JPH07326924A - Plane antenna - Google Patents

Abstract

PURPOSE:To form a plane antenna hardly causing crack and deformation, etc., of a cover, hardly receiving the interference of communication and capable of coping with the various kinds of installation forms without changing the appearance of the entire antenna. CONSTITUTION:To the upper surface 11a of a metallic substrate 11, two antenna elements 30 for forming a diversity antenna with the substrate 11 as a ground conductor are attached with a prescribed interval. The substrate 11 is freely rotatably supported inside an antenna cover by inserting the tip of pins 19 projectingly provided on both ends to pin holes 37 inside the opening part 35 of the antenna cover 35 formed of a synthetic resin and fixed to an optional angle position by tightening screws 40. The upper surface 35a of the antenna cover 35 is formed so as to be swelled in the shape of a curved surface and covers the upper surface of the substrate 11 and the antenna elements 30.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a planar antenna which constitutes a diversity antenna with a plurality of antenna elements.

[0002]

2. Description of the Related Art A planar antenna has a structure in which plate-like antenna elements are arranged on a grounding conductor plate with a gap, and the resonance frequency thereof is determined by the size of the antenna element, the distance from the grounding conductor plate, etc. As compared with the size of the antenna element, the larger the area of the grounding conductor plate is, the less the adverse effect of the external metal article on the characteristics is.

In such a planar antenna, in order to protect the antenna element and maintain its characteristics, for example, an actual flat antenna 5-
As disclosed in Japanese Patent No. 48415, the surface is covered with a flat box-shaped synthetic resin cover (radome).

[0004]

By the way, in order to realize more stable communication with such a planar antenna, a plurality of antenna elements are arranged in a line, and a diversity antenna is constructed with these antenna elements. It is necessary to use a long cover in the direction in which the antenna elements are arranged.

Further, in the planar antenna, the area of the grounding conductive plate needs to be sufficiently larger than the size of the antenna element, so that a cover having a flat surface and a wide surface must be used as described above.

However, when a cover having a flat surface covering the antenna element and having a wide surface is used, there arises a problem that the cover is cracked or deformed by a strong external force.

If the height at which the antenna is installed is low, things will be placed on this flat cover,
There was also a risk that the passage of radio waves would be obstructed.

Further, considering that the conventional planar antenna having the antenna element fixed in the cover is used at various installation places, the radiation characteristics (directivity and launch angle) of the antenna are compared with the direction of the communication partner. In order to match with the above, it is necessary to change the mounting angle of the entire cover with respect to the installation location.

For example, when mounting the antenna on a wall surface, the mounting angle of the entire cover is changed depending on the mounting height position or the like, or even when the antenna is mounted on the upper surface of the housing of the equipment, Depending on the height to be installed and the situation around the equipment, the installation angle of the entire cover must be changed, the installation form cannot be unified, the workability and versatility are lacking, and the appearance is also unfavorable. turn into.

The present invention solves such a problem, the cover is unlikely to be cracked or deformed, communication is less likely to be disturbed, and the appearance of the entire antenna can be changed to various installation modes without making a large change. The purpose is to provide a planar antenna that can be used.

[0011]

In order to solve the above-mentioned problems, the planar antenna of the present invention is attached to a metal substrate and one surface side of the substrate with a predetermined gap, and constitutes a diversity antenna together with the substrate. And a plurality of plate-shaped antenna elements, one surface of which is outwardly bulged outward in a curved shape, and an opening is formed on the opposite surface side of the antenna element. And an antenna cover made of synthetic resin for covering the plurality of antenna elements on the side of the bulged one surface, and an angle varying means for varying the support angle of the substrate with respect to the antenna cover in the antenna cover.

[0012]

As described above, in the planar antenna of the present invention, the one surface side of the substrate and the plurality of antenna elements attached to the one surface side are covered by the antenna cover made of synthetic resin which bulges outward in a curved shape. Moreover, the support angle of the substrate with respect to the antenna cover can be changed.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. 1 to 7 show an external appearance and an internal structure of a planar antenna 10 of one embodiment which is used by being attached to a substantially flat surface such as an upper surface of a device or a ceiling.

