KR101769136B1 - Antenna for satellite - Google Patents

Abstract

An antenna for an artificial satellite according to an embodiment of the present invention includes a driving unit, a feeder provided on a central axis of the driving unit, and an antenna reflection plate which is composed of a plurality of ribs rotatably connected to the driving unit and a plurality of reflection sheet between the plurality of ribs. If the antenna reflection plate is folded, the plurality of ribs are stacked and the reflection sheet is maintained with a folded state. If the antenna plate is unfolded, the ribs rotate along the outer circumference of the driving unit and the reflection sheet is spread to be arranged around the feeder with a radial shape. Accordingly, the present invention can reduce the whole size of the artificial satellite and mount the artificial satellite in a narrow space of a satellite launch vehicle.

Description

Antenna for satellite

Field of the Invention [0002] The present invention relates to a satellite antenna, and more particularly, to an antenna for a satellite configured to be folded to be mounted in a narrow space of a satellite launch vehicle.

 Generally, an antenna is a wireless communication device for transmitting a radio wave to the outside or receiving an external radio wave.

In the case of a large-sized antenna, a curved parabolic reflector is provided for smooth and efficient reception of external radio waves. A feedhorn is installed at the focal point of the dish-type reflector to receive the reflected wave from the dish-type reflector and focus on the focus.

On the other hand, the antenna used in the space environment is launched into the ozone space while being mounted in a narrow space of the satellite launch vehicle. The size of the antenna reflector may vary depending on the output and frequency band of the amplifier. Generally, the antenna reflector is manufactured in the range of about 3m to 10m. It can be folded so that it can be stored in a narrow space inside the pairing of satellite projectile Should be designed.

Typically, the foldable reflector can be divided into a shell type, a mesh type, and a membrane type according to the material and the development method. These various types of folding reflectors are opened by various types of developing methods, and recently, antennas using a shape memory alloy or a springback have been developed.

In the case of motors and bearings, which are commonly used in the design of ground-driven parts, the application of harsh space environment requirements increases the cost of components at astronomical prices, thus creating constraints on the design. Therefore, there is a need for a technique capable of implementing a reliable folding mechanism while using inexpensive mechanical elements.

Korean Patent No. 1304358

SUMMARY OF THE INVENTION It is an object of the present invention to provide a satellite antenna that is improved in structure and deployment manner so as to be mounted in a narrow space of a satellite launch vehicle.

According to an aspect of the present invention, there is provided an antenna for a satellite, comprising: a driving unit; A feeder provided on a central axis of the driving unit; And an antenna reflector including a plurality of ribs rotatably connected to the driving unit and a plurality of reflective sheets provided between the plurality of ribs, wherein when the antenna reflector is unfolded, The ribs are stacked and the reflective sheet is held in a folded state, and when the antenna reflector is deployed, the ribs are rotated along the outer periphery of the driving portion, and the reflective sheet is unfolded and arranged in a radial fashion around the feeder .

The driving unit may include: a disc-shaped supporter configured to support the rib; A cylindrical guide portion provided at the center of the support portion; And an elastic member provided inside the guide portion, and the rib may be connected to the elastic member through the guide portion.

The guide portion may include: an outer cylindrical portion having a slit through which the rib is inserted; And an inner cylindrical portion provided inside the outer cylindrical portion, and the elastic member may be provided between the outer cylindrical portion and the inner cylindrical portion.

The elastic member may be a torsion spring having one end connected to the inner cylindrical portion and the other end connected to the rib.

The outer cylindrical portion alternately has a plurality of guide holes and a plurality of slits formed at different heights, and the guide holes and the slits are communicated with each other.

The rib can rotate along the slit by the elastic energy of the elastic member.

The support portion includes: a base plate coupled to the guide portion; A lift plate which abuts the ribs; And a height adjusting member provided between the base plate and the rising plate.

The height adjusting member may be a coil spring.

And a fixing device for connecting the feeder and the rib.

The fixing device includes: an electromagnet provided in the feeder; And a metal member provided on the rib and capable of magnet coupling with the electromagnet; And a damper member connecting the feeder and the rib to surround the metal member.

