Ray-tracing analysis of the transmission performance of curved fss

Finite frequency selective surfaces (FSS) embedded in a curved dielectric are analysed using the ray-tracing technique. The FSS is treated as an infinitesimally thin interface with known complex reflection and transmission coefficients subjected to multiple interactions with rays internally reflected within the dielectric; Results for flat surfaces agree well with those computed using a full modal analysis. The transmission properties of such arrays are studied as the curvature is steadily increased for the case of paraboloids illuminated by plane waves, and also when enclosing a finite aperture-type antenna. The results obtained are validated by measurement.