As shown in these figures, the planar antenna 10 has a substrate 11 and a substrate 2 mounted on the substrate 11.
It is configured by one antenna element 25 and an antenna cover 35 that covers the upper surface of the substrate 11 and the antenna element 25.

The substrate 11 is made of a metal material and is formed in an oval shape with both ends having an arc shape.
Two circular holes 12, 12 are provided at predetermined intervals along the length direction of the substrate. Further, around each circular hole 12, a screw hole 13 for screwing and fixing the antenna element 20 to the upper surface 11a of the substrate 11 is provided.

Bending plates 14, 14 formed in a stepwise downward shape are provided at the central portions of the arcuate outer circumferences of both ends of the substrate 11 so as to face each other.

Each bent plate 14 extends downward from the edge of the substrate 11 at a right angle by a predetermined length, and a first vertical portion 15 extends outward from the lower end of the first vertical portion 15 in parallel with the substrate 11. And a second vertical portion 17 extending downward from the tip of the horizontal portion 16 by a predetermined length.

On the lower surface 11b side of the substrate 11, each bending plate 1 is provided.
The pin support plates 18, 18 facing the respective vertical portions 15 in parallel at a position separated from the first vertical portion 15 by a predetermined distance.
Is installed.

Between the first vertical portion 15 of each bending plate 14 and the pin support plate 18, round bar-shaped pins 19, 19 are provided.
It is supported in parallel with 1.

Each pin 19 is formed in the shape of a round bar having a predetermined diameter, and has a large-diameter portion 19a having a larger diameter than the other portions in the middle thereof. Each pin 19 extends in the length direction of the substrate 11 with one end of the pin 19 projecting outward from the first vertical portion 15 and the other end projecting from the pin support plate 18 inward of the substrate 11. It is supported so that it can slide along, and by the action of a spring, etc. (not shown),
The large-diameter portion 19a is urged in a direction in which the large-diameter portion 19a abuts against the first vertical fifteenth inner surface side, that is, in a direction in which one end side of the pin projects outward from the first vertical portion 15.

The protruding length of each pin 19 from the first vertical portion 15 is set to be longer than the length of the horizontal portion 16.

As shown in FIGS. 5 and 7, the second vertical portion 17 of each bent plate 14 is formed along an arc centered on the pin 19 supported by the first vertical portion 15. The circular arc grooves 20 and 20 are formed respectively.

Each hole 1 is formed on the upper surface 11a of the substrate 11.
Antenna elements 25,
25 is screwed. As shown in FIG. 6, each antenna element 25 includes a metal first disc 26 and a first disc 2
The second disc 27 made of metal and having a diameter smaller than that of the first disc 26 and arranged at a concentric position above the first disc 26 with a predetermined gap.
And attached to the lower surface of the first disc 26, and the outer skin 2
8a is electrically connected to the first circular plate 26, and the core wire portion 28b
Is a coaxial connector 28 electrically connected to the second disc 27.
And a short pin 29 for electrically connecting the second disk 27 and the first disk 26 to match the antenna,
It is integrally configured with a synthetic resin cylinder 30 that covers the second circular plate 27.

The metal substrate 11 is electrically connected to the first disc 26 of each of the antenna elements 25 screwed together, and together with the first disc 26 forms a ground plane of the planar antenna 10. In addition, the coaxial connector 28 of each antenna element 25 has the bottom surface 11 b of the substrate 11 through the holes 12 and 12.
The cable connection from the communication equipment is made possible.

The frequency characteristic and the radiation characteristic of each antenna element 25 thus mounted on the substrate 11 are
It is known that it is determined by the distance between the disc 27 and the ground plane, the area (diameter) of the second disc 27, the size of the ground plane, etc., but here the resonance frequency of each antenna element 25 is ,
For example, PHP communication (personal handyphone communication)
The dimensions of each part should be such that the radiation characteristics (directivity) of the horizontal surface are uniform in all directions and the radiation characteristics (launch angle) of the vertical surface is approximately 15 °. It is assumed to be predetermined.

Further, the distance between the two antenna elements 25, 25 is set to such a size that stable diversity communication can be performed without causing mutual interference in the frequency band.