The rib may be folded toward the feeder when the metal member is magnetically coupled to the electromagnet, and may be extended away from the feeder when the metal member is disengaged from the electromagnet.

The ribs may be made of spring steel or a shape memory alloy material.

A ball plunger may be formed on one surface of each of the ribs.

Therefore, according to the antenna for artificial satellite according to the embodiment of the present invention, when the antenna is mounted on a satellite, the overall size of the satellite can be reduced and the satellite can be mounted in a narrow space of the satellite launch vehicle , The risk of failure in a space environment can be reduced.

1 is a perspective view showing a state in which an antenna reflector of a satellite antenna according to an embodiment of the present invention is deployed.
2 is a perspective view illustrating a state in which an antenna reflector of an antenna for a satellite according to the embodiment of the present invention is unfolded.
3 is a perspective view of a driving unit according to an embodiment of the present invention.
4 is a cross-sectional view of the driving unit of Fig.
5 is a view illustrating a fixing device according to an embodiment of the present invention.
FIG. 6 is a diagram illustrating an intermittent process of a fixing apparatus according to an embodiment of the present invention.
7 is a first operational state diagram illustrating a process of developing an antenna reflector of a satellite antenna according to an embodiment of the present invention.
FIG. 8 is a second operational state diagram illustrating a process of developing an antenna reflector of a satellite antenna according to an embodiment of the present invention.
FIG. 9 is a first view for explaining the operation of the driving unit when the antenna reflector of the antenna for artificial satellite according to the embodiment of the present invention is deployed. FIG.
FIG. 10 is a second diagram for explaining the operation of the driving unit when the antenna reflector of the antenna for satellite according to the embodiment of the present invention is deployed. FIG.
11 is a view illustrating a process of manufacturing a rib according to an embodiment of the present invention.

In order to fully understand the present invention, operational advantages of the present invention, and objects achieved by the practice of the present invention, reference should be made to the accompanying drawings and the accompanying drawings which illustrate preferred embodiments of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail with reference to the preferred embodiments of the present invention with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. In order to clearly explain the present invention, parts not related to the description are omitted, and the same reference numerals in the drawings indicate the same members.

Throughout the specification, when an element is referred to as " including " an element, it does not exclude other elements unless specifically stated to the contrary.

1 and 2, the satellite antenna 10 according to the embodiment of the present invention is improved in structure and deployment in order to be mounted on an artificial satellite accommodated in a narrow space of a satellite launch vehicle, A feeder 200, a reflection plate 300, a fixing device 400, and a tripod 500, and the like.

The antenna for artificial satellite 10 according to the embodiment of the present invention is characterized in that a feeder 200 is provided on the center axis of the driving part 100 and a plurality of antenna reflection plates 300 are rotatably connected to the driving part 100 A rib 310 and a plurality of reflective sheets 320 provided between the plurality of ribs 310.

The antenna for an artificial satellite according to an embodiment of the present invention is configured such that a plurality of ribs 310 are stacked when the antenna reflector 300 is unfolded and the reflection sheet 320 is held in a folded state, When the antenna reflector 300 is deployed, the rib 310 rotates along the outer periphery of the driving unit 100, and the reflection sheet 320 is unfolded and arranged in a radial fashion around the feeder 200.

Accordingly, in the antenna for artificial satellite 10 according to the embodiment of the present invention, the antenna reflector 300 is not deployed, that is, a plurality of ribs 310 are stacked, the reflection sheet 320 is folded, Since it can be mounted on satellites without being arranged, the overall size of the satellites can be reduced and the satellites can be mounted in a narrow space of the satellite launch vehicle.

The antenna for a satellite 10 according to an embodiment of the present invention may be configured such that when the satellite reaches the space orbit by the satellite launch vehicle, the antenna reflector 300 is not a separate electric driving element, The rib 310 can rotate along the outer periphery of the driving unit 100 and the reflective sheet 320 can be unfolded and arranged in a radial fashion around the feeder 200, The risk of failure in the environment can be reduced.

Hereinafter, the configuration of the artificial satellite antenna 10 according to the embodiment of the present invention will be described in detail.

