Broadband Characterization of 3D Printed Samples with Graded Permittivity

This work presents the broadband characterization of the dielectric permittivity of 3-D printed samples with infill ratios in the range 10%-100%. The procedure is based on the measured S-parameters of a microstrip line loaded with the material under test as a superstrate. Measurement results are within a 15% error margin related to theoretical models and narrow-band results recently reported, and provide useful information on how to obtain arbitrary dielectric constant out of a material with fixed properties.