Reconfigurable contour beam reflector antennas using adjustable subreflector and adjustable single feed

A synthesis technique and mechanical design for a reconfigurable contour beam dual-offset-reflector antenna for satellite application are described. Mechanical adjustment is achieved by attaching high-deflection stacked piezoelectric actuators to the rear of a lightweight flexible subreflector surface. Both the main and subreflector surfaces are shaped for an initial required geographical coverage, and the main reflector surface is then assumed to have a fixed shape. The variable shape subreflector is then synthesized to achieve required coverage for different geographical regions and different geostationary positions. To develop this system, the following methodology was developed. Based on the required subreflector surface displacement, mechanical finite-element analysis was conducted on the reflector surface, and an actuator placement study was completed. The surface deflections attained from mechanical actuation were then compared to the required surface deflections. The achieved subreflector surface error was calculated, as well as the effect of the error on the radiation pattern. The results show that one can achieve acceptable performance from a finite amount of actuators on a reflector surface. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 21: 436–446, 1999.