2026-01-25
Characterization of Complex Permittivity Using Microwave Diffraction of Spheres
By
Progress In Electromagnetics Research Letters, Vol. 129, 9-14, 2026
Abstract
The determination of the complex permittivity of materials is a fundamental aspect of experimental electromagnetics. This study introduces a method that estimates the complex permittivity by comparing the measured bistatic field diffracted by spherical samples in an anechoic chamber with fields computed using Mie theory. The approach is applied to a molded PMMA sphere and two 3D-printed materials (Clear Resin V4.1 and Rigid 10K) over the 2-18 GHz band. The retrieved permittivity values show excellent agreement with reference data for PMMA and enable reliable characterization of low-loss 3D-printed materials, with uncertainties quantified from both experimental and numerical contributions. These results confirm the effectiveness of microwave-diffraction-based characterization and highlight promising perspectives for future investigations on an even larger frequency band.
Citation
Elio Samara, Jean-Michel Geffrin, and Amelie Litman, "Characterization of Complex Permittivity Using Microwave Diffraction of Spheres," Progress In Electromagnetics Research Letters, Vol. 129, 9-14, 2026.
doi:10.2528/PIERL25110306
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