MEMS based RF components and a method of construction thereof

• US 20060176124A1
• Filed: 02/10/2005
• Published: 08/10/2006
• Est. Priority Date: 02/10/2005
• Status: Abandoned Application

• Current Assignee: Mojgan Daneshmand, Raafat R. Mansour
• Original Assignee: Mojgan Daneshmand, Raafat R. Mansour
• Inventors: Mansour, Raafat R., Daneshmand, Mojgan
• Application Number:
  US11/053,871
• Publication Number:
  US 20060176124A1
• Time in Patent Office: Days
• US Class Current: 333/108
• CPC Class Codes: H01P 1/122 Waveguide switches
• CPC Class Codes: H01P 1/125 Coaxial switches

Abstract

A three dimensional waveguide is integrated with a MEMS structure to control a signal in various RF components. The components include switches, variable capacitors, filters and phase shifters. A controller controls movement of the MEMS structure to control a signal within the component. A method of construction and a method of operation of the component are described. The switches have high power handling capability and can be operated at high frequencies. By integrating a three dimensional waveguide with a MEMS structure, the components can be small in size with good operating characteristics.

Claims

1. A MEMS-based RF component comprising a form, said form being a three dimensional waveguide, said form being capable of supporting a signal and having at least one of an input and output, said form having a MEMS structure at least partially therein, said MEMS structure being constructed to control an RF signal within said form.

2. A component as claimed in claim 1 wherein said MEMS structure has a first position and a second position.

3. A component as claimed in claim 2 wherein there is a controller to control movement of said MEMS structure

4. A component as claimed in claim 3 wherein said MEMS structure has a plurality of actuators, said actuators being movable between said first position and said second position.

5. A component as claimed in claim 3 wherein said MEMS structure is located in said waveguide.

6. A component as claimed in claim 3 wherein said MEMS structure is integrated with said waveguide.

7. A component as claimed in claim 3 wherein said waveguide is at least one of a rectangular waveguide, a coaxial waveguide, a ridge waveguide, a single ridge waveguide and a double ridge waveguide.

8. A component as claimed in claim 7 wherein the component is one selected from the group of a switch, capacitor, variable capacitor, phase shifter and filter.

9. A component as claimed in claim 3 wherein said component is a switch, said form has a signal path and said MEMS structure is located out of said path in said first position and at least partially within said path in said second position.

10. A component as claimed in claim 9 wherein said switch is on in said first position and off in said second position.

11. A component as claimed in claim 8 wherein said component is a switch selected from the group of an R-switch, C-switch, a T-switch, single pole single throw switch, single pole double throw switch, switch matrix and coaxial switch, planar switch and waveguide switch integrated with a planar circuit.

12. A component as claimed in claim 4 wherein said actuators are at least one selected from the group of thermal, magnetic, electrostatic, curling actuators and plastic deformation type of actuators.

13. A component as claimed in claim 6 wherein said component is a C-switch with two input ports and two output ports of said at least one of an input and an output.

14. A component as claimed in claim 6 wherein said switch is a T-switch with two input ports and two output ports of said at least one of an input and output.

15. A component as claimed in claim 6 wherein said component is an R-switch with a maximum of two input ports and two output ports of said at least one of an input and output in any single position of said switch.

16. A component as claimed in claim 6 wherein said component is a coaxial switch with at least one input and at least one output of said at least one input and output.

17. A component as claimed in claim 6 wherein said component is a single pole double throw switch having one input and two outputs of said at least one input and output.

18. A component as claimed in claim 3 wherein said component has a ridge waveguide channel therein with a gap located above a bottom plate, said MEMS structure being located beneath said gap.

19. A component as claimed in claim 18 wherein said component has a top that is sized and shaped to fit onto said bottom plate, said ridge waveguide being located in said top.

20. A component as claimed in claim 3 wherein said component has at least one input port and at least one output port of said at least one input and output, said ports having transformers located therein.

21. A component as claimed in claim 4 wherein said actuators are constructed to short circuit said signal path to turn said switch off.

22. A component as claimed in claim 10 wherein said component has more than one signal path with a MEMS structure located at each signal path, said MEMS structure having actuators that are constructed to short circuit a signal path in which the actuators are located when said signal path is off.

23. A component as claimed in claim 22 wherein said actuators are constructed to be located outside of a signal path when said signal path is on.

24. A component as claimed in claim 19 wherein said top has gold plating thereon.

25. A component as claimed in claim 4 wherein said actuators are movable up and down in a switch to provide a short between a top and bottom plate when said switch is off and to be removed entirely to a position coinciding with an inner wall of a waveguide when said switch is on, said actuators having a capacitive loading.

26. A component as claimed in claim 4 wherein said actuators are controlled to adjust an elevation of said actuators resulting an a controllable capacitative loading of said waveguide.

27. A component as claimed in claim 4 wherein said actuators are located and constructed to provide a variable inline capacitor.

28. A component as claimed in claim 27 wherein the variable inline capacitor is located in one of a phase shifter, tunable filter, matching network and any reconfigurable system.

29. A component as claimed in claim 1 wherein said component is constructed for use in a waveband selected from the group of microwave, millimeter, terahertz and beyond.

30. A component as claimed in claim 4 wherein the component is a switch matrix comprised of a plurality of switches that are interconnected to one another, said switch matrix having a plurality of inputs and a plurality of outputs of said at least one input and output, the plurality of switches in said switch matrix having a MEMS structure with a plurality of actuators that are movable between a first position and a second position.

31. A component as claimed in claim 3 wherein said component has a configuration that is selected from the group of a planar configuration, a coplanar-waveguide configuration and low temperature cofired ceramic configuration.

32. A component as claimed in claim 1 wherein the MEMS structure is integrated on a planar circuit.

33. A component as claimed in claim 1 wherein the component is a wide-band ridge waveguide connected into a coplanar waveguide line transition.

34. A component as claimed in claim 33 wherein said MEMS structure is integrated onto a bottom plate and a waveguide channel and ridge are fabricated on a top cover.

35. A component as claimed in claim 34 wherein a microstrip line is used as an interface to transform a ridge waveguide mode to a coplanar waveguide mode.

36. A method of constructing a MEMS-based RF component having a three dimensional waveguide with a MEMS structure at least partially therein, said method comprising constructing a base plate and a top cover that is sized and shaped to fit on said base plate, one of said base plate and said top cover having a MEMS structure incorporated therein, and affixing said cover to said plate to form said component.

37. A method as claimed in claim 36 including the step of incorporating the MEMS structure in said base plate and incorporating a waveguide in said cover.

38. A method as claim in claim 37 including the step of incorporating a ridge waveguide in said cover.

39. A method as claimed in claim 37 including the step of fabricating the MEMS structure, the cover and the base plate by the same process monolithically.

40. A method as claimed in claim 36 including the steps of constructing the MEMS structure separately from said cover.

41. A method of operating an RF component having a form that is a three dimensional waveguide, said form having a MEMS structure at least partially therein with a controller for said MEMS structure, said method comprising operating said controller to move said MEMS structure to control an RF signal within said form.