Patent ID: 6211835
Filing Date: 2001-04-03
Classification: H01Q,H04B,Y10S

Abstract:
An antenna system for use on a spacecraft comprising:a main reflector;a subreflector; and,a feed array comprised of a plurality of separate feeds arranged in a preselected configuration so that the feeds are aligned along a predetermined contour, said feed array, subreflector and main reflector oriented to define a side-fed dual reflector antenna geometry wherein said feed array is to a side of both said main reflector and said subreflector, each feed provides a separate illumination beam, the feed array is coupled to a feed network which acts to combine the illumination beams of clusters of a preselected number of feeds to produce a single composite illumination beam from each cluster,each composite illumination beam has a central ray which is directed to be incident upon a separate preselected location on said subreflector,the subreflector is configured to receive each composite illumination beam at said predetermined location on said subreflector and direct each said composite illumination beam towards said main reflector,the main reflector is positioned to receive each composite illumination beam from the subreflector and direct each composite illumination beam in a predetermined direction so that each composite illumination beam forms an antenna beam that impinges a predetermined coverage area on the Earth and each antenna beam defines a separate coverage cell in the coverage area, wherein the position and orientation of the feeds, the subreflector and the main reflector provides antenna beams within a preselected coverage area.