Inductive coupling in transverse electromagnetic mode

1. A circuit comprising:

a first and a second electromagnetic resonator, each configured to operate in a transverse electromagnetic mode, the first electromagnetic resonator being operable at a first resonant frequency and the second electromagnetic resonator being operable at a second resonant frequency; and

a coupling device configured to operate in the transverse electromagnetic mode,

wherein the coupling device is directly connected to the first electromagnetic resonator at a first connection point and directly connected to the second electromagnetic resonator at a second connection point, and the coupling device inductively couples the first and second electromagnetic resonators and provides a coupling value of at least 0.12,

wherein the coupling device is entirely electrically conductive, and wherein each of the first and second connection points is at a non-zero potential.

2. The circuit of claim 1 , wherein the first and second resonators are planar folded-line resonators and are interleaved.

3. The circuit of claim 1 , wherein the first resonator is a cavity resonator.

4. The circuit of claim 1 , wherein the first resonator is a planar resonator.

5. The circuit of claim 1 , wherein the coupling device is inserted through an opening in a wall shared by the first and second electromagnetic resonators.

6. The circuit of claim 1 , wherein the first electromagnetic resonator is a single-mode resonator.

7. The circuit of claim 1 , wherein the first electromagnetic resonator is a multi-mode resonator.

8. The circuit of claim 1 , wherein the first electromagnetic resonator and the second electromagnetic resonator are one of a combline configuration, a folded-line configuration, and an interdigital configuration.

9. The circuit of claim 1 , wherein the first electromagnetic resonator operates in a different mode than the second electromagnetic resonator.

10. The circuit of claim 1 , wherein a configuration of the first electromagnetic resonator is different from a configuration of the second electromagnetic resonator.

11. The circuit of claim 1 , wherein the coupling device is configured to convey a signal from the first resonator to the second resonator.

12. The circuit of claim 11 , wherein the coupling device is configured to convey the signal across a magnetic field.

13. The circuit of claim 12 , wherein the magnetic field is dominant in strength relative to an electric field.

14. The circuit of claim 1 , wherein the coupling device includes a conductive transmission line.

15. The circuit of claim 1 , wherein the coupling device includes a metallic material.

16. The circuit of claim 1 , wherein the coupling device includes a strip.

17. The circuit of claim 16 , wherein the geometry of the strip includes one of a straight shape, meandering shape, a fractal shape, and a spiral shape.

18. The circuit of claim 1 , wherein the coupling device includes a bar.

19. The circuit of claim 1 , wherein the coupling device includes a rod.

20. The circuit of claim 1 , wherein the coupling device includes a cylindrical structure.

21. The circuit of claim 1 , wherein the first electromagnetic resonator is configured to operate in a range of radio frequencies.

22. The circuit of claim 1 , wherein the first electromagnetic resonator is configured to operate in the range of microwave frequencies.

23. The circuit of claim 1 , wherein the first and second electromagnetic resonators are synchronously tuned.

24. The circuit of claim 1 , wherein the first and second electromagnetic resonators are asynchronously tuned.

25. The circuit of claim 1 , wherein the first resonator is tuned in at least one of an electrical, mechanical, or magnetic manner.

26. The circuit of claim 1 , wherein the first and second resonators form a portion of an active component.

27. The circuit of claim 1 , wherein the first and second resonators form a portion of a passive component.

28. The circuit of claim 1 , wherein the first and second resonators form a portion of a symmetric component.

29. The circuit of claim 1 , wherein the first and second resonators form a portion of an asymmetric component.

30. The circuit of claim 1 , wherein the first electromagnetic resonator and the coupling device are formed in a substrate.

31. The circuit of claim 1 , wherein the first electromagnetic resonator, the second electromagnetic resonator and the coupling device are formed in a substrate.

32. The circuit of claim 1 , wherein the first electromagnetic resonator has a length of less than one quarter of its resonant frequency wavelength.

33. The circuit of claim 1 , wherein the coupling device has a dimension of at least 1 millimeter.

34. The circuit of claim 1 , wherein the coupling device is representable as an inductance having a nano-henry (nH) value.

35. The circuit of claim 1 , wherein the first and second resonators are slow-mode resonators comprising fractal resonators, circular-ring resonators, rectangular-ring resonators, or split-ring resonators.

36. The circuit of claim 1 , wherein the first resonator or the second resonator has a length that is a fraction of a wavelength at the first resonant frequency or the second resonant frequency of the first or second resonator.

37. The circuit of claim 1 , wherein the first resonator or the second resonator has a length that is times of a wavelength at the first resonant frequency or the second resonant frequency of the first or second resonator.

38. An apparatus comprising:

a planar frequency filter formed in a dielectric substrate, and having a first and a second planar resonator, each configured to operate in a transverse electromagnetic mode, the first planar resonator being operable at a first resonant frequency and the second planar resonator being operable at a second resonant frequency;

at least one feed line connected to the first planar resonator and being capable of providing a signal to the first planar resonator; and

an inductive planar coupling strip directly connected to the first and second planar resonators, wherein the inductive planar coupling strip is configured to operate in a transverse electromagnetic mode and is capable of conveying portions of the signal from the first planar resonator to the second planar resonator, wherein the inductive planar coupling strip is connected to the first planar resonator at a first connection point and the second planar at a second connection point, and the inductive planar coupling strip inductively couples the first and second planar resonators and provides a coupling value of at least 0.12, wherein the inductive planar coupling strip is entirely electrically conductive, and wherein each of the first and second connection points is at a non-zero potential.

39. The apparatus of claim 38 , wherein the inductive planar coupling strip is configured to convey the signal across a magnetic field.

40. The apparatus of claim 38 , wherein the first planar resonator has a length of less than one quarter of its resonant frequency.

41. The apparatus of claim 38 , wherein the inductive planar coupling strip has a dimension of at least 1 millimeter.

42. The apparatus of claim 38 , wherein the inductive planar coupling strip is representable as an inductance having a nano-henry (nH) value.

43. An apparatus comprising:

an inductive coupling device configured to operate in a transverse electromagnetic mode and configured to directly connect at least two resonators, the two resonators being operable at a first resonant frequency and a second resonant frequency, respectively; and

wherein the inductive coupling device is connected to a first resonator of the two resonators at a first connection point and to a second resonator of the two resonators at a second connection point, and the inductive coupling device inductively couples the first and second resonators and provides a coupling value of at least 0.12, wherein the inductive coupling device is entirely electrically conductive, and wherein each of the first and second connection points is at a non-zero potential.

44. The apparatus of claim 43 , wherein each resonator is configured to operate in a transverse electromagnetic mode.

45. The apparatus of claim 43 , wherein each resonator is configured to operate in a transverse electric mode.

46. The apparatus of claim 43 , wherein the coupling device is configured to convey a signal across a magnetic field.

47. The apparatus of claim 43 , wherein at least one of the two resonators has a length of less than one quarter of its resonant frequency wavelength.

48. The apparatus of claim 43 , wherein the inductive coupling device has a dimension of at least 1 millimeter.

49. The apparatus of claim 43 , wherein the inductive coupling device is representable as an inductance having a nano-henry (nH) value.