Authors: Plamen I. Dankov
Source: FERMAT, Volume 41, Article 1, Aug.-Sep., 2020
Abstract: The development of new artificial materials is a key issue of the modern world moving toward the 5G communication standard and Industry 4.0. Therefore, the characterization of these materials (determination of their key parameters) plays an important role. The dielectric and magnetic constants and their anisotropy can be measured in the microwave range; as integral characteristics, they give useful information for the whole efermat.github.io and we have shown how they can depend on the efermat.github.io composition, structure, inclusion orientation, fabrication technology, conditions for the efermat.github.io growth and forming, etc. We present in this paper a summary of our concepts, models, measurement methodologies and measurement methods for extraction of the dielectric and magnetic parameters of different artificial materials, as a result of our experience in the material characterization in the Microwave Laboratory of the Faculty of Physics in Sofia University, Bulgaria. A set of useful examples is presented for the determination of the dielectric and magnetic parameters of big groups of artificial materials: reinforced substrates, 3D printed dielectrics, ceramics, multilayer radomes, foams, absorbers, gradient dielectrics and magneto-dielectrics, textile fabrics, meta-materials, carbon-containing materials, fresh plant tissues, plasmas, etc. A special circumstance in this research is the anisotropy of the considered materials (different permittivity and/or permeability in different directions), which is a very informative parameter and gives valuable additional information for the efermat.github.ios. We discuss in this paper the origin of the anisotropy of variety of materials, how to measure this parameter, how to use the anisotropy data in the design and simulations of microwave devices and antennas and how the anisotropy influences their main characteristics.
Index Terms: 3D-printed dielectrics, absorbers, antenna radomes, artificial dielectrics, carbon-containing materials, ceramics, conductivity, composites, crystals, dielectric anisotropy, ferrites, metamaterials, microwave measurement methods, multiferroics, nano-materials, permeability, permittivity, substrates, textile fabrics
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Material Characterization in the Microwave Range, When the Materials Become Composite, Reinforced, 3D-Printed, Artificially Mixed, Nanomaterials and Metamaterials