Refractive Index Engineering in 3D Printed Dielectric Substrates for Beam Steering

3D printing is used to realize index-gradient and index-modulated dielectric media. The engineered media are associated to uniform inductive and capacitive grids to realize partially reflecting surfaces with either phase gradient or phase modulation along the dielectric-metal structures. Fabry-Perot cavity antennas utilizing the phase-engineered partially reflecting surfaces are designed, fabricated and measured. Simulated and measured performances show that the radiated beam is steered from boresight to a desired off-normal direction.