Thus, the two antenna elements 2 are provided on the upper surface side.
The substrate 11 to which 5 is attached is supported by the antenna cover 35.

The antenna cover 35 is made of synthetic resin such as reinforced plastic and is integrally molded so that the inside thereof is hollow and the upper surface 35a bulges upward in a curved shape. On the lower surface side of the antenna cover 35, there is provided an opening 35b which is larger than the outer shape of the substrate 11 and which is opened in a substantially similar oval shape.

A plurality of screw fastening portions 36 for attaching the antenna cover 35 to a substantially flat surface are provided on the straight portion of the inner edge of the opening 35b.

Further, pin holes 37, 37 having a hole diameter capable of receiving the pin 19 projecting to the side of the substrate 11 are formed in the arc-shaped central portion of the inner wall of the opening 35b of the antenna cover 35. It is drilled horizontally outward along the length direction.

Cylindrical bosses 38, 38 slightly projecting inward are provided directly below the pin holes 37, 37, and the end face of each boss 38 is provided with a pin 19 of the substrate 11 and an arc groove. Screw holes 39, 39 having a predetermined depth are provided parallel to the pin holes 37, 37 at a lower position apart from each pin hole 37 by a distance equal to the distance between the pin holes 37.

The substrate 11 is supported so as to close the opening 35b of the antenna cover 35. That is, the substrate 1
The pins 19 protruding from both ends of the pin 1 are inserted into the pin holes 37, 37 of the antenna cover 35.
The antenna cover 35 with the line connecting 9 and 19 as the center of rotation
It is rotatably supported inside.

The substrate 1 for the antenna cover 35
1 is mounted with the pins 19 pushed inward so that the entire substrate 11 is opened in the opening 35b of the antenna cover 35.
Then, the pins 19 and 19 are projected outward and inserted into the pin holes 37 and 37 of the antenna cover 35.

Then, the circular arc groove 20 is inserted from the center side of the lower surface of the substrate 11 and the screws 40, 40 are tightened in the screw holes 39, 39, respectively. It is fixed to the antenna cover 35 in the horizontal state as shown in 6.

FIG. 8 shows a state in which the planar antenna 10 thus constructed is attached to the upper surface 50a of the plate 50. The flat antenna 10 is fixed to the plate 5 by the screws 51.
The screwing portion 36 is screwed from the side of the lower surface 50b of No. 0 and is fixed to the upper surface of the plate body 50. A coaxial cable (not shown) from a communication device that uses the planar antenna 10 as a diversity antenna for communication is connected to the coaxial connector 28 of each antenna element 25.

The planar antenna 1 thus mounted
The antenna cover 35 of 0 has a shape that bulges upward in a curved surface, and therefore, compared with a cover having a flat upper surface,
It can withstand strong external force from above and is less likely to crack or deform. Further, even when the antenna cover 35 is horizontally installed in this manner, the upper surface thereof is a curved surface, so that an object cannot be stably placed on the cover, and the communication object is less likely to be disturbed by the object placed. .

In this figure, the substrate 11 is previously fixed inside the antenna cover 35 at a substantially horizontal support angle, and the launch angle α of the antenna in this case is approximately 15 ° in all directions as described above. It has become.

Here, when it is desired to lower the launch angle of the front side (or the rear side) of the planar antenna 10 with respect to the communication partner side in an installation condition in which the plate body 50 is located at a higher position, If the screws 40, 40 are loosened, the substrate 11 is rotated with respect to the antenna cover 35 until it is tilted, the screws 40, 40 are tightened, and then fixed on the upper surface of the plate body 50 as shown in FIG. The launch angle α can be made lower (approximately 0 °) on the front side of the antenna. The adjustment of the support angle can be arbitrarily performed between the state shown in FIG. 9 and the state symmetrical with FIG. 9 (not shown) including the horizontal state shown in FIG. 8 according to the installation situation.

Even when the radiation characteristic is changed in this way, the mounting state of the entire planar antenna does not change,
The same appearance can be applied to various installation locations.

[0040]

Other Embodiments In the above embodiments, each antenna element 25 has the first circular plate forming the ground plane so that it can be used alone as a planar antenna. However, the metal plate corresponding to the second circular plate may be directly supported on the substrate 11.

