Waveguide coupler with self-contained polarization rotation for integrated waveguides, circuits, and systems

A module comprising:

• a first port for a first H-plane signal to propagate therethrough;
• a second port for a first E-plane signal to propagate therethrough;
• a third port for a second E-plane signal to propagate therethrough;
• and
• a coupling element for transformation between the first H-plane signal and the first E-plane signal, and for transformation between the first H-plane signal and the second E-plane signal, the coupling element comprising a coupling cavity;
• wherein the first port is located on a first side of the coupling cavity;
• wherein the second port and the third port are located on a second side of the coupling cavity, the second side opposite the first side;
• wherein a third side of the coupling cavity is adjacent the first and second sides as well as proximate to the first and second ports, the third side opposite a fourth side of the coupling cavity;
• wherein a first axis extends perpendicularly between the first and second sides;
• wherein a second axis extends parallel to the third and fourth sides, the second axis orthogonal to the first axis;
• wherein a third axis is orthogonal to the first and second axes;
• wherein the second and third ports are opposite with respect to and symmetrical about a symmetry plane parallel to the first and second axes through a center of the coupling cavity;
• wherein the coupling element comprises:
• a first coupling section comprising a first rectangular-prism cavity forming part of the coupling cavity, the first cavity comprising:
• the first side of the coupling cavity, and
• a first and a second side groove along the fourth side extending parallel to the first axis, the first and second side grooves being symmetrical about the symmetry plane;
• and
• a second coupling section comprising a second rectangular-prism cavity forming part of the coupling cavity, the second cavity comprising:
• the second side of the coupling cavity, and
• two obstructions on corners along the fourth side, the obstructions symmetrical about the symmetry plane.