The driving unit 100 may be provided at the center of the antenna 10. The feeder 200 and the antenna reflector 300 may be connected to the driving unit 100. The driving unit 100 may rotate the antenna reflector 300. [ The detailed structure of the driving unit 100 will be described with reference to FIGS. 3 and 4. FIG. 3 is a perspective view of the driving unit 100 with the top plate removed, and Fig. 4 is a sectional view of the driving unit 100. Fig.

3 and 4, the driving unit 100 includes a disk-shaped supporting portion 110 configured to support the rib 310, a cylindrical guide portion 120 provided at the center of the supporting portion 110, And an elastic member 130 provided within the housing 120. Here, the top plate of the driving unit 100 is removed for ease of explanation. The upper plate of the driving part 100 may be provided at a position facing the support part 110 so as to cover the predetermined part of the rib 310 and the guide part 120. [

The supporting portion 110 is supported by abutting against the rib 310 and is configured to continuously support a plurality of ribs 310 when the plurality of ribs 310 rotate when the antenna reflector 300 is deployed .

To this end, the support 110 may include a base plate 111, a lift plate 113, and a height adjusting member 115.

The base plate 111 may have a disc shape. The base plate 111 can be engaged with the guide portion 120 at its central portion. The base plate 111 may have a separate groove. A height adjusting member 115 may be provided in the groove of the base plate 111.

The height adjusting member 115 may be a kind of coil spring. The height adjusting member 115 may be provided while retaining elastic energy in a compressed state. The height adjusting member 115 may be provided between the base plate 111 and the lift plate 113. The height adjusting member 115 can push up the rising plate 113 using elastic energy.

The lift plate 113 may be provided to cover the upper surface of the base plate 111. The rising plate 113 may have an inner hollow shape. The lifting plate 113 can be held in close contact with the rib 310 by the height adjusting member 115. [ When the plurality of ribs 310 are rotated along the outer periphery of the guide portion 120, the lift plate 113 is lifted by the height adjustment member 115 and continues to abut on the ribs 310. When the antenna reflector 300 is completely deployed, the lift plate 113 abuts and supports the entire plurality of ribs 310.

The guide part 120 may be provided at the center of the base plate 111 of the support part 110. The guide portion 120 may have a cylindrical shape. The guide part 120 may include an outer cylindrical part 121 and an inner cylindrical part 123.

The slits s and the guide holes h may be formed in the outer cylindrical portion 121 so that the ribs 310 are penetrated.

The slits s and the guide holes h of the outer cylindrical portion 121 may be alternately formed at predetermined intervals along the outer circumference of the outer cylindrical portion 121. The slits s of the outer cylindrical portion 121 and the guide holes h may be formed at different heights. That is, the slits s and the guide holes h of the outer cylindrical portion 121 are formed so as to follow the counterclockwise direction (refer to FIG. 3) of the outer cylindrical portion 121 with reference to the positions of the ribs 310 in the stacked state It is preferable to be formed at a relatively high position.

Each of the slits s of the outer cylindrical portion 121 can communicate with each other by a plurality of guide holes h. The rib 310 at the lowermost end is rotatable along the slit s and the guide hole h of the outer cylindrical portion 121.

The first protrusion 311 may be extended to the uppermost rib 310 and the second protrusion 313 may be extended to the lowermost rib 310. The first protrusion 311 may be positioned through the guide hole h of the outer cylindrical portion 121. So that the first projection 311 can fix the uppermost rib 310 to the outer cylindrical portion 121.

The second projection 313 may be positioned through the slit s of the outer cylindrical portion 121. The second projection 313 can move along the slit s of the outer cylindrical portion 121. [ When the second projection 313 reaches the guide hole h, the second projection 313 rises to the upper portion of the guide hole h by the lift plate 113 and is movable along the slit s. So that the second protrusion 313 can rotate the lowermost rib 310 along the outer circumference of the outer cylindrical portion 121.

