JPH08195610A - Cover for parabolic antenna - Google Patents

Abstract

PURPOSE: To eliminate the straining of the radio wave shield, reflecting plate, etc., that a conventional sheet-made cover and a parabolic antenna covered with the cover have. CONSTITUTION: The antenna cover covers the parabolic antenna 1 having the antenna reflecting plate 4 fitted to a base, a wave reception part 5 provided on the radio wave reflection path of the antenna reflecting plate 4, and a frame 8 which passes a sideward area of the antenna reflecting plate 4 at the time of radio wave incidence. The part which is formed of a water-repellent or air-permeable low-dielectric-constant sheet material and crosses the radio wave incidence path of the antenna reflecting plate 4 is so shaped that a plane is formed of the frame 8. Here, the frame 8 may be a box-shaped frame which is independent of an antenna main body and surrounds the antenna main body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna for transmitting information by radio waves for communication, broadcasting, etc., particularly gigahertz (GHz).
The present invention relates to a parabolic antenna that receives radio waves in a band, and more specifically, to a cover that covers the parabolic antenna.

[0002]

2. Description of the Related Art Parabolic antennas used for receiving satellite broadcasts are generally provided with an antenna cover for the purpose of avoiding adverse effects of wind and rain and snow. As the antenna cover, a molded cover made of a low dielectric constant plastic is generally used in the past. However, such a molded cover is covered by moisture that has penetrated into the inside through a gap between the covers due to a temperature difference from the outside air. There is a problem that dew condensation occurs on the inner surface of the antenna and the reflection surface of the antenna reflector, and water droplets caused thereby cause diffuse reflection of radio waves. To avoid this problem, when the cover is completely sealed, the air inside the cover repeatedly expands and contracts as the temperature changes, resulting in a large change in the pressure inside the cover. It is not desirable because it will continue to give stress. Therefore, it is considered desirable that the antenna cover be made of a water-repellent material having air permeability.

Japanese Utility Model Laid-Open No. 60-82813 proposes a cover made of a sheet material (awning) for covering the antenna reflector. To explain the technique described in this publication in detail, a plurality of frames extending forward from the reflector are attached to the antenna reflector, and the tips of these frames are assembled to form a support structure for the cover. The sheet-shaped cover that entirely covers the support structure and the reflection plate is formed in a shape that fits the support structure including the reflection plate, that is, a substantially conical shape or a polygonal pyramid shape.

In Japanese Utility Model Laid-Open No. 59-25808, there is disclosed a plate material in which an acrylic resin film is laminated on a PMMA plate and a fluorine resin film layer is further provided on the acrylic resin film via a heat-reactive adhesive film. There has been proposed a parabolic antenna cover formed by forming a fluorine resin film layer as an outer surface into a substantially hemispherical state.

[0005]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
The sheet-shaped cover described in Japanese Patent No. 82813 has the following problems. The conical or polygonal pyramid-shaped cover extending from the reflector toward the radio wave incident path of the antenna reflector inevitably requires a seam or a fold line to be located on the radio wave incident path in order to form its shape. Therefore, the seams and the like become a factor of attenuation of an input signal (hereinafter sometimes simply referred to as shielding of radio waves) due to an increase in reflected radio waves. Since the frame constituting the cover support structure is fixed to the antenna reflector, this frame is also located on the radio wave incident path, and the frame itself becomes a factor of shielding radio waves. Incidentally, although the above-mentioned publication proposes that the frame is made of a material having a low dielectric loss, even if the frame is made of such a material, the existence of the frame itself is a factor of shielding radio waves. There is no difference. Since the frame has a structure of being fixed to the antenna reflection plate, a load applied to the cover such as snow and wind is transmitted to the antenna reflection plate as it is, and the shape of the reflection plate is easily distorted.

