We demonstrate a new method for realizing modified Luneburg lens antennas with nearly continuously graded permittivity profiles in three‐dimensions. The method used a quasi‐conformal transformation optics (QCTO) approach to modify the geometry and permittivity of a spherical Luneburg lens to have a flat surface for convenient integration of antenna feeds. The modified lens was then fabricated using Fused Deposition Modeling (FDM) printing with an effective media approach that employs space‐filling curves. The method was validated by designing and fabricating a modified Luneburg lens antenna designed to operate in the Ka‐band. The antenna performance of the sample was measured experimentally and shown to compare well to predicted results using full wave simulations. The device was able to achieve a reasonably high degree of beam steering (ie, −55° to +55°) over the entire Ka‐band. We believe this new approach provides a cost‐effective and scalable means of realizing practical passive beam steering lenses that operate over a broad range of frequencies.
A method for the fabrication of graded dielectrics within a structural composite is presented. This system employs an ultrasonic powder deposition head to print high dielectric powders onto a woven fabric composite substrate. It is shown how this system can integrate 3D variations of dielectric properties at millimeter resolution within a mechanically rugged substrate. To conclude, the system’s practical application is demonstrated with experimental results from a graded index lens.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.