The inner cylindrical portion 123 may be provided inside the outer cylindrical portion 121. The inner cylindrical portion 123 may have a fixing block 123a formed on the outer circumference thereof. The fixing block 123a may be provided at a position facing the uppermost rib 310. [ The fixed block 123a may have an empty space formed therein. A spring sp may be provided inside the fixed block 123a. The fixed block 123a may be formed with a slit extending in the vertical direction. One end of the elastic member 130 may be connected to the upper portion of the spring sp in the fixing block 123a through the slit of the fixing block 123a.

The elastic member 130 may be provided between the outer cylindrical portion 121 and the inner cylindrical portion 123. One end of the elastic member 130 may be connected to the spring sp of the inner cylindrical portion 123 and the other end may be connected to the second projection 313 of the rib 310 at the lowermost end. The elastic member 130 may be a kind of torsion spring. The elastic member 130 may be connected to the second protrusion 313 of the lowermost rib 310 while retaining elastic energy when the antenna reflector 300 is not deployed. Here, the elastic member 130 may be provided in a state of retaining elastic energy by a separate lock member (not shown). The elastic member 130 can rotate the rib 310 using elastic energy when the current state is changed to the unlocked state by the separate lock member. Thus, the rib 310 is rotatable by the elastic member 130 of the driving unit 100, which is a mechanical driving element, not an electrical driving element. On the other hand, the elastic member 130 may be replaced with an electric driving element composed of a motor and a bearing combination as required.

Referring again to FIGS. 1 and 2, the feeder 200 may be provided on the central axis of the driving unit 100. For this, a tripod 500 may be provided. The feeder 200 is provided for transmitting and receiving communication information with the satellite terminal.

The antenna reflector 300 is provided to reflect the radio waves of the receiver satellite terminal and transmit the reflected waves to the feeder 200 and may include a plurality of ribs 310 and a plurality of reflection sheets 320.

The plurality of ribs 310 may be provided for reinforcing the rigidity of the reflective sheet 320. The plurality of ribs 310 may be radially arranged around the feeder 200 when the antenna reflector 300 is deployed. The plurality of ribs 310 may be stacked on each other when the antenna reflector 300 is not deployed. To this end, a plurality of ribs 310 may be rotatably connected to the driving unit 100. Here, the connection structure between the plurality of ribs 310 and the driving unit 100 has been described above, and a description thereof will be omitted.

The plurality of ribs 310 may be composed of a spring steel or a shape memory alloy material at the bottom. So that the plurality of ribs 310 can be folded so as to converge toward the feeder 200. This helps to reduce the size of the satellite when the antenna 10 is mounted on the satellite.

The plurality of ribs 310 can be folded while preserving the elastic energy so that the ribs 310 can be spread away from the feeder 200 when the antenna reflector 300 is deployed. The plurality of ribs 310 may be made of a composite material for weight saving, except for a portion made of spring steel or a shape memory alloy material. Here, the composite material may include Glass Fiber Reinforced Plastic (GFRP) and Carbon Fiber Reinforced Plastic (CFRP). The composite material to be applied to the plurality of ribs 310 may be a woven type composite material having the same physical properties in the 0 ° to 90 ° direction for bidirectional rigidity preservation. Since the composite material is an anisotropic material having a strong strength at a specific incense, the strength can be sufficiently secured by laminating the composite material at different lamination angles.

Further, the plurality of ribs 310 can be manufactured through autoclave processing using a mold so that the ribs 310 can be formed with high accuracy. The fabrication of such a plurality of ribs 310 will be described with reference to FIG.

First, at the mold stage, prepare a mold to be used for production, remove the foreign substance, and clean it. Then, in the raw material cutting stage, the raw material is discharged from the freezer to perform cutting work. Then, in the stacking step, the raw materials are stacked according to the stacking information, and a sealing operation is performed for each designated ply. Then, in the forming and sealing step, a final sealing operation is performed before molding. Then, in the A / C molding step, A / C molding is performed according to the designated cycle. Then, in the demoulding step, be careful not to damage the product and remove it from the mold. Then, in the machining step, E.O.P. and hole machining are performed in consideration of the shape tolerance. Finally, in the final inspection step, final dimension inspection is carried out in accordance with the drawings. The plurality of ribs 310 fabricated in this way are lightweight and can secure sufficient strength.