Further, the parabolic antenna cover described in Japanese Utility Model Laid-Open No. 59-25808 has the following problems. The fluororesin layer on the outer surface is used mainly for the purpose of sliding snow and the like. Since it is not porous and has no water vapor permeability, radio interference due to dew condensation is likely to occur. In order to form a hemispherical shape, a relatively large vacuum container having at least one side of the antenna diameter or more, or a hemispherical male / female mold is required, which makes the manufacturing facility large and complicated. . For example, if a molding method that requires a mold is adopted, it is necessary to raise a dedicated mold for models with different antenna diameters. Also, the process itself is complicated and a special line design is required for mass production. Although no special structure for supporting the cover is described, it is considered that the shape is maintained by the strength of the PMMA layer itself, which is defined to have a thickness of 1 to 5 mm, and that the PMMA layer is fixed to the antenna by covering it later. Therefore, the load due to snow or wind is transmitted to the antenna reflection surface, and the hemispherical body is rejected. Since the contact angle with the horizontal plane is very small near the top, snow is likely to occur. Although the interfacial lubricity of the fluorine-based resin is great, especially when the outdoor use is for a long period of time, dust and dirt are likely to be accumulated and the lubricity tends to be lowered.

Therefore, an object of the present invention is to provide a sheet-shaped parabolic antenna cover which can solve the above problems.

[0008]

In order to achieve the above technical object, the parabolic antenna cover of the present invention is provided with an antenna reflector attached to a base and a radio wave reflection path of the antenna reflector. An antenna cover for covering a parabolic antenna having a received wave receiving section and a frame passing through a side area of a radio wave incident path of the antenna reflector,
It is made of a water-repellent and air-permeable low dielectric constant sheet material, and a configuration is adopted in which a portion of the antenna reflection plate that crosses the radio wave incident path has a shape in which a flat surface is formed by the frame.

Further, in the parabolic antenna cover of the present invention, the antenna reflection plate attached to the base formed of the housing having the electric circuit built therein and the wave receiving portion provided in the radio wave reflection path of the antenna reflection plate. An antenna cover for covering a parabolic antenna having and a box-shaped frame forming a side wall that does not hinder the radio wave reflection path of the antenna reflector surrounding the parabolic antenna, the water-repellent and air-permeable low dielectric constant sheet material It is also possible to adopt a configuration in which the portion of the antenna reflection plate that crosses the radio wave incident path has a shape that forms a plane by the frame.

Some parabolic antennas, such as a radial line slot system and a helical coil system: a stripline system, are called flat type antennas that do not have a conspicuous wave receiving portion. Then this is also included. Hereinafter, the function and effect of the present invention, other objects, etc. will be understood by referring to the following examples.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings. 1 to 4 show a first embodiment of the present invention. 1 shows the parabolic antenna covered with a cover, FIGS. 2 and 3 show the parabolic antenna with the cover removed, and FIG. 4 shows only the parabolic antenna cover. In particular, referring to FIGS. 2 and 3, the parabolic antenna 1 has a column 3 standing upright on a plate 2, and an antenna reflector 4 is attached to the upper end of the column 3. A wave receiving portion 5 is arranged in front of the antenna reflecting plate 4 so as to face the radio wave reflection path of the reflecting plate 4, and the wave receiving portion 5 is attached to the lower end of the reflecting plate 4 via an arm 6. There is.

The antenna 1 has a frame 8 fixed to the support column 3 via a ring 7. The frame 8 has a reverse U-shaped first pipe 9 arranged on the rear surface 4 a side of the reflection plate 4 and extending in the up-down direction. The upper end of the first pipe 9 is located directly above the upper end of the reflection plate 4. The curved portion 9a is positioned adjacent to the side of the back surface 4a of the reflection plate 4, and the lower end 9b is fixed to the ring 7 by welding or the like.
As is clear from FIG. 3, an imaginary plane formed by the character-shaped first pipe 9 is arranged in a region immediately behind the reflector 4 and the pillar 3, that is, in a position where it does not interfere with these elements 4 and 3 as much as possible. There is.

