Abstract: A mechanically scanned reflector antenna system that produces a compact swept diameter and overall height, which is ideally suited for use on the external surface of a high speed mobile platform where a low profile, lightweight antenna is needed. The antenna system includes a main reflector and a subreflector both formed from composite materials. A support assembly includes a pair of arms that cantilever the main reflector forwardly of a base portion of the support assembly such that a portion of the main reflector can be positioned below an upper surface of the base portion. This enables the vertical height of the swept arc of the main reflector to be reduced when the main reflector is rotated about its elevation axis. The assembly provides an even more compact system that can be enclosed within a smaller radome when the system is employed on an external surface of a high speed mobile platform.

Abstract: An apparatus and method for forming a cassegrain reflector antenna that allows an extended length feed horn to be employed without increasing an overall depth of the antenna. This enables the swept diameter of the antenna to be maintained at a minimum comparable to an antenna system using a standard length feed horn. The antenna system employs a hole at a vertex of the main reflector of the antenna system. The elongated feed horn is mounted at the vertex such that a major portion of its length projects outwardly form a rear surface of the main reflector. Antenna electronics components can be mounted on a neck of the feed horn or alternatively on a rear surface of the main reflector. Since the elongated feed horn does not increase the overall depth, and thus the swept arc of the antenna, the size of the radome needed to cover the antenna can be kept to a minimum size comparable to that required for reflector antennas employing conventional, standard length feed horns.