Matching impedance of a dielectric waveguide to a launching mechanism

1. A waveguide, comprising:

a dielectric core comprising a body portion and a transition region; and

a metallic cladding surrounding the dielectric core;

the body portion of the dielectric core having a first impedance; and

the transition region of the dielectric core having a graduated impedance that gradually changes from the first impedance adjacent the body portion to a second impedance by either a permittivity or a permeability of the transition region varying along a length of the transition region.

2. The waveguide of claim 1 , wherein the impedance of the transition region of the dielectric core gradually changes in two or more discrete sectors, wherein each of the two more discrete sectors each have a different impedance.

3. The waveguide of claim 1 , wherein the impedance of the transition region of the dielectric core gradually changes in a continuous manner.

4. The waveguide of claim 1 , wherein the transition region is located at an end of the waveguide.

5. The waveguide of claim 1 , wherein the transition region has a graduated dielectric constant value that gradually changes from a first dielectric constant value adjacent the body portion to a second dielectric constant value, such that the impedance of the transition region gradually changes.

6. The waveguide of claim 1 , wherein the dielectric core is a graded dielectric core comprising two or more longitudinal regions each having a different dielectric constant value.

7. The waveguide of claim 1 , wherein the dielectric core has a dielectric constant value selected from a range of approximately 2.4-12.

8. The waveguide of claim 1 , further comprising a substrate disposed below a side of the metallic cladding, wherein a surface of the substrate is irregular.

9. The waveguide of claim 1 , wherein the permittivity of the transition region varies.

10. The waveguide of claim 1 , wherein the permeability of the transition region varies.

11. A method of forming a waveguide, the method comprising:

forming a conformal base layer for the waveguide on a surface of a substrate;

forming a body portion having a first dielectric of a dielectric core for the waveguide, on the base layer;

forming a transition region of the dielectric core adjacent the body portion having a graduated impedance that gradually changes from a first impedance adjacent the body portion to a second impedance by either a permittivity or a permeability of the transition region varying along a length of the transition region; and

forming sidewalls and a conformal top layer surrounding the dielectric core and in contact with the base layer;

at least one of the conformal base layer, sidewalls and conformal top layer being metallic.

12. The method of claim 11 , wherein the transition region is formed by gradually changing a dielectric constant from a first dielectric constant value adjacent the body portion to a second dielectric constant value, such that the impedance of the transition region gradually changes.

13. The method of claim 11 , further comprising removing the substrate after forming the waveguide.

14. The method of claim 11 , wherein forming the body portion of the dielectric core comprises forming a graded core region having two or more different dielectric constant values.

15. The method of claim 11 , wherein the conformal base layer is formed to match a footprint of the waveguide.

16. The method of claim 11 , wherein the conformal base layer is formed to extend beyond a footprint of the waveguide.

17. The method of claim 11 , wherein the surface of the substrate is irregular, and wherein the base layer is formed to conform to the irregular surface of the substrate.

18. The method of claim 11 , wherein the permittivity of the transition region varies.

19. The method of claim 11 , wherein the permeability of the transition region varies.

20. The method of claim 11 , wherein forming the transition region of the dielectric core is performed using an ink jet printing process.