Methods and apparatus for adjusting a wavelength electromagnetic waves

A device, comprising:

• a first hollow waveguide coupled to a first dielectric coupler, wherein the first hollow waveguide facilitates coupling, via the first dielectric coupler, a first electromagnetic wave onto a transmission medium;
• a second hollow waveguide coupled to a second dielectric coupler, wherein the second hollow waveguide facilitates coupling, via the second dielectric coupler, a second electromagnetic wave onto the transmission medium, wherein the first electromagnetic wave and the second electromagnetic wave combine to form a combined electromagnetic wave that propagates along the transmission medium without requiring an electrical return path;
• and
• a motor that facilitates adjusting a first length of the first dielectric coupler to adjust a wave mode of the combined electromagnetic wave.

A method, comprising:

• generating, by a first hollow waveguide coupled to a first dielectric coupler, a first electromagnetic wave that couples onto a transmission medium;
• generating, by a second hollow waveguide coupled to a second dielectric coupler, a second electromagnetic wave that couples onto the transmission medium;
• combining the first electromagnetic wave and the second electromagnetic wave to form a combined electromagnetic wave that propagates along the transmission medium without requiring an electrical return path;
• and
• adjusting a first length of the first dielectric coupler to adjust a wave mode of the combined electromagnetic wave.