High isolation dual polarized dipole antenna elements and feed system
View Patent ↗An apparatus that achieves high isolation between dipoles and feed systems is provided. The apparatus includes a plurality of transmission lines, a first dipole electrically connected to a first set of the plurality of transmission lines, and second dipole electrically connected to a second set of the plurality of transmission lines. The electric field of the first dipole is parallel to an electric field of the first set of the plurality of transmission lines, and an electric field of the second dipole is parallel to an electric field of the second set of the plurality of transmission lines.
1. An apparatus comprising:
a plurality of transmission lines;
a first dipole electrically connected to a first set of the plurality of transmission lines; and
a second dipole electrically connected to a second set of the plurality of transmission lines,
wherein the first dipole and the first set of the plurality of transmission lines share a first common plane of symmetry, and wherein an electric field of the first dipole and an electric field of the first set of the plurality of transmission lines are everywhere parallel to the first common plane of symmetry, and
wherein the second dipole and the second set of the plurality of transmission lines share a second common plane of symmetry, and wherein an electric field of the second dipole and an electric field of the second set of the plurality of transmission lines are everywhere parallel to the second common plane of symmetry.
2. The apparatus of claim 1 wherein at least one of the plurality of transmission lines includes a feed microstrip.
3. The apparatus of claim 1 wherein at least one of the plurality of transmission lines is disposed on a printed circuit board.
4. The apparatus of claim 1 wherein the first dipole includes a first conductor electrically connected to a first transmission line in the first set of the plurality of transmission lines and a second conductor electrically connected to a second transmission line in the first set of the plurality of transmission lines.
5. The apparatus of claim 4 wherein at least one of the first and second conductors is supported on a dielectric support structure.
6. The apparatus of claim 1 wherein the second dipole includes a first conductor electrically connected to a first transmission line in the second set of the plurality of transmission lines and a second conductor electrically connected to a second transmission line in the second set of the plurality of transmission lines.
7. The apparatus of claim 6 wherein at least one of the first and second conductors is supported on a dielectric support structure.
8. The apparatus of claim 1 wherein the electric field of the first dipole is orthogonal to the electric field of the second set of the plurality of transmission lines.
9. The apparatus of claim 1 wherein the electric field of the first dipole is orthogonal to the electric field of the second dipole.
10. The apparatus of claim 1 wherein the electric field of the second dipole is orthogonal to the electric field of the first set of the plurality of transmission lines.
11. The apparatus of claim 1 wherein the electric field of the first set of the plurality of transmission lines is orthogonal to the electric field of the second set of the plurality of transmission lines.
12. The apparatus of claim 1 further comprising:
a first balun associated with the first dipole; and
a second balun associated with the second dipole,
wherein the first balun is disposed in a first plane and the second balun is disposed in a second plane.
13. The apparatus of claim 12 wherein the first plane is different than the second plane.
14. The apparatus of claim 12 wherein the first and second planes are parallel to a ground plane, wherein the first plane is on a first side of the ground plane, and wherein the second plane is on a second side of the ground plane.
15. The apparatus of claim 12 wherein the first plane is parallel to a ground plane, and wherein the second plane is at an angle to the ground plane greater than zero.
16. The apparatus of claim 15 wherein the second plane is orthogonal to the ground plane.
17. The apparatus of claim 12 wherein at least one of the first and second baluns is of approximately one half wavelength or an odd multiple thereof.
18. The apparatus of claim 1 wherein the electric field of the first dipole is parallel to the electric field of the first set of the plurality of transmission lines.
19. The apparatus of claim 1 wherein the electric field of the second dipole is parallel to the electric field of the second set of the plurality of transmission lines.
20. The apparatus of claim 1 wherein the electric field of the first dipole and the electric field of the first set of the plurality of transmission lines are everywhere orthogonal to the second common plane of symmetry.
21. The apparatus of claim 1 wherein the electric field of the second dipole and the electric field of the second set of the plurality of transmission lines are everywhere orthogonal to the first common plane of symmetry.
22. A method comprising:
providing a plurality of transmission lines;
providing a first dipole electrically connected to a first set of the plurality of transmission lines;
providing a second dipole electrically connected to a second set of the plurality of transmission lines;
orienting the first dipole relative to the first set of the plurality of transmission lines such that the first dipole and the first set of the plurality of transmission lines share a first common plane of symmetry and such that an electric field of the first dipole and an electric field of the first set of the plurality of transmission lines are everywhere parallel to the first common plane of symmetry; and
orienting the second dipole relative to the second set of the plurality of transmission lines such that the second dipole and the second set of the plurality of transmission lines share a second common plane of symmetry and such that an electric field of the second dipole parallel to and an electric field of the second set of the plurality of transmission lines are everywhere parallel to the second common plane of symmetry.
23. The method of claim 22 wherein the electric fields of the first dipole and the first set of the plurality of transmission lines are orthogonal to the electric fields of the second dipole and the second set of the plurality of transmission lines.
24. The method of claim 22 further comprising:
providing a first balun associated with the first dipole; and
providing a second balun associated with the second dipole,
wherein the first balun is disposed in a first plane and the second balun is disposed in a second plane.