Dual-polarized fractal antenna feed architecture employing orthogonal parallel-plate modes
A multi-polarized continuous transverse stub (CTS) antenna includes a first feed network operative to at least one of receive or transmit a signal having a first polarization, and a second feed network different from the first feed network and operative to at least one of receive or transmit a signal having a second polarization different from the first polarization. At least one parallel-plate region is defined by a first plate structure and a second plate structure spaced apart from the first plate structure, where a first coupling structure connecting the first feed network to the parallel-plate region and a second coupling structure connecting the second feed network to the parallel-plate region. A common aperture is arranged on one side of the parallel-plate region, wherein wavefronts produced by the first and second coupling structures and propagated within the parallel-plate region radiate to free-space through the common aperture.
1. A multi-polarized continuous transverse stub (CTS) antenna, comprising:
a first feed network operative to at least one of receive or transmit a RF signal having a first linear polarization;
a second feed network oriented geometrically orthogonal from the first feed network and operative to at least one of receive or transmit an RF signal having a second linear polarization, generally with an orthogonal polarization relative to the first polarization;
at least one parallel-plate region defined by a first plate structure and a second plate structure spaced apart from the first plate structure;
a first coupling structure connecting the first feed network to the parallel-plate region;
a second coupling structure connecting the second feed network to the parallel-plate region; and
a common aperture arranged on one side of the parallel-plate region, wherein generally orthogonal wavefronts produced by the first and second coupling structures and propagated within the parallel-plate region radiate to free-space through the common aperture.
2. The CTS antenna according to claim 1 , further comprising a plurality of pucks spaced apart from one another, wherein the space between adjacent pucks defines the common aperture.
3. The CTS antenna according to claim 2 , wherein the plurality of pucks comprise a plurality of metallic members arranged in a lattice.
4. The CTS antenna according to claim 1 , wherein the plurality of pucks are rectangular in shape.
5. The CTS antenna according to claim 1 , wherein at least one puck of the plurality of pucks is dimensioned different from at least one other puck of the plurality of pucks.
6. The CTS antenna according to claim 1 , wherein the first and second coupling structures are connected to the parallel-plate region on a side of the parallel-plate region opposite the common aperture.
7. The CTS antenna according to claim 6 , wherein the first and second coupling structures are coupled to the second plate structure, and the common aperture is formed in the first plate structure.
8. The CTS antenna according to claim 1 , wherein the parallel-plate region comprises a plurality of parallel plate regions located between the common aperture and the first and second coupling structures, whereby each adjacent parallel plate region further couples the wavefronts within such parallel-plate region to the next adjacent parallel plate region via parallel plate layer transitions.
9. The CTS antenna according to claim 1 , further comprising a polarizer arranged adjacent to the common aperture and operative to change a polarization of the radiated antenna patterns.
10. The CTS antenna according to claim 1 , wherein the at least one parallel-plate region comprises a dielectric material arranged between the first plate structure and the second plate structure.
11. The CTS antenna according to claim 10 , wherein the dielectric material comprises at least one of a foam material or air.
12. The CTS antenna according to claim 1 , wherein the first feed network and the second feed network comprise at least one of a waveguide, a strip line, a suspended air stripline, or a microstrip transmission line.
13. The CTS antenna according to claim 1 , wherein the first and second coupling structures comprise waveguide-to-parallel-plate slot transitions.
14. The CTS antenna according to claim 1 , wherein the first polarization comprises vertical polarization and the second polarization comprises horizontal polarization.
15. The CTS antenna according to claim 1 , wherein the parallel-plate region comprises at least one groove arranged in a surface of one of the first plate structure or the second plate structure.