Approach to Control Permittivity and Shape of Centimeter-Sized Additive Manufactured Objects: Application to Microwave Scattering Experiments

Controlling the electromagnetic properties of dielectric objects is demanded in microwave applications such as radar cross section (RCS) studies, metamaterial design, and antennas prototyping. Additive manufacturing has made fabrication desired shapes easier, but there still room for improvement controlling permittivity. This article proposes a novel approach to control permittivity 3-D printed objects, particular ones with low contrasts. The effective set by locally varying material density. object first meshed using tetrahedral meshing software. Then its air percentage controlled adjusting diameter cylinders, which are positioned at each edge mesh. By tuning volume fraction, one can achieve required Design, manufacturing, characterization steps discussed specific case spheres. With canonical shape, be directly retrieved comparing far-field scattering measurements Mie computations. Bistatic RCS simulations provided discussed. They enable us assess validity proposed methodology, good adequacy between adequately chosen unstructured air/material distribution, relative permittivity, homogenization object.