INFLATABLE ANTENNA

• US 20140028532A1
• Filed: 07/24/2012
• Published: 01/30/2014
• Est. Priority Date: 07/24/2012
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: EHRENBERG, Robert G., SAMPAT, Sujal
• Granted Patent: US 9,391,373 B2
• Time in Patent Office: Days
• US Class Current: 343/912
• CPC Class Codes: H01Q 1/081 Inflatable antennas
• CPC Class Codes: H01Q 1/1235 Collapsible supports; Means for erecting a rigid antenna
• CPC Class Codes: H01Q 15/163 inflatable
• CPC Class Codes: H01Q 19/19 comprising one main concave reflecting surface associated with an auxiliary reflecting surface
• CPC Class Codes: H01Q 3/08 for varying two co-ordinates of the orientation
• CPC Class Codes: Y10T 29/49016 Antenna or wave energy "plumbing" making

Abstract

An inflatable structure usable as a satellite terminal. An inflatable structure may include an inflatable membrane for forming the structure and two integral RF reflective portions. When the membrane is inflated, the two RF reflective portions oppose each other to form an antenna. One RF reflective portion may be a main reflector and the other RF reflective portion may be a subreflector, both reflectors curvatures that face each other to form a Gregorian antenna or a Cassegrain antenna. In another embodiment, an inflatable antenna may include an inflatable dish including a RF reflective main reflector and an opposing RF transparent dish wall. An inflatable RF transparent support member and an RF reflective subreflector extend from the dish wall. Again, when the antenna is inflated, the main reflector and the subreflector oppose each other to reflect RF energy toward each other to form an antenna.

Claims

1. An inflatable structure, comprising:

an inflatable membrane for forming the structure;

a first radio frequency (RF) reflective portion integral to the inflatable membrane; and

a second RF reflective portion integral to the inflatable membrane;

wherein, when the membrane is inflated, the first RF reflective portion and the second RF reflective portion oppose each other to form an antenna.

2. The inflatable structure of claim 1, wherein the inflatable membrane is made or assembled to be in one piece.

3. The inflatable structure of claim 1, wherein the first RF reflective portion comprises a main reflector and the second RF reflective portion comprises a subreflector.

4. The inflatable structure of claim 3, wherein the main reflector includes a first concave surface and the subreflector includes a second concave surface, and the first concave surface and the second concave surface are spaced from and oppose each other to form a Gregorian antenna.

5. The inflatable structure of claim 3, wherein the main reflector includes a concave surface and the subreflector includes a convex surface, and the concave surface and the convex surface are spaced from and oppose each other to form a Cassegrain antenna.

6. The inflatable structure of claim 3, further comprising transmitting and receiving means and means for attaching the main reflector to the transmitting and receiving means.

7. The inflatable structure of claim 6, wherein the transmitting and receiving means comprises a horn, wherein the inflatable membrane defines an interior volume, the means for attaching the transmitting and receiving means to the main reflector comprises a mounting frame that is attached to the inflatable membrane at the main reflector around the perimeter of the frame and is configured to be releasably secured to the horn, and the mounting frame comprises a valve for a gas or foam source to communicate with the interior volume.

8. The inflatable structure of claim 6, wherein the transmitting and receiving means comprises means for admitting gas or foam to the inflatable membrane.

9. The inflatable structure of claim 1, wherein the entirety of the inflatable membrane is initially RF transparent, and RF reflective material is subsequently added to areas of the inflatable membrane to make such areas be the first RF reflective portion and the second RF reflective portion.

10. The inflatable structure of claim 1, wherein the first RF reflective portion is substantially rectangular in one plane.

11. The inflatable structure of claim 1, wherein the first RF reflective portion is substantially circular in one plane.

12. The inflatable structure of claim 1, wherein the inflatable membrane can be compressed and compacted and subsequently inflated one or more times without substantially altering the original inflated shape of the membrane or the reflective efficiency of the first RF reflective portion and the second RF reflective portion.

13. An inflatable antenna, comprising:

an inflatable dish including a radio frequency (RF) reflective main reflector and an opposing RF transparent dish wall;

an RF transparent support member, extending from the RF transparent dish wall away from the main reflector and having a free end; and

an RF reflective subreflector proximate and attached to the free end of the RF transparent support member, wherein the support member is inflatable and the subreflector is inflatable or maintains its shape when the antenna is not inflated;

wherein, when the antenna is inflated, the main reflector and the subreflector oppose each other to reflect RF energy toward each other to form an antenna.

14. The inflatable antenna of claim 13, wherein the main reflector and the RF transparent dish wall define a dish interior volume, the subreflector and the RF transparent support member define a support member interior volume, and the dish interior volume and the support member interior volume are in fluid communication.

15. The inflatable antenna of claim 13, wherein the main reflector includes an interior surface that is concave and the subreflector includes an interior surface that is concave, and the main reflector interior surface and the subreflector interior surface oppose each other to form a Gregorian antenna.

16. The inflatable antenna of claim 13, wherein the main reflector includes an interior surface that is concave and the subreflector includes an interior surface that is convex, and the main reflector interior surface and the subreflector interior surface oppose each other to form a Cassegrain antenna.

17. The inflatable antenna of claim 13, wherein the main reflector includes an exterior surface, and further comprising transmission and receiving means and attachment means for mounting the main reflector to the transmission and receiving means, and the attachments means comprises a mounting frame with a perimeter, the mounting frame being attached to the main reflector around the perimeter and on the exterior surface of the main reflector.

18. The inflatable antenna of claim 13, wherein the inflatable dish, support member, and subreflector can be compressed and compacted and subsequently inflated one or more times without substantially altering the original inflated shape of the inflatable dish, support member, and subreflector or the reflective efficiency of the main reflector and the subreflector.

19. A method of making an inflatable antenna, comprising:

providing material for forming an inflatable structure;

causing a first portion of the material to be RF reflective;

causing a second portion of the material to be RF reflective; and

assembling the material to form an inflatable membrane;

wherein, when the membrane is inflated, the first portion and the second portion oppose each other to form an antenna.

20. The method of claim 19, wherein, when the membrane is inflated to define an interior volume, the first portion and the second portion form surfaces have curvatures toward the interior volume and to each other to form a Gregorian antenna or a Cassegrain antenna.