Design of Circularly Polarized Mechanically Reconfigurable Reflectarrays for Satellite Communications and Power Transfer

This paper presents a methodology for designing circularly polarized mechanically reconfigurable reflectarrays with applications to wireless power transfer. It presents some basic theory on spectrally limited power transfer (i.e. how carrier tapers of non-timed arrays can lower channel efficiency). It derives a similarity transformation that converts the linearly polarized Floquet scattering matrix of a periodic unit-cell into right-handed and left-handed circular polarization. This technique leverages the conventional Jones basis and unity matrix for linear and circular polarizations and is inspired by radar polarimetry which has a similar congruence transformation. To illustrate the concepts, a concentric split-ring reflectarray unit-cell is designed, optimized, and simulated for the entire Ku-band. The proposed design is ultra-wideband over the 10 GHz to 15 GHz range and has low loss and depolarization properties. The unit-cell is used in a full reflectarray and simulated in Ansys HFSS to get directivity patterns for various frequencies.