Performance Improvement for a Varactor Loaded Reflectarray Element

The application of varactors as phase shifting devices in reflectarrays has received considerable attention because it represents a low cost and low complexity solution to the realization of scanning antennas. Main issues related to the design of varactor loaded reflectarrays are the correct characterization of the unit cell and the limited phase range achievable by changing the polarization voltage of the device. The contribution presented in this paper attempt to cover both aspects presenting the optimization of the position of the varactor with both simulations and measurements obtained with a waveguide simulator.