The Conical horn reflector antenna, a.k.a conical cornucopia, is a modified version of the Pyramidal horn-reflector antenna already present in Antenna Magus.
The Conical cornucopia is a combination of a conical electromagnetic horn and a parabolic reflector - hence horn reflector. The conical cornucopia has found preference over its pyramidal counterpart due to structural advantages and the absence of the high diffraction lobes which the pyramidal cornucopia produces at 90 degrees [Johnson].
The antenna has no frequency-sensitive elements, so performance bandwidth is limited only by the feed waveguide; and linear and circular polarization is possible. Since the aperture is not partially obstructed, as is often the case with ordinary front-fed dishes, aperture efficiencies of 80%, as opposed to 55-60% for front-fed dishes, may be achieved. The disadvantage is that it is far larger and heavier for a given aperture area than a parabolic dish....Total gain pattern at the center frequency Typical gain versus angle performance