The frame 8 also has an inverted U-shaped second pipe 10 arranged in the front area of the reflector 4. The upper end of the second pipe 10 is fixed to the upper end of the first pipe 9, and as apparent from FIG. 3, the second pipe 10 extends obliquely downward from just above the reflection plate 4, and its lower end 10a has a wave receiving portion. It is located just before 5. The curved portion 10b of the second pipe 10 is arranged so as to surround the upper half of the reflection plate 4. That is, the second pipe 10 is arranged adjacent to the side of the radio wave incident path so as not to interfere with the radio wave incident path of the reflection plate 4.

A pair of lower ends 10a, 10 of the second pipe 10
a is connected by a horizontal pipe 11, and the ring 7
Are connected to the upper ends of a pair of inclined pipes 12 that extend obliquely downward toward the bottom of the ring pipes 7.
It is connected to. Reference numeral 13 shown in FIGS. 2 and 3 is a reinforcing horizontal pipe, and the lower ends of the first and second pipes 9 and 10 are connected by the horizontal pipe 13.

FIG. 4 shows a cover 1 for the parabolic antenna 1.
4 is shown. As is clear from the figure, the upper portion 14a of the cover 14 is formed in a shape that conforms to the three-dimensional shape formed by the curved portion 9a of the first pipe 9 and the curved portion 10b of the second pipe 10 of the antenna 1, The lower part 14b is the upper part 14
It has an opening 14c formed in a shape that extends downward from the lower end of a as it is and opens downward. The lower edge of the cover 14 is folded back and sewn, and the closing cord 15 is inserted. Further, a pair of tightening strings 16 and 17 are attached to the lower end of the upper portion 14a and the upper end of the lower portion 14b of the cover 14 at positions corresponding to the back surface of the antenna 1, respectively. At least the portion (14d) forming the plane of the cover 14 is made of a water-repellent and air-permeable sheet material, and its specific material will be described in detail later, but forms the above-mentioned three-dimensional shape. At this time, the three-dimensional sewing is performed so that the seam comes to the portion that comes into contact with the frame 8.

The method of mounting the cover 14 shown in FIG. 4 will be described. The cover 14 is covered over the parabolic antenna 1 with the opening 14c widened and then pulled downward to firmly mount the cover 14 and then the closing cord. Opening 14c at 15
Narrow down and tie. As a result, the cover 14 completely encloses the antenna 1 in a state where the cover 14 is squeezed at the ring 7. In addition, the binding cords 16 and 17 are tied together to remove the slack of the cover 14 (see FIG. 1). This allows
The front surface 14d of the cover 14, which crosses the radio wave incident path of the reflector 4, is in a state of being supported by the second pipe 10, that is, a flat state along an imaginary plane formed by the second pipe 10. Further, in some cases, like 23a, 23b, and 23c in FIG. 5, which will be described later, fixing cords are also provided inside the cover and are tied to the frame, respectively, so that the cover can be more firmly fixed. The position and number of internal fixing strings can be arbitrarily set together with the shape of the cover.

FIG. 5 shows a modification of the parabolic antenna 1 cover. The cover 20 shown in FIG. 5 has a basic shape as shown in FIG.
The cover 14 has an upper portion 20a, a lower portion 20b, and a lower end opening 20c, which have the same shape. Although not shown, the cover 20 is also provided with the closing cord 15 and the tightening cords 16 and 17 of the cover 14 shown in FIG. In the cover 20 of FIG. 5, a cut 20d extending greatly upward from the opening 20c is formed in a portion corresponding to one side of the back surface of the antenna 1, and the cut 20d is sandwiched between the one side and the other side. A hook tape 21 and a loop tape 22 are provided in each.

When the cover 20 is attached to the antenna 1, the cover 20 is opened at the cut 20d,
After mounting, the tapes 21 and 22 are engaged with each other to close the cut 20d, and then, similarly to the cover 14 of FIG. 4, narrowing and tightening are performed by a closing string and a tightening string. The form of the cover 20 after being attached to the antenna 1 is the same as that of the cover 14 of FIG. 4, and thus the description thereof will be omitted.

