Dual-polarization rippled reflector antenna
An antenna may include a reflector and a multi-band feed assembly. A support member may be coupled to the multi-band feed assembly to orient the multi-band feed assembly for direct illumination of the reflector. The multi-band feed assembly may include first and second feeds, each having a respective septum polarizer coupled between a respective common waveguide and a respective pair of waveguides. A housing of the support member may contain the respective septum polarizers and the respective pairs of waveguides.
1. An antenna comprising:
a single reflector having a shaped surface, wherein the shaped surface comprises a plurality of ripples between a center and an edge of the single reflector, and at least one of the plurality of ripples includes a first portion and a second portion on opposing sides of a parabolic surface defined by the plurality of ripples;
a feed comprising a septum polarizer coupled between a common waveguide and a first waveguide and a second waveguide of a pair of waveguides; and
a support member to orient the feed for direct illumination of the shaped surface of the single reflector, the support member comprising a housing containing the pair of waveguides and the septum polarizer.
2. The antenna of claim 1 , wherein the shaped surface is a continuous surface between the center and the edge of the single reflector.
3. The antenna of claim 1 , wherein the plurality of ripples define a profile that is symmetrical about a central axis of the single reflector.
4. The antenna of claim 1 , wherein the plurality of ripples is a first plurality of ripples defining a first profile of the shaped surface between the center and a first location at the edge of the single reflector, the shaped surface further comprises a second plurality of ripples defining a second profile of the shaped surface between the center and a second location at the edge of the single reflector, and the second profile is the same as the first profile.
5. The antenna of claim 1 , wherein the plurality of ripples is a first plurality of ripples defining a first profile of the shaped surface between the center and a first location at the edge of the single reflector, the shaped surface further comprises a second plurality of ripples defining a second profile of the shaped surface between the center and a second location at the edge of the single reflector, the second profile different than the first profile.
6. The antenna of claim 5 , wherein the first plurality of ripples has a first deviation from the parabolic surface at a particular distance from center, and the second plurality of ripples has a second deviation from the parabolic surface at the particular distance that is different than the first deviation.
7. The antenna of claim 1 , wherein a first ripple of the plurality of ripples has a first maximum deviation from the parabolic surface, and a second ripple of the plurality of ripples has a second maximum deviation from the parabolic surface is less than the first maximum deviation.
8. The antenna of claim 7 , wherein the first ripple is closer to the center of the single reflector than the second ripple.
9. The antenna of claim 7 , wherein the first ripple is closer to the edge of the single reflector than the second ripple.
10. The antenna of claim 1 , wherein the center is a location on the shaped surface at which boresight of the feed is oriented via the support member.
11. The antenna of claim 1 , wherein the support member extends through an opening of the single reflector.
12. The antenna of claim 11 , wherein the opening is at a periphery of the single reflector.
13. The antenna of claim 1 , wherein the support member has an arcuate shape.
14. The antenna of claim 13 , wherein the support member has a leading edge along the arcuate shape that is oriented towards the single reflector and has a tapered cross-section.
15. The antenna of claim 14 , wherein the tapered cross-section is beveled.
16. The antenna of claim 14 , wherein the tapered cross-section mitigates scattering interaction between the support member and the single reflector.
17. The antenna of claim 14 , wherein the support member has a trailing edge oriented away from the single reflector having a different cross-section than the leading edge.
18. The antenna of claim 17 , wherein the trailing edge has a flat cross-section.
19. The antenna of claim 1 , wherein the support member is within a swept volume of the single reflector.
20. The antenna of claim 1 , wherein the edge of the single reflector is non-circular.