Corrugated horn fed offset paraboloidal reflector

Claim 1

A high frequency antenna system for radiating and receiving electromagnetic energy comprising: a feed-horn having corrugations disposed on the interior conducting surface thereof; parabolic reflective means disposed opposite the open end of said feed-horn for reflecting spherical wave-front energy radiated from said corrugated feed-horn and for converting the energy into plane-wave-front energy, and wherein said feed-horn is disposed so that none of the plane-wave-front energy is intercepted by said feed-horn; whereby said corrugations cause low edge illumination of energy from said feed-horn incident on said parabolic reflective means; and further wherein said feed-horn has a feed element located at the origin of an orthogonal x, y, z, axis reference system, the axis of the horn coinciding with the x axis, said feed-horn having an angle α between the feed-horn interior surface and the x axis and a length 2 F (k 2 -1) 1/2 - (2FK); and said parabolic reflective means having a parabolic surface satisfying the equation x 2 + y 2 =4F(z + F) where F is the focal length of said parabolic surface, and K is equal to tanα; wherein spherical energy radiating from said feedhorn is converted to plane wavefront energy traveling in the direction of the x axis.