Multiple-element beam steering antenna
View Patent ↗An antenna for receiving and/or transmitting circularly and linearly polarized RF signals includes a circularly polarized radiation element and a linearly polarized radiation element. The radiation elements are disposed co-planar and spaced apart from each other on a pane of glass. The linearly polarized radiation element is fed with a phase-shifted signal line. A ground plane is disposed parallel to the radiation elements to sandwich a dielectric of air. The antenna produces the effect of tilting a radiation beam from a higher to a lower elevation angle to achieve a higher gain at lower elevation angles.
1. A window having an integrated antenna, said window comprising:
a nonconductive pane;
a circularly polarized radiation element disposed on said nonconductive pane;
a linearly polarized radiation element having a geometric shape different from that of said circularly polarized radiation element, disposed on said nonconductive pane, and spaced from said circularly polarized radiation element such that a radiation beam produced by said antenna is tilted; and
a phase shift circuit electrically connected to said linearly polarized radiation element for phase shifting a base signal, having a phase angle β, by a certain angle Δβ to achieve a phase-shifted signal having a phase angle β+Δβ.
2. A window as set forth in claim 1 wherein said radiation elements are co-planar with each other.
3. A window as set forth in claim 1 wherein a surface area of said linearly polarized radiation element is less than a surface area of said circularly polarized radiation element.
4. A window as set forth in claim 1 wherein said linearly polarized radiation element is spaced from said circularly polarized radiation element in a range of 1/20 to ½ of a wavelength λ of a base signal to be received or transmitted by said antenna.
5. A window as set forth in claim 4 wherein said linearly polarized radiation element is spaced from said circularly polarized radiation element by about ⅕ of the wavelength λ.
6. A window as set forth in claim 1 further comprising a base signal line electrically connected to said circularly polarized radiation element and carrying said base signal having said phase angle β.
7. A window as set forth in claim 6 further comprising a phase-shifted signal line electrically connected to said linearly polarized radiation element and carrying said phase-shifted signal having said phase angle βΔβ.
8. A window as set forth in claim 7 further comprising a 90°-shifted signal line electrically connected to said circularly polarized radiation element and carrying a 90°-shifted signal having a phase angle β+90°.
9. A window as set forth in claim 8 further comprising a 90° hybrid electrically connected to said base signal line and said 90°-shifted signal line for phase shifting said base signal by 90° to achieve said 90°-shifted signal.
10. A window as set forth in claim 9 further comprising a ground plane spaced from and parallel to said radiation elements and having a first side and a second side.
11. A window as set forth in claim 10 further comprising a dielectric sandwiched between said first side of said ground plane and said radiation elements.
12. A window as set forth in claim 10 further comprising a circuit board connected to said second side of said ground plane.
13. A window as set forth in claim 12 wherein said signal lines, said 90° hybrid, and said phase shift circuit are disposed on said circuit board.
14. A window as set forth in claim 13 further comprising a plurality of pins disposed between said radiation elements and said circuit board electrically connecting said signal lines to said radiation elements.
15. A window as set forth in claim 12 further comprising an amplifier disposed on said circuit board and electrically connected to said base signal line for amplifying said base signal.
16. A window as set forth in claim 1 further comprising a ground plane spaced from and parallel to said radiation elements.
17. A window as set forth in claim 16 further comprising a dielectric sandwiched between said ground plane and said radiation elements.
18. A window as set forth in claim 17 wherein said dielectric is air.
19. A window as set forth in claim 1 wherein said circularly polarized radiation element has a rectangular shape with a first edge and a second edge perpendicular to said first edge.
20. A window as set forth in claim 19 wherein each edge of said circularly polarized radiation element measures about ½ of a wavelength λ of a base signal to be received or transmitted by said antenna.
21. A window as set forth in claim 1 wherein said linearly polarized radiation element has a rectangular shape with a third edge and a fourth edge perpendicular to said third edge.
22. A window as set forth in claim 21 wherein said third edge of said linearly polarized radiation element measures about 1/20 of a wavelength λ of a base signal to be received or transmitted by said antenna and said fourth edge of said linearly polarized radiation element measures about ½ of the wavelength λ.
23. A window as set forth in claim 21 wherein said third edge of said linearly polarized radiation element measures about 1/20 of a wavelength λ of a base signal to be received or transmitted by said antenna and said fourth edge of said linearly polarized radiation element measures about ¼ of the wavelength λ.
24. A window as set forth in claim 21 wherein said linearly polarized radiation element defines a slot having a length that measures about ½ of a wavelength λ of a base signal to be received or transmitted by said antenna.
25. A window as set forth in claim 1 wherein said nonconductive pane is further defined as a pane of glass.
26. A window as set forth in claim 25 wherein said pane of glass is further defined as automotive glass.
27. A window as set forth in claim 26 wherein said automotive glass is further defined as soda-lime-silica glass.
28. A window as set forth in claim 1 wherein said circularly polarized radiation element is formed of a single patch of electrically conductive material.
29. An antenna comprising:
a circularly polarized radiation element;
a linearly polarized radiation element spaced from said circularly polarized radiation element and having a geometric shape different from that of said circularly polarized radiation element; and
a phase shift circuit electrically connected to said linearly polarized radiation element for phase shifting a base signal, having a phase angle β, by a certain angle Δβ to achieve a phase-shifted signal having a phase angle β+Δβ.
30. An antenna as set forth in claim 29 wherein said radiation elements are co-planar with each other.
31. An antenna comprising:
a circularly polarized radiation element;
a linearly polarized radiation element having a geometric shape different from that of said circularly polarized radiation element and spaced from said circularly polarized radiation element such that a radiation beam produced by said antenna is tilted; and
a phase shift circuit electrically connected to said linearly polarized radiation element for phase shifting a base signal, having a phase angle β, by a certain angle Δβ to achieve a phase-shifted signal having a phase angle β+Δβ.
32. An antenna as set forth in claim 31 wherein said radiation elements are co-planar with each other.
33. An antenna as set forth in claim 31 wherein said linearly polarized radiation element is spaced from said circularly polarized radiation element in a range of 1/20 to ½ of a wavelength λ of a base signal to be received or transmitted by said antenna.
34. A window as set forth in claim 31 wherein said circularly polarized radiation element is formed of a single patch of electrically conductive material.
35. A window having an integrated antenna, said window comprising:
a nonconductive pane;
a circularly polarized radiation element disposed on said nonconductive pane;
a linearly polarized radiation element having a geometric shape different from that of said circularly polarized radiation element, disposed on said nonconductive pane, and spaced from said circularly polarized radiation element such that a radiation beam produced by said antenna is tilted;
a base signal line electrically connected to said circularly polarized radiation element and carrying a base signal having a phase angle β; and
a phase-shifted signal line electrically connected to said linearly polarized radiation element and carrying a phase-shifted signal having a phase angle β+Δβ.