Double balun dipole
View Patent ↗A double balun dipole antenna element includes a dielectric substrate having a first surface and an opposing second surface, a pair of coplanar Marchand baluns positioned in a mutually antiphase configuration on the first and second surfaces, and at least one feed line connected to the pair of Marchand baluns. A doubly polarized antenna element includes a pair of orthogonally interleaved double balun dipole antenna elements, which can be further configured into an array of such antenna elements.
1. A double balun dipole antenna element, comprising:
a dielectric substrate having a first surface and an opposing second surface;
a pair of coplanar Marchand baluns positioned in a mutually antiphase configuration on the first and second surfaces; and
at least one feed line connected to the pair of Marchand baluns.
2. An antenna element as in claim 1 , wherein each Marchand balun comprises:
a short circuited slotline stub on the first surface and wherein the first surface includes a conducting layer adjacent to each short circuit stub; and
an open circuited conductor stub positioned on the second surface and wherein the second surface also comprises the dielectric substrate.
3. An antenna element as in claim 2 , wherein the substrate has a leading edge and a trailing edge, the feed line includes a feed port positioned at the trailing edge, and the short circuited slotline stubs are mutually parallel and form an inverted U shape connected by an open-circuited slot terminating at the leading edge.
4. An antenna element as in claim 3 , wherein each short circuited slotline stub is the same electrical length and one is bent at about a 90 degree angle so as to fit both short circuited slotline stubs completely within a perimeter of the first surface.
5. An antenna element as in claim 1 , wherein each Marchand balun has a separate feed line.
6. A doubly polarized antenna element, comprising a pair of orthogonally interleaved double balun dipole antenna elements, wherein each antenna element comprises:
a dielectric substrate having a first surface and an opposing second surface;
a pair of coplanar Marchand baluns positioned in a mutually antiphase configuration on the first and second surfaces; and
at least one feed line connected to the pair of Marchand baluns.
7. An antenna element as in claim 6 , wherein each Marchand balun of each antenna element comprises:
a short circuited slotline stub on the first surface and wherein the first surface includes a conducting layer adjacent to each short circuit stub; and
an open circuited conductor stub positioned on the second surface and wherein the second surface also comprises the dielectric substrate.
8. An antenna element as in claim 7 , wherein the substrate has a leading edge and a trailing edge, the feed line includes a feed port positioned at the trailing edge, and the short circuited slotline stubs are mutually parallel and form an inverted U shape connected by an open-circuited slot terminating at the leading edge.
9. An antenna element as in claim 8 , wherein each short circuited slotline stub is the same electrical length and one is bent at about a 90 degree angle so as to fit both short circuited slotline stubs completely within a perimeter of the first surface.
10. An antenna element as in claim 6 , wherein each Marchand balun has a separate feed line.
11. An antenna array, comprising: a plurality of pairs of orthogonally interleaved double balun dipole antenna elements, wherein each antenna element comprises:
a dielectric substrate having a first surface and an opposing second surface;
a pair of coplanar Marchand baluns positioned in a mutually antiphase configuration on the first and second surfaces; and
at least one feed line connected to the pair of Marchand baluns.
12. An antenna array as in claim 11 , wherein each Marchand balun of each antenna element comprises:
a short circuited slotline stub on the first surface and wherein the first surface includes a conducting layer adjacent to each short circuit stub; and
an open circuited conductor stub positioned on the second surface and wherein the second surface also comprises the dielectric substrate.
13. An antenna element as in claim 12 , wherein the substrate has a leading edge and a trailing edge, the feed line includes a feed port positioned at the trailing edge, and the short circuited slotline stubs are mutually parallel and form an inverted U shape connected by an open-circuited slot terminating at the leading edge.
14. An antenna array as in claim 13 , wherein each short circuited slotline stub is the same electrical length and one is bent at about a 90 degree angle so as to fit both short circuited slotline stubs completely within a perimeter of the first surface.
15. An antenna array as in claim 12 , wherein the array comprises a plurality of rows of elements and each row further comprises a matching end tab at each end of each row.
16. An antenna array as in claim 11 , wherein each Marchand balun has a separate feed line.