6 and 7 show a second embodiment of the present invention. FIG. 6 shows the parabolic antenna with the cover removed, and FIG. 7 shows the parabolic antenna covered with the cover. Referring to FIG. 6, parabolic antenna 3
Reference numeral 0 has a column 32 standing upright on a plate 31, and a casing 33 having a rectangular cross section is fixedly attached to the upper end of the column 32. Inside the casing 33, an electric circuit such as a power source and a converter (not shown) is housed, and an antenna reflection plate 34 is attached to the upper wall of the casing 33. The wave receiving portion 35 is provided on the front wall of the casing 33.
Is attached via the arm 35a.

The antenna 30 has a frame similar to the antenna 1 of the first embodiment, and a frame 36 provided on the antenna 30 has an inverted U-shaped first frame and is arranged in front of the reflector 34. It has first and second pipes 37 and 38.
The lower ends 37a and 37a of the first pipe 37 are
The curved portion 37b is fixed to the front portion of the upper wall of the casing 33.
Are arranged so as to be adjacent to the side of the reflection plate 34, and the uppermost end of the curved portion 37b is located directly above the reflection plate 34. That is, the curved portion 37b is arranged so as to surround the upper half of the reflection plate 34, and thus the first pipe 37a is similar to the second pipe 10 of the first embodiment in that the reflection plate 34b is arranged. It is arranged so as to be adjacent to the side of the radio wave incident path so as not to interfere with the radio wave incident path.

The second pipe 38 has its lower ends 38a, 38.
As is clear from FIG. 6, a is connected to the front ends of the pair of auxiliary pipes 39 extending forward from the front wall of the casing 33, and is obliquely upward from the lower end 38 a toward the upper end of the first pipe 37. The uppermost end of the second pipe 38 extends and is arranged at a position adjacent to the uppermost end of the first pipe 37. The curved portion 38b of the second pipe 38 is positioned adjacent to the side of this radio wave incident path so as not to interfere with the radio wave incident path of the reflection plate 4, like the curved portion 37b of the first pipe 37. It is arranged. In FIG. 6, reference numeral 40
Indicates a horizontal pipe, and the horizontal pipe 40 indicates the second pipe 38.
The lower ends 38a of the auxiliary pipe 39 are connected to each other and to the front end of the auxiliary pipe 39.

The cover 42 (see FIG. 7) for covering the antenna 30 of the second embodiment has the same shape and configuration as the cover 14 described in FIG. 4, and the closing cord 15 and the tightening cords 16, 17 of the cover 14 are provided. Since the same closing cord (not shown) and tightening cords 43, 44 are provided, further description will be omitted. The mounting of the cover 42 and the like are the same as those described with reference to FIG. 1, but the antenna 30 of the second embodiment is completely covered by the cover 42 including the casing 33, as is apparent from FIG. 7. .

Since the covers 14, 20, and 42 described above are made of the same material, the material of the cover 14 will be described below as a representative. The cover 14 may be made of a sheet material of expanded porous polytetrafluoroethylene (ePTFE) alone, but when ePTFE alone is considered to have weak strength, it is made of a sheet material having a reinforcing material added thereto. Is preferred. As is known, ePTFE has a property of water repellent porous low dielectric constant. The ePTFE preferably used in the present invention has an average pore diameter of 100 μm or less, preferably 0.01 to 10 μm, and a porosity of 30 to 95.
%, Preferably 50 to 95%, relative permittivity 1.0 to 2.1
5 is included. Regarding such a material, Japanese Patent Publication No. 51-18991 and Japanese Patent Publication No. 56-17216.
And US Pat. No. 3,953,566. In addition, a woven fabric in which expanded PTFE yarn is densely woven (which repels water but has air permeability) can also be used. When a reinforcing material is added, the reinforcing material is appropriately selected from synthetic organic polymer materials such as polyester, woven cloth, nonwoven cloth, knitted cloth, net, etc. made of inorganic material such as PTFE yarn or glass fiber. do it. If importance is attached to weather resistance, PTFE yarn, polyester, and glass fiber are preferable.