Further, in the above-described embodiment, the pins 19, 19 protruding outward from both ends of the substrate 11 are attached to the antenna cover 35.
Is inserted into the pin holes 37, 37 provided inside the opening of the board to support the board rotatably with respect to the antenna cover, and the board is supported by loosening and tightening the screws 40, 40. Although the angle can be changed and fixed, the method of supporting the substrate and the method of changing the supporting angle are not limited to this embodiment, and various modifications can be considered. For example, if the pin 19 and the pin hole 37 of the above-described embodiment are omitted and the arc groove 20 is simply changed to a round hole, not only the support angle of the substrate is adjusted but also the substrate is supported by operating the screws 40 and 40. You can do that.

In the above embodiment, the support angle of the substrate is continuously variable within a predetermined angle range. However, the support angle can be changed at predetermined intervals (for example, 5 °). Good. In this case, as shown in FIG. 10, a plurality of recesses 55 are provided at a predetermined angular interval on either the end side of the substrate or the inner wall side of the antenna cover, and the other side is provided in the recess direction. A convex portion 56 that is urged to engage with each concave portion 55 is provided, and the convex portion 56 is provided in one of the plurality of concave portions 55.
In the engaged state, the substrate and the antenna cover are fixed with screws or the like, or the fixing means such as screws is not particularly provided, and only the engagement between the concave portion 55 and the convex portion 56
You may make it maintain the support angle with respect to a board | substrate.

Further, in the above embodiment, the support angle of the substrate is adjusted by the screw operation on the lower surface side of the substrate in advance, and then the planar antenna is installed. However, for example, the screw is applied from the outer surface side of the antenna cover. The support angle of the substrate may be made variable by moving in and out of the antenna, etc. By doing so, the radiation characteristic of the antenna can be changed according to the installation condition after the antenna cover is attached.

In the above embodiment, the case where the radiation characteristic of the antenna element is mainly in the circumferential direction has been described, but the present invention is similarly applied to the case where the radiation characteristic is in the axial direction of the antenna element. it can.

[0045]

As described above, in the planar antenna of the present invention, the one surface of the substrate and the plurality of antenna elements mounted on the one surface side are provided by the antenna cover which bulges outward in the shape of a curved surface. Since it is covered, even if the covering surface is wide, it can withstand strong external forces, and since it is not possible to stably place articles on this antenna cover, it will interfere with the passage of radio waves There is little fear.

Further, since the support angle of the substrate by the antenna cover can be changed inside the antenna cover, the radiation characteristics of the antenna can be fixed in the most suitable direction for various installation places without changing the appearance of the installation. be able to.

[Brief description of drawings]

FIG. 1 is a plan view of an embodiment of the present invention.

FIG. 2 is a front view of an embodiment of the present invention.

FIG. 3 is a side view of an embodiment of the present invention.

FIG. 4 is a bottom view of an embodiment of the present invention.

FIG. 5 is an exploded perspective view of an embodiment of the present invention.

6 is an enlarged sectional view taken along the line AA of FIG.

FIG. 7 is an enlarged perspective view showing a main part of one embodiment.

FIG. 8 is an enlarged side view showing the installation state of the embodiment.

FIG. 9 is an enlarged side view showing a state where the support angle of the substrate according to the embodiment is changed and installed.

FIG. 10 is a schematic view showing a main part of another embodiment of the present invention.

[Explanation of reference numerals] 10 planar antenna 11 substrate 14 bent plate 19 pin 20 arc groove 25 antenna element 26 first disc 26 second disc 28 coaxial connector 35 antenna cover 37 pin hole 39 screw hole 40 screw

Claims (1)

[Claims] 1. A metal substrate, which is attached to one surface side of the substrate with a predetermined gap,
A plurality of plate-shaped antenna elements forming a diversity antenna together with the substrate, one surface side outwardly bulging in a curved shape, and an opening is formed on the opposite surface side, and the substrate is supported in the opening. An antenna cover made of synthetic resin for covering one surface side of the substrate and the one surface side of the plurality of antenna elements, and an angle varying means for varying the support angle of the substrate with respect to the antenna cover within the antenna cover. A planar antenna with and.