Broadband Permittivity and Permeability Extraction of 3-D-Printed Magneto-Dielectric Substrates

• Published in: IEEE microwave and wireless components letters Vol. 31; no. 10; pp. 1174 - 1177
• Main Authors: Sorocki, Jakub, Piekarz, Ilona, Bozzi, Maurizio
• Format: Journal Article
• Language: English
• Published: IEEE 01.10.2021
• Subjects: 3-D printing; broadband material characterization; Impedance; magneto-dielectric substrates; Microstrip; microwave circuits; miniaturized antennas; Permeability; Permittivity; Programmable logic arrays; Substrates; Transmission line measurements
• ISSN: 1531-1309; 1558-1764
• DOI: 10.1109/LMWC.2021.3100394

A broadband microwave magneto-dielectric spectroscopy technique is introduced and dedicated to the characterization of 3-D-printed magneto-dielectric substrates. Complex permittivity and permeability are extracted for the material-under-test fabricated in the same manner and with the same orientation of the electro-magnetic (EM) field as in the intended applications that include, for example, miniaturized and efficient antennas. The information is derived from the measured characteristic impedance and propagation constant of a test microstrip transmission line. To exclude the influence of the coaxial-to-microstrip transitions, printed launchers are proposed with puzzle-like interlock to test substrate which is used together with a printed thru-reflect-line (TRL) de-embedding set. The presented technique was experimentally validated on an example of specialized magnetic polylactic acid (PLA) filament printed substrate in the frequency range 0.1-6 GHz and a reference PLA substrate measured with two different techniques to yield comparable results.