Multifocal reflector antennas with multiple subreflectors

The authors describe a focused multiple-beam reflector antenna consisting of a single offset-fed axisymmetric paraboloidal main reflector and multiple shaped subreflectors and feeds. Each pencil beam requires its own subreflector and feed unit, but duplicate feeds and subreflectors may share the main reflector to generate identical beams in different directions. The resulting beams may achieve high aperture efficiency. The principle of a dual-beam system which implements this approach is illustrated. The configuration of a Gregorian-type system that produces two identical unblocked beams 18 degrees apart is described to illustrate the approach.<>