The sheet material composed of ePTFE and the reinforcing material preferably has a porosity of 30% or more, and more preferably 50% or more, in order to ensure air permeability. Is desirable. In order to obtain such a porosity, the reinforcing material may be arranged in a dot shape, a lattice shape, or a thread shape, or a woven or non-woven reinforcing material may be integrated with ePTFE while maintaining air permeability. The integration of the ePTFE and the reinforcing material may be performed by partially adhering the reinforcing material to one surface or both surfaces of the ePTFE or by passing between the heat rolls in the case of a thermoplastic reinforcing material.

According to the first and second embodiments described above, the sheet material for forming the covers 14, 20, 42 is made of the water-repellent material at least in the portion forming the plane of the cover. It is possible to prevent water from entering due to rain, snow, frost and the like. Further, since the sheet material has air permeability, the water content inside is discharged to the outside as water vapor, and it is possible to prevent shielding of radio waves due to dew condensation or the like. In addition, the front part of the cover that crosses the radio wave incident path of the reflector plate has no folds or seams and is flat due to the frame. It can be avoided. Further, by utilizing this flat front surface portion, for example, a design such as characters and pictures can be applied to the surrounding portion indicated by reference numeral 45 in FIG. When applying such a design, for example, a cotton material with the design is used as a reinforcing material for ePTFE, and the cover material is formed so that the design is located at a corresponding position.

Further, since the cover material of the present invention using ePTFE has a large water vapor permeability, the side surface and the back surface which are not present on the radio wave incident surface are made of a material other than the cover material, for example, weather resistant. It may be formed of a plastic sheet or a waterproof cloth, and it is possible to sufficiently prevent dew condensation, which does not depart from the gist of the present invention. Further, since the frames 8 and 36 are arranged so as not to traverse the radio wave incident paths of the reflectors 4 and 34, it is possible to shield the radio waves by the presence of the frames 8 and 36 without selecting a material having a low dielectric constant. There is no fear of doing it. Further, when the frames 8 and 36 are provided without being fixed to the reflection plates 4 and 34 as in the above embodiment, the load applied to the covers 14, 20 and 42 is not transmitted to the reflection plates 4 and 34. , Therefore
There is no fear of distorting the shape of the reflector as in the past.

Further, a third embodiment of the present invention is shown in FIGS. In this example, the cover is not fixed to the base or the support but to the antenna support. Figure 10 shows a parabolic antenna covered with a cover,
FIG. 11 shows the parabolic antenna with the cover removed, and FIG. 12 is a side view showing the connecting portion between the antenna body and the antenna support when the cover is removed. FIG.
Referring to FIG. 1, the parabolic antenna 60 has a pillar 62 provided upright on a plate 61, and an antenna reflector 64 is attached to an upper end of the pillar 62 via an antenna support 63. A wave receiving portion 65 is attached to the front of the reflection plate 64 via an arm 65a. The antenna 60 is a ring-shaped front frame pipe 66 arranged in the front area of the reflector 64,
And a ring-shaped rear frame pipe 67 arranged in the rear area of the reflection plate 64, both pipes are connected by a horizontal pipe 68, and the rear frame pipe 67 is connected to the antenna support 63 and the connection pipe 6.
They are connected at 9, 70.

A cover 71 (see FIG. 10) for covering the antenna 60 has a similar shape and structure to the cover 14 described in FIG. 4, and a connecting portion between the antenna support 63 and the connecting pipes 69, 70 by a tightening string 72. Is narrowed down, and the strut 62 is narrowed down by the tightening string 73.

