Complementary wideband antenna
A complementary wideband antenna includes a planar dipole formed of two dipole sections and a shorted patch antenna located between the dipole sections, the dipole sections being spaced above a ground plane. A variety of different feed probe designs can be used to excite the antenna. The complementary wideband antenna has electrical characteristics including low back radiation, low cross polarization, a symmetrical radiation pattern, and is stable in gain and radiation pattern shape over the frequency bandwidth.
1. A wideband antenna comprising:
a planar dipole formed of two dipole sections and a shorted patch antenna element located between said dipole sections, said dipole sections being spaced a distance above a ground plane, wherein said shorted patch antenna element comprises first and second parallel vertical sections extending respectively from an edge of a respective dipole section to said ground plane, and a feed probe located between said vertical sections of said shorted patch antenna element.
2. An antenna as claimed in claim 1 wherein said vertical sections are rectangular.
3. An antenna as claimed in claim 2 wherein said rectangular vertical sections have a width equal to a width of said respective dipole sections.
4. An antenna as claimed in claim 2 wherein said rectangular vertical sections have a width less than a width of said respective dipole sections.
5. An antenna as claimed in claim 2 wherein said vertical sections are trapezoidal.
6. An antenna as claimed in claim 5 wherein said trapezoidal vertical sections have one side with a width equal to a width of said respective dipole sections.
7. An antenna as claimed in claim 1 wherein said feed probe comprises a first section extending vertically with respect to the ground plane parallel and proximate to said first vertical section of said shorted patch antenna, a second section extending parallel to said ground plane, and a third section extending towards said ground plane.
8. An antenna as claimed in claim 7 wherein said second section of said feed probe is spaced from said ground plane by the same distance as said dipole sections.
9. An antenna as claimed in claim 7 wherein said third section extends proximate and parallel to the second vertical section of the shorted patch antenna or at a small angle thereto.
10. An antenna as claimed in claim 1 wherein said feed probe comprises a coaxial feed extending from the ground plane substantially to the spacing of said dipole sections from said ground plane, and a probe comprising a portion extending parallel to said ground plane and a portion extending towards said ground plane and substantially perpendicular thereto.
11. An antenna as claimed in claim 1 wherein said feed probe comprises a microstrip transmission line extending from the ground plane substantially to the spacing of said dipole sections from said ground plane, and a probe comprising a portion extending parallel to said ground plane and a portion extending towards said ground plane and substantially perpendicular thereto.
12. An antenna as claimed in claim 1 wherein said feed probe comprises a first section extending perpendicularly to said ground plane and parallel to said first vertical section of said shorted patch antenna, and a second section extending parallel to said ground plane, said second section having a T-shape.
13. An antenna as claimed in claim 1 wherein said feed probe comprises a first section extending perpendicularly to said ground plane and parallel to said first vertical section of said shorted patch antenna, a second section extending parallel to said ground plane, and two vertical sections extending from said second section towards said ground plane.
14. An antenna as claimed in claim 1 wherein said dipole sections are rectangular.
15. An antenna as claimed in claim 1 wherein said dipole sections are polygonal.
16. An antenna as claimed in claim 1 wherein said dipole sections are triangular.
17. An antenna as claimed in claim 1 wherein said dipole sections are semi-circular.
18. An antenna as claimed in claim 1 further comprising dielectric material disposed in a space defined by said shorted patch antenna.
19. An antenna as claimed in claim 1 wherein said dipole sections are parallel to said ground plane.
20. An antenna as claimed in claim 1 wherein at least a portion of each of said dipole sections is angled relative to said ground plane.
21. An antenna as claimed in claim 1 wherein each of said dipole sections comprises a portion parallel to said ground plane and a portion perpendicular to said ground plane.