the converter. It is possible to realize a planar antenna with a high degree of freedom that can be easily moved.

Further, in the planar antenna according to the present invention, a through hole for shielding which penetrates the front and back of the printed wiring board and is covered with a plating layer is formed at a position along the tube wall of the waveguide. Therefore, when the electromagnetic wave is transmitted in the thickness direction inside the printed wiring board, the through hole for shielding functions as if it were a part of the waveguide, so that a planar antenna with less transmission loss is realized. be able to.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a planar antenna that is an embodiment of the present invention.

FIG. 2 is a plan view of a printed wiring board used for the planar antenna.

FIG. 3 is a rear view of the printed wiring board.

FIG. 4 is a plan view showing a printed wiring board used for a planar antenna that is another embodiment of the present invention.

FIG. 5 is a diagram showing a positional relationship of the converter with respect to the waveguide when the printed wiring board is used.

FIG. 6 is a vertical cross-sectional view showing a conventional planar antenna.

[Explanation of symbols]

 20 Planar antenna 21 Slot plate 22 Dielectric layer 23 Conductor plate 24 Center conductor (coaxial line) 25, 46 Printed wiring board 26 Waveguide 27, 27a, 27b, 27c Converter 28 Radial waveguide 37 Land portion 39, 44 For shield Through hole 42, 45 Microstrip line

Claims (3)

[Claims] 1. A radial waveguide formed by a slot plate, a conductor plate, and a dielectric layer interposed between the slot plate and the conductor plate, which are spaced apart from each other and face each other, and from the conductor plate side of the radial waveguide to the inside of the radial waveguide. A flat surface provided with a coaxial line, the tip of which is placed in proximity to the slot plate, a waveguide connected to the coaxial line, and a converter connected to the waveguide. In the antenna, the coaxial line and the waveguide are connected via a printed wiring board arranged perpendicularly to the extending direction of the coaxial line and the waveguide, and the coaxial wiring is connected to the printed wiring board. A planar antenna characterized in that a microstrip line is formed to connect a land portion to which is connected with a position corresponding to the inside of the waveguide. 2. A radial waveguide formed by a slot plate and a conductor plate which are spaced apart from each other and face each other, and a dielectric layer interposed therebetween, and from the conductor plate side of the radial waveguide to the inside of the radial waveguide. A flat surface provided with a coaxial line, the tip of which is placed in proximity to the slot plate, a waveguide connected to the coaxial line, and a converter connected to the waveguide. In the antenna, the waveguide includes a first waveguide connected to the coaxial line and a second waveguide connected to the converter, and the first and second waveguides are provided. The tubes are connected to each other via printed wiring boards arranged perpendicularly to the extending direction of the waveguides, and the printed wiring board corresponds to the inside of the first and second waveguides. Microstrip that connects positions Planar antenna, characterized in that the road has been formed. 3. The planar antenna according to claim 1, wherein the printed wiring board penetrates the front and back of the printed wiring board at a position along a pipe wall of the waveguide, and an inner wall surface is a plated layer. A planar antenna having a covered shield through-hole.