In the case of the third embodiment in which the frame of the cover is fixed to the antenna support, compared with the case of fixing the frame of the cover to the antenna itself, the frame and its weight are received by the antenna support. However, it is necessary to increase the strength of the support tool, which increases the weight of the support tool itself. However, since the support itself and the framework can be disassembled and assembled, it is unlikely to cause a problem during installation.
On the other hand, when fixing the frame to the antenna itself, it is necessary to increase the strength of the antenna main body, which may increase the weight of the antenna main body and distort the reflection surface, and maintain the accuracy of the antenna main body. From this point, disassembly and assembly cannot be performed, so there is a problem that handleability during installation is poor. Therefore, when the frame and the cover are directly attached to the reflector, the antenna reflector preferably has a relatively small diameter.

Further, a fourth embodiment of the present invention is shown in FIGS.
Shown in In this example, the framework structure that supports the cover is independent of the antenna body. 8 and 9 show a parabolic antenna covered with a cover, FIG. 8 is a perspective view, and FIG. 9 is a side view. Referring to FIG. 9, a parabolic antenna 50
Has a support plate 53 erected on a fixed casing 52 having a short cross section on a pedestal 80. Inside the casing 52, electric circuits such as a power source and a converter are housed (not shown). . An antenna reflector 54 is attached to the upper end of the support plate 53. The reflector 54 is adjusted to an arbitrary inclination by the turnbuckle 55. A wave receiving portion 56 is attached to the front wall of the casing 52 via an arm 56a.

A box-shaped frame 57, which can form a side wall surrounding the antenna, is provided around the antenna 50 independently of the antenna 50. Of course, the side wall formed in this case does not obstruct the radio wave reflection path of the reflector 54. That is, in the frame 57, the rear side of the antenna reflection plate 54 has a height higher than the highest position that the upper end of the reflection plate 54 can take, and the front side of the reflection plate 54 also has a maximum inclination when the reflection plate 54 is inclined. It has a height lower than the lowest position that can receive radio waves.

The antenna cover 58 is attached to the frame 57, and the ceiling surface (that is, the surface that crosses the radio wave incident path of the antenna reflection plate 54) is formed in a flat state. In this case, the cover 58 is made of a single sheet of expanded porous polytetrafluoroethylene (ePTFE) or a sheet material having a reinforcing material added thereto as in the case of the first and second embodiments. Further, as in the case of the first and second examples, the ePTFE (containing) sheet is not the entire sheet,
It may be only a plane that crosses the radio wave incident path of the reflector.
FIG. 9 shows a case where an ePTFE (containing) sheet is used only on the plane, and the side wall portion in this case is a box-shaped one made of, for example, a metal or plastic plate. It is clear that the same effects as those of the first and second embodiments are also produced in the fourth embodiment.

[0033]

As is apparent from the above description, according to the present invention, since the seam and the like of the cover and the frame are not located on the radio wave incident path of the antenna reflection plate, the existence of these seam and the frame is eliminated. It is possible to avoid the accompanying electromagnetic wave shielding. Further, since the frame is not fixed to the reflection plate, the reflection plate is not affected by the load applied to the cover.

[Brief description of drawings]

FIG. 1 shows a first embodiment of the present invention, and is a perspective view of a parabolic antenna covered with a cover.

FIG. 2 shows the first embodiment of the present invention, and is a perspective view of the parabolic antenna with a cover removed.

FIG. 3 is a side view of the parabolic antenna shown in FIG.

FIG. 4 is a perspective view of a parabolic antenna cover showing the cover shown in FIG. 1 as a single body.

FIG. 5 is a perspective view showing a modified example of the parabolic antenna cover.

FIG. 6 shows a second embodiment of the present invention and is a perspective view of the parabolic antenna with a cover removed.

FIG. 7 shows a second embodiment of the present invention, and is a perspective view of a parabolic antenna covered with a cover.

FIG. 8 shows a fourth embodiment of the present invention and is a perspective view of a parabolic antenna covered with a cover.

FIG. 9 shows a fourth embodiment of the present invention and is a side view of the parabolic antenna with a cover removed.

