Wideband, Circularly Polarized, Large Multi-Faceted Reflectarray for Satellite Applications

This work presents an offset-fed, seven-faceted, hexagonal reflectarray (RA) with an aperture size of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$3050\lambda _{0}^{2}$ </tex-math></inline-formula> at <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$f_{0} \; = \; 50 \; \text {GHz}$ </tex-math></inline-formula> (this size is equivalent to a circular aperture with a diameter <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$62.3\lambda _{0}$ </tex-math></inline-formula>, or to a square aperture with a length of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$55.2\lambda _{0}$ </tex-math></inline-formula>). The antenna has a 1-dB gain bandwidth (BW) of 13.4%, a 3-dB gain BW of 25.6% (39.8 to 51.5 GHz), and maintains a pencil beam in the satellite Q- and V-bands. The design is circularly polarized and has an axial ratio (AR) of less than 1 dB at all frequencies. The article presents a methodology to design multi-faceted RA antennas minimizing the phase error and explores the array theory approach to evaluate this type of antenna.