Additive Manufacturing of Luneburg Lens Antennas Using Space-Filling Curves and Fused Filament Fabrication

We demonstrate a new method for realizing Luneburg lens antennas with nearly continuously graded permittivity profiles in three dimensions. The method combines fused filament fabrication, a nearly ubiquitous additive manufacturing technique, with an effective media approach that employs space-filling curves. We experimentally validate our design methodology by fabricating and characterizing two Luneburg lenses designed to operate at separate frequency bands (26–40 GHz and 70–110 GHz) with antenna gains of 20 and 24 dBi, respectively. The results demonstrate good agreement with rigorous electromagnetic simulations. We also demonstrate the ability to passively beam steer over a wideband of operation (26–40 GHz and 70–110 GHz) with less than 0.5% power loss due to dielectric material losses within the Luneburg lens.