Additive Manufactured Matching Medium Design for Implant Communications

Habiboglu O., Akgun S., Cil E., AYDIN ÇİVİ H. Ö. , Dumanli S.

15th European Conference on Antennas and Propagation, EuCAP 2021, Düsseldorf, Germany, 22 - 26 March 2021 identifier


© 2021 EurAAP.The design of matching media with different dielectric constants for the use in implant communications is presented in this paper. Each medium consists of a three-dimensional printed honeycomb structure filled with a high dielectric lossless semi-liquid. The dielectric constant of the media is determined by the infill percentage of the honeycomb structure as well as the dielectric constant of both the semi-liquid and the material of the structure. An algorithm is developed that can specify values for the infill percentage to reach a target dielectric constant value from a given material and semi-liquid. For the measurements, several honeycomb structures with different infill percentages are fabricated with polylactic acid using additive manufacturing. Water-based semi-liquids are developed to fill the structures. The dielectric constants of the fabricated media are measured with a half-filled rectangular resonant cavity. The practical results indicate that target dielectric constants ranging from 8 to 34 are reached by using semi-liquids with dielectric constants ranging from 20 to 65 between 2.2 GHz-3.2 GHz. The practical results are also shown to be in good agreement with the numerical ones with an error of less than 9% for all different cases.