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arXiv · 2603.09807

Experimental Characterization of Biological Tissue Dielectric Properties through THz Time-Domain Spectroscopy

Elisabetta Marini·Silvia Mura·Marco Hernandez·Matti Hamalainen·Maurizio Magarini
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Abstract

Terahertz (THz) radiation provides a non-ionizing, highly sensitive probe of the dielectric properties of biological tissues. In this study, we present a comprehensive experimental characterization of dielectric properties using pork skin tissue, a widely used surrogate for human tissue, as a biological sample. Measurements are conducted employing THz time-domain spectroscopy in the 0.1-11 THz frequency range with photoconductive antennas for both signal generation and detection. Frequency-dependent refractive indices, absorption, and complex permittivity are extracted from transmitted time-domain signals. Our results confirm strong absorption and low transmittance at low THz frequencies due to water content, while highlighting frequency-dependent dispersion and narrowband transmission features at higher frequencies. This work provides one of the first extended-frequency datasets of biological tissue dielectric properties, supporting realistic channel modeling for the design and development of intra-body nanosensor networks in the THz band.

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Elisabetta Marini, Silvia Mura, Marco Hernandez, Matti Hamalainen, Maurizio Magarini. 2026-03-10. Experimental Characterization of Biological Tissue Dielectric Properties through THz Time-Domain Spectroscopy. https://arxiv.org/abs/2603.09807

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