Advanced Synthesis of Reflectarrays using a Spherical Mapping of the 2 nd Order Phoenix Cell

A general synthesis approach is proposed for reflectarrays using second order Phoenix cells. It relies on an original spherical representation that transforms the optimization domain in a continuous and unbounded space with reduced dimension. This makes the synthesis problem simpler and automatically guarantees smooth variations in the optimized layout. The proposed mapping is combined with an ANN-based behavioral model of the cell and integrated in a min/max optimization process. As an application, a contoured beam for space communication in the [3.6-4.2] GHz band is considered. The gain improvement compared to an initial Phase Only synthesis (POS) is up to 1.62 dB. Full wave simulation of the final array is provided as a validation.