Diffraction synthesis of reflector antennas: An efficient approach for the optimization procedure

Shaped reflector antennas for spacecraft applications have been designed using diffraction synthesis techniques based on optimization methods. These techniques are very demanding from a computational point of view and they rely on efficient numerical codes as the repeated evaluation of physical optics (PO) current integration is required. A reduction in the computing time can be achieved by an adequate starting point of the optimization procedure. In general, standard surfaces obtained by simple presynthesis analysis are used to initialize the iteration. The critical point of searching for a start is addressed in the present work by adopting a strategy that employs the reflector obtained from the geometrical optics (GO) synthesis to initialize the diffractive scheme. The same optimization scheme is used to solve the PO and GO steps. To illustrate the approach, it is applied to the design of a reflector antenna to satisfy the BRASILSAT satellite specifications.<>