FIG. 10 shows a third embodiment of the present invention and is a perspective view of a parabolic antenna covered with a cover.

FIG. 11 shows a third embodiment of the present invention and is a side view of the parabolic antenna with a cover removed.

12 is an enlarged view showing a connecting portion between the antenna body and the antenna support in FIG.

[Explanation of symbols]

 1 Parabolic Antenna 2 Plate 3 Post 4 Reflector 4a Reflector Rear 5 Wave Receiving Section 6 Arm 7 Ring 8 Frame 9 1st Pipe 9a 1st Pipe Bending 9b 1st Pipe Lower 10 10 2nd Pipe 10a 2nd Pipe Lower 10b 10th 2 Pipe curved part 11 Horizontal pipe 12 Inclined pipe 13 Reinforcing pipe 14 Cover 14a Cover upper part 14b Cover lower part 14c Cover lower end opening 14d Cover flat part 15 Closing string 16, 17 Tightening string 20 Cover 20a Cover upper part 20b Cover lower part 20c Cover lower end Opening 20d Cover break 21, 22 Tape 23a, 23b, 23c Internal fixed string 30 Parabolic antenna 31 Plate 32 Strut 33 Casing 34 Reflector 35 Wave receiver 35a Arm 36 Frame 37 First pipe 37a First pipe lower end 3 b 1st pipe curved part 38 2nd pipe 38a 2nd pipe lower end 38b 2nd pipe curved part 39 Auxiliary pipe 40 Horizontal pipe 42 Covers 43, 44 Tightening string 45 Display part such as a character figure 50 Parabolic antenna 51 Plate 52 Casing 53 Strut 54 Reflector 55 Turnbuckle 56 Wave Receiving Section 56a Arm 57 Box Frame 58 Cover 60 Parabolic Antenna 61 Plate 62 Strut 63 Antenna Supporting Tool 64 Reflector 65 Receiving Section 65a Arm 66 Front Frame Pipe 67 Rear Frame Pipe 68 Horizontal Pipe 69 , 70 Connection pipe 71 Cover 72, 73 Tightening string 80 Pedestal

Claims (7)

[Claims] 1. An antenna reflector attached to a base,
A wave receiving portion provided in a radio wave reflection path of the antenna reflector,
An antenna cover for covering a parabolic antenna having a frame passing through a side area of a radio wave incident path of the antenna reflector, the cover being made of a water-repellent and breathable low dielectric constant sheet material, and the radio wave incident path of the antenna reflector. An antenna cover, characterized in that a portion that intersects with is shaped to form a plane by the frame. 2. The antenna cover according to claim 1, wherein the base is formed of a housing having an electric circuit built therein, and has a shape integrally covering the parabolic antenna main body including the housing. 3. The antenna cover according to claim 1, wherein a slack preventing unit is provided on a back surface portion covering the back surface side of the antenna reflector. 4. The antenna cover has a bag-like shape having an opening that opens downward and a narrowing means that narrows the opening, and the opening is formed after the antenna cover is covered with the frame through the opening. The antenna cover according to claim 2, wherein a portion is narrowed down by the narrowing-down means. 5. A parabona antenna having an antenna reflection plate attached to a base formed of a housing having an electric circuit built therein and a wave receiving portion provided in a radio wave reflection path of the antenna reflection plate, and the antenna surrounding the parabona antenna. An antenna cover that covers a box-shaped frame that can form a side wall that does not obstruct the radio wave reflection path of the reflection plate, and is made of a water-repellent and air-permeable low dielectric constant sheet material, and the radio wave incidence path of the antenna reflection plate is An antenna cover, wherein a crossing portion has a shape forming a flat surface by the frame. 6. The antenna cover according to claim 1, wherein the sheet material is made of porous expanded polytetrafluoroethylene. 7. The antenna cover according to claim 6, wherein the porous sheet material is composed of the expanded polytetrafluoroethylene and a reinforcing material attached thereto.