Referring again to FIGS. 1 and 2, a plurality of reflective sheets 320 may be provided between the plurality of ribs 310. Both sides of the plurality of reflective sheets 320 can be connected to the side surfaces of the ribs 310. The plurality of reflective sheets 320 may be provided with fold lines in the longitudinal direction at the center. The plurality of reflection sheets 320 may be unfolded upon deployment of the antenna reflector 300 and arranged radially about the feeder 200. The plurality of reflective sheets 320 can be held in a folded state about the fold line when the antenna reflector 300 is not deployed. To this end, the plurality of reflective sheets 320 may be formed of a mesh or a membrane material. Thus, the plurality of reflective sheets 320 can be designed to be lightweight and can satisfy the weight limitation requirements of the satellite launch vehicle.

The rib 310 of the antenna reflector 300 may be fixed to the feeder 200 by the fixing device 400 so that the rib 310 of the antenna reflector 300 is folded toward the feeder 200 while being folded.

5 and 6, the fixing device 400 connects the antenna reflector 300 to the feeder 200 and fixes the feeder 200 so that the feeder 200 is held in a folded state. The fixing device 400 includes an electromagnet 410, 420, and a damper member 430, as shown in FIG.

The electromagnet 410 may be provided in the feeder 200 as having a magnetic property when power is supplied thereto. The electromagnet 410 may be provided along the outer periphery of the feeder 200, but is not limited thereto.

The metal member 420 may be provided on the rib 310 of the antenna reflector 300. The metal member 420 may have a long rod shape. One end of the metal member 420 may be connected to the uppermost rib 310 and the other end may be connected to the feeder 200 through engagement with the electromagnet 410.

The damper member 430 may be formed to connect the feeder 200 and the rib 310 and to surround the metal member 430. The damper member 430 may be made of an elastic material that can be stretched or shrunk. The damper member 430 may be a coil spring.

6 (a), the metal member 420 is in a state of being magnetically coupled to the electromagnet 410. At this time, electric current is supplied to the electromagnet 410, so that the electromagnet 410 has a magnetic property. The current flowing through the electromagnet 410 is transmitted through a separate cable. Here, the cable may be provided inside the tripod 500. That is, the tripod 500 is preferably formed by a hollow top so that a cable can be provided inside.

In Fig. 6B, the metal member 420 is in a state in which the electromagnet 410 is disengaged from the magnet. At this time, current supply to the electromagnet 410 is stopped. The damper member 430 is elongated as the metal member 420 is separated from the electromagnet 410.

Hereinafter, the development process of the antenna reflector 300 will be described with reference to FIGS. 7 to 10. FIG.

First, in FIG. 7, when the satellite reaches the space orbit and the antenna reflector 300 of the antenna 10 starts to be deployed, the power supply to the fixing device 400 is stopped. At this time, the antenna reflector 300 fixed to the feeder 200 by the fixing device 400 spreads away from the feeder 200. This is possible by the elastic energy of the rib 310 of the antenna reflector 300. The fixing device 400 prevents sudden expansion of the antenna reflector 300 through the elastic energy of the damper member 430.

8, when the rib 310 is completely separated from the feeder 200, the rib 310 of the lowermost stage rotates along the outer periphery of the driving part 100, (310) sequentially rotate. The rotation of the rib 310 will be described with reference to FIGS. 9 and 10. FIG.

9, the rib 310 at the lowermost end rotates along the outer periphery of the outer cylindrical portion 121 by the elastic energy of the elastic member 130. Here, the elastic member 130 normally retains elastic energy by a separate locking member. When the lock member is unlocked by the antenna expansion signal, the elastic member 130 is contracted along the outer periphery of the inner cylindrical portion 123, thereby rotating the rib 310 at the lowermost end. At this time, the reflective sheet 120 connected to the lowermost rib 310 is unfolded. Meanwhile, a ball plunger (BP) may be provided on the bottom surface of each of the plurality of ribs 310. This facilitates rotation of the plurality of ribs 310.

