Reivindicaciones

1. A feeder system for dual reflector antennas, comprising: - a feed horn (2) coupled to a waveguide; and - a sub-reflector dish (10) having a frontal side (12) for reflecting radiation emitted by the feed horn, and a rear side (11), wherein the system is characterized in that it contains: - at least one first high-impedance surface disposed on the rear side of the sub-reflector dish. 2. A system as claimed in claim 1, wherein the first high-impedance surface comprises at least one axial corrugation. 3. A system as claimed in claim 1, wherein the first high-impedance surface comprises at least one choke of certain dimensions tuned to a critical frequency. 4. A system as claimed in any of the preceding claims, wherein the first high-impedance surface is defined by a first depth parameter, a second slot width parameter and a third wall width parameter. 5. A system as claimed in claim 4, wherein the first parameter, the second parameter and the third parameter have respectively a value of λ/4, λ/8 and λ/80 or greater. 6. A system as claimed in any of the preceding claims, wherein the first high-impedance surface comprises at least five chokes, wherein each of the chokes has dimensions different from or equal to the others. 7. A system as claimed in any of the preceding claims, further comprising at least one second high-impedance surface (31, 32) disposed at the waveguide. 8. A system as claimed in claim 7, wherein the second high-impedance surface comprises at least one array of side chokes (51) disposed exteriorly on the waveguide. 9. A system as claimed in any of the preceding claims, that further comprises support means for the sub-reflector dish. 10. A system as claimed in claim 9, wherein the support means are selected from among a radome (23), a dielectric element or lens (22) and a number of rods (24); 11. A system as claimed in any of the preceding claims, and further comprising a feed mast, where the waveguide is disposed interiorly along said feed mast. 12. A system as claimed in claim 11, and further comprising a main reflector dish (5), coupled at a first extremity of the feed mast, where the feed mast comprises two high-impedance surfaces (51, 52) with five chokes each; and where the sub-reflector dish is supported by a radome, in such a way that the frontal side of the sub-reflector dish is disposed in a position facing the feed horn that reflects the radiation towards the main reflector dish, and where the frontal side of the sub-reflector dish has an elliptical geometry.