Reconfigurable contour beam-reflector antenna synthesis using a mechanical finite-element description of the adjustable surface

A synthesis technique based on a mechanical finite-element (FEM) surface description of dual-offset reflector (DOSR) surfaces is described. This technique is used to implement a reconfigurable contour beam for a geostationary satellite application. The mechanical finite-element description of the surface takes into account the mechanical properties of the reflector surfaces and the effect of a finite number of forces applied at control points on the surface. Mechanical adjustment is achieved using high-deflection stacked piezoelectric actuators attached to the rear of a lightweight flexible subreflector surface. Both the main and subreflector surfaces are shaped for an initial required geographical coverage zone and then the main reflector surface is assumed to be fixed in shape. The variable shape subreflector is then synthesized to achieve the desired illumination for different geographical regions and different geostationary positions. Based on a study of the effect of the mechanical properties of the subreflector surface and actuator number and placement, a practical design has been completed and the ability to reconfigure the beam has been verified.