Patent ID: 6198455
Filing Date: 2001-03-06
Classification: H01Q

Abstract:
A variable beamwidth antenna system comprising:a subreflector comprising a sector of an ellipsoidal surface having foci at points O' and O;a main reflector comprising a sector of paraboloidal surface having a vertex V and having its focal point located at O';a feed horn having its phase center located at O;a main reflector displacement mechanism; anda feed horn displacement mechanism;wherein the RF feed horn is controlled by the feed horn displacement mechanism and which is moved a distance ""x"" closer to the subreflector, and the main reflector is controlled by the main reflector displacement mechanism which is moved a distance ""y"" away from the subreflector,wherein the displacements ""x"" and ""y"" satisfy the equation ##EQU3##and wherein ""c"" and ""d"" are the distance between the RF feed horn and the subreflector, and the distance between the focal point of the main reflector and subreflector, respectively, before the displacements of the RF feed horn and the main reflector.