Switchable microwave fluidic polarizer

• US 8,487,823 B2
• Filed: 11/12/2009
• Issued: 07/16/2013
• Est. Priority Date: 11/12/2009
• Status: Active Grant

• Current Assignee: Raytheon Company (Rtx Corporation)
• Original Assignee: Raytheon Company (Rtx Corporation)
• Inventors: Quan, Clifton, Hauhe, Mark
• Primary Examiner(s): Karacsony, Robert
• Application Number:
  US12/617,509
• Publication Number:
  US 20110109519A1
• Time in Patent Office: 1,342 Days
• Field of Search: 343/756, 343/909
• US Class Current: 343/756
• CPC Class Codes: H01Q 1/422 comprising two or more layers of dielectric material H01Q1/425 takes precedence
• CPC Class Codes: H01Q 15/0006 Devices acting selectively as reflecting surface, as diffracting or as refracting device, e.g. frequency filtering or angular spatial filtering devices H01Q15/12, H01Q15/22, H01Q15/24 take precedence
• CPC Class Codes: H01Q 15/244 converting a linear polarised wave into a circular polarised wave guided wave H01P1/17
• CPC Class Codes: H01Q 21/061 Two dimensional planar arrays

Abstract

A switchable microwave fluidic polarizer is provided. In one embodiment, the invention relates to a switchable polarizer for polarizing radio frequency (RF) signals associated with an antenna, the switchable polarizer including a plurality of radiating elements, an RF feed coupled to the plurality of radiating elements, an antenna input coupled to the RF feed, and an antenna cover disposed in proximity to the plurality of radiating elements, the antenna cover including a dielectric substrate including a plurality of channels for enclosing a liquid metal.

Claims

1. A switchable polarizer for polarizing radio frequency (RF) signals associated with an antenna, the switchable polarizer comprising:

a plurality of radiating elements;

an RF feed coupled to the plurality of radiating elements;

an antenna input coupled to the RF feed; and

an antenna cover disposed in proximity to the plurality of radiating elements, the antenna cover comprising;

a dielectric substrate comprising a plurality of channels for enclosing a liquid metal;

wherein, in a first state, the switchable polarizer is configured to allow incident signals to pass without affecting a polarization of the incident signals;

wherein, in a second state, the switchable polarizer is configured to change the polarization of the incident signals from a linear polarization to a circular polarization;

wherein the plurality of channels are substantially empty of the liquid metal in the first state; and

wherein the plurality of channels are substantially filled with the liquid metal in the second state.

2. The switchable polarizer of claim 1, wherein the dielectric substrate comprises:

a first dielectric sheet comprising the channels; and

a second dielectric sheet fused to the first dielectric sheet to enclose the plurality of channels.

3. The switchable polarizer of claim 2, wherein the plurality of channels comprise an array of channels disposed within the dielectric substrate.

4. The switchable polarizer of claim 3, wherein the array of channels comprise a plurality of meander-line channels.

5. The switchable polarizer of claim 1, further comprising:

a pump coupled to at least one of the plurality of channels, the pump configured to move the liquid metal into, and out of, the at least one of the plurality of channels.

6. The switchable polarizer of claim 5, wherein the pump is coupled to each of the plurality of channels.

7. The switchable polarizer of claim 1, further comprising:

a first pump coupled to at least one of the plurality of channels, the first pump configured to move the liquid metal into the at least one channel; and

a second pump coupled to the at least one channel, the second pump configured to move the liquid metal out of the at least one channel.

8. The switchable polarizer of claim 7, wherein the second pump is configured to pump an air dielectric into the at least one channel.

9. The switchable polarizer of claim 7, wherein the second pump is configured to pump a liquid dielectric into the at least one channel.

10. The switchable polarizer of claim 9, further comprising a movable piston disposed within the at least one channel and between the liquid metal and the liquid dielectric.

11. The switchable polarizer of claim 1, wherein the dielectric substrate comprises a flat rectangular sheet.

12. The switchable polarizer of claim 1, wherein the dielectric substrate comprises at least one curved surface.

13. The switchable polarizer of claim 1, wherein the plurality of channels comprise a plurality of meander-line channels.