When the rib 310 at the lowermost end is located in the guide hole h (see FIG. 4) described above, it is raised by the lift plate 113. At this time, the lowermost rib 310 and the upper rib 310 connected to the lowermost rib 310 are held in contact with the rising plate 113.

10, the lowermost rib 310 alternately passes through the slit s of the outer cylindrical portion 121 and the guide hole h, and finally reaches the same height as the uppermost rib 310. When the bottom end of the rib 310 is completely rotated and positioned at the same height as the uppermost rib 310, the entire rib 310 is abutted against the lifting plate 113. Here, the elastic member 130 is lifted together with the rib 310 by the spring SP. At this time, the reflection sheet 320 is completely unfolded and arranged in a radial pattern around the feeder 200 (see FIG. 1). Then, the antenna reflector 300 performs its function.

Accordingly, the artificial satellite antenna 10 according to the embodiment of the present invention can contribute to the reduction of the size of the artificial satellite by improving the structure and the development method as described above, and the risk of failure in the space environment can be reduced.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is evident that many alternatives, modifications and variations will be apparent to those skilled in the art.

Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

10: Antenna for satellite
100:
110: Support
111: base plate
113: lift plate
115: height adjustment member
120: guide portion
121:
h: Guide hole
s: slit
123: Inner cylinder portion
123a: fixed block
130: elastic member
200: feeder
300: antenna reflector
310: rib
BP: Ball plunger
311: first protrusion
313: second projection
320: reflective sheet
400: Fixing device
410: electromagnet
420: metal member
430: damper member
500: Tripod

Claims (13)

A driving unit;
A feeder provided on a central axis of the driving unit; And
An antenna reflector comprising a plurality of ribs rotatably connected to the driving unit, and a plurality of reflective sheets provided between the plurality of ribs;
/ RTI >
Wherein the driving unit includes a disk-shaped support portion configured to support the rib, a cylindrical guide portion provided at the center of the support portion, and an elastic member provided inside the guide portion,
The ribs being connected to the elastic member through the guide portion,
Wherein when the antenna reflector is unfolded, the plurality of ribs are stacked, the reflective sheet is held in a folded state,
Wherein when the antenna reflector is deployed, the rib is rotated along the outer periphery of the guide portion by the elastic member, and the reflection sheet is unfolded and arranged in a radial fashion about the feeder. delete The method according to claim 1,
The guide portion
An outer cylindrical portion having a slit through which the rib is inserted; And
An inner cylindrical portion provided inside the outer cylindrical portion;
Lt; / RTI >
Wherein the elastic member is provided between the outer cylindrical portion and the inner cylindrical portion. The method of claim 3,
Wherein the elastic member is a torsion spring having one end connected to the inner cylindrical portion and the other end connected to the rib. The method of claim 3,
Wherein the outer cylindrical portion has a plurality of guide holes and a plurality of slits alternately arranged at predetermined intervals along the outer periphery and formed at different heights,
And the guide hole and the slit communicate with each other. 6. The method of claim 5,
Wherein the rib moves along the slit and the guide hole by elastic energy of the elastic member. The method according to claim 1,
The support portion
A base plate coupled to the guide portion;
A lift plate which abuts the ribs; And
A height adjusting member provided between the base plate and the rising plate;
And an antenna for a satellite. 8. The method of claim 7,
Wherein the height adjusting member is a coil spring. The method according to claim 1,
And a fixing device for connecting the feeder and the rib. 10. The method of claim 9,
The fixing device includes:
An electromagnet provided in the feeder; And
A metal member provided on the rib and capable of magnet coupling with the electromagnet;
A damper member connecting the feeder and the rib to surround the metal member;
And an antenna for a satellite. 11. The method of claim 10,
The ribs
Wherein when the metal member is magnetically coupled to the electromagnet, the metal member is folded toward the feeder while being folded, and when the metal member is disengaged from the electromagnet, the antenna is extended away from the feeder. 12. The method of claim 11,
Wherein the rib is made of spring steel or a shape memory alloy material. The method according to claim 1,
And a ball plunger is formed on one side of each of the ribs.

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