SE356641

1374567 Aerials TELEFON AB L M ERICSSON 19 April 1973 [24 April 1972] 19196/73 Heading H4A A Cassegrain-type aerial arrangement comprises a polarization-turning main reflector 11, a polarization-dependent sub-reflector 12, and a feeder 10 having an oval aperture 20, which faces the sub-reflector. As described, the aperture is elliptical, with its major axis horizontal, and vertically polarized waves are radiated therefrom. The sub-reflector 12 is in the form of a plastics material shell, in which vertical wires are embedded. The waves from the feeder 10 are directed by the sub-reflector to the main reflector 11, where they are collimated and their polarization is changed to horizontal, so that they are then able to emerge through the subreflector. The oval aperture in the feeder is stated to reduce side lobes. One or more dividing walls may be provided, such as a central septum 21, which allows operation in a difference-mode.