14. The switchable polarizer of claim 13, wherein at least one of the plurality of meander-line channels has a repeating S-shape.

15. A process for operating a switchable polarizer comprising an antenna cover disposed in proximity to a plurality of radiating elements, the antenna cover comprising a dielectric substrate having a plurality of channels for enclosing a liquid metal, the process comprising:

filling the plurality of channels with a liquid metal, in a first state, to change a polarization of signals incident to the switchable polarizer from a linear polarization to a circular polarization; and

removing the liquid metal from the plurality of channels, in a second state, to allow signals incident to the switchable polarizer to pass without affecting the polarization of the incident signals.

16. The process for operating the switchable polarizer of claim 15, wherein the dielectric substrate comprises:

a first dielectric sheet comprising the plurality of channels; and

a second dielectric sheet fused to the first dielectric sheet to enclose the plurality of channels.

17. The process for operating the switchable polarizer of claim 16, wherein the plurality of channels comprise an array of meander-line channels disposed within the dielectric substrate.

18. The process for operating the switchable polarizer of claim 15, further comprising:

a pump coupled to at least one of the plurality of channels, the pump configured to move the liquid metal into, and out of, the at least one of the plurality of channels.

19. The process for operating the switchable polarizer of claim 18, wherein the pump is coupled to each of the plurality of channels.

20. The process for operating the switchable polarizer of claim 15, further comprising:

a first pump coupled to at least one of the plurality of channels, the first pump configured to move the liquid metal into the at least one channel; and

a second pump coupled to the at least one channel, the second pump configured to move the liquid metal out of the at least one channel.

21. The process for operating the switchable polarizer of claim 20, wherein the second pump is configured to pump an air dielectric into the at least one channel.

22. The process for operating the switchable polarizer of claim 20, wherein the second pump is configured to pump a liquid dielectric into the at least one channel.

23. The process for operating the switchable polarizer of claim 22, further comprising a movable piston disposed within the at least one channel and between the liquid metal and the liquid dielectric.

24. The process for operating the switchable polarizer of claim 15, wherein the dielectric substrate comprises a flat rectangular sheet.

25. The process for operating the switchable polarizer of claim 15, wherein the dielectric substrate comprises at least one curved surface.

26. The process for operating the switchable polarizer of claim 15, wherein the plurality of channels comprise a plurality of meander-line channels.

27. The process for operating the switchable polarizer of claim 26, wherein at least one of the plurality of meander-line channels has a repeating S-shape.

28. A switchable polarizer for polarizing radio frequency (RF) signals associated with an antenna, the switchable polarizer comprising:

a plurality of radiating elements;

an RF feed coupled to the plurality of radiating elements;

an antenna input coupled to the RF feed; and

an antenna cover disposed in proximity to the plurality of radiating elements, the antenna cover comprising;

a dielectric substrate comprising a plurality of meander-line channels configured to enclose a liquid metal,

wherein the switchable polarizer is configured to switch between a first state and a second state;

wherein the plurality of channels are substantially empty of the liquid metal in the first state;

wherein the plurality of channels are substantially filled with the liquid metal in the second state; and

wherein, in the second state, the switchable polarizer is configured to change a polarization of incident signals.

29. A switchable polarizer for polarizing radio frequency (RF) signals associated with an antenna, the switchable polarizer comprising:

a plurality of radiating elements;

an RF feed coupled to the plurality of radiating elements;

an antenna input coupled to the RF feed; and

an antenna cover disposed in proximity to the plurality of radiating elements, the antenna cover comprising;

a dielectric substrate comprising a plurality of meander-line channels configured to enclose a liquid metal,

wherein the switchable polarizer is configured to switch between a first state and a second state;

wherein the plurality of channels are substantially empty of the liquid metal in the first state;

wherein the plurality of channels are substantially filled with the liquid metal in the second state; and

wherein, in the second state, the switchable polarizer is configured to change a polarization of incident signals from a linear polarization to a circular polarization.