Equivalent circuit modeling of active reflectarray element with Varactor loaded radial phasing line

A very simple modeling approach is adopted in this paper to perform a fast preliminary investigation of a novel broadband varactor loaded phasing line, specifically designed to add frequency agility features to an existing active aperture-coupled reflectarray cell. The proposed circuit-model approach is adopted to compare frequency performances of radial and linear phasing line geometries. The method allows to demonstrate the effective contribution of a radial line geometry for the enhancement of the unit cell frequency operational range.