Studies on planar reflectarrays with spherical-phase distribution for 2-D beam-scanning

Planar reflectarray antennas with spherical phase distribution are studied in this paper. Analytical expressions are derived for the aperture phase distribution, and the restricted aperture approach is used to minimize the effects of spherical aberration. The optimal feed position is determined by means of a phase error analysis, and a planar reflectarray with 30 dB gain and 30 degrees elevation coverage is studied for two-dimensional beam-scanning. These studies show that planar reflectarrays with spherical phase distribution can be a suitable choice for high-gain two-dimensional beam-scanning applications.