Transmission line transition

A transmission line transition for coupling electromagnetic energy comprising:

• a first dielectric substrate having a first portion;
• a waveguide tube including a hollow interior that has a longitudinal direction and a first cross-sectional area perpendicular to the longitudinal direction, one open end of the waveguide tube being attached to a first surface of the first dielectric substrate;
• a second dielectric substrate disposed on a second surface of the first dielectric substrate and having a second portion, the second portion and the first portion of the first dielectric substrate providing a dielectric waveguide having a first end short-circuited and a second end communicating with the hollow interior of the waveguide tube;
• a planar line disposed on one of the first and second dielectric substrates;
• and
• an antenna electrically connected to the planar line and disposed in the dielectric waveguide to excite and to be excited by the waveguide tube, the antenna being spaced from the short-circuited end of the dielectric waveguide by a predetermined distance in the longitudinal direction, wherein
• the electromagnetic energy is coupled between the waveguide tube, the dielectric waveguide, and the planar line.