Asymptotic analysis of scattering from reflectarray antennas for the near-field focused applications

The scattering mechanisms of reflecting arrays illuminated by the radiation of line source are summarized for a general near-field focus problem. In particular, the phenomena are interpreted by the ray decompositions of Floquet waves and result in the solutions, analogous to the ordinary UTD-type formulations for the phased array antennas with a proper parameter mapping. The ray phenomena however exhibit different characteristics with this reflecting array problem, which will be theoretically investigated with numerical examples presented to demonstrate the scattering ray mechanisms.