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

2026-03-10

AI Summary

This study addresses the scarcity of experimental data on the dielectric properties of biological tissues in the terahertz (THz) band, a critical gap hindering accurate channel modeling for in-body nanoscale communication. Utilizing a photoconductive antenna-based THz time-domain spectroscopy system, the work presents a comprehensive broadband characterization of porcine skin—used as a human tissue surrogate—across the 0.1–11 THz range. It reports, for the first time, an experimental dataset of complex permittivity, refractive index, and absorption coefficient extending up to 11 THz. The results reveal strong water-induced absorption at lower frequencies, alongside pronounced dispersion and narrowband selective transmission characteristics at higher frequencies. These findings provide essential empirical foundations and critical parameters for the development of realistic THz in-body communication channel models.

Technology Category

• Computer Vision: Medical and Biological Imaging
• Cognitive Modeling & Cognitive Systems: Neural Spike Coding
• Machine Learning: Kernel Methods

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Web performance, measurement, and characterization
• Security and Privacy: Large-scale security measurements
• Web Mining and Content Analysis: Web measurements

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.

Problem

• THz time-domain spectroscopy
• biological tissue
• dielectric properties
• complex permittivity
• intra-body nanosensor networks

Innovation

• THz time-domain spectroscopy
• dielectric properties
• biological tissue
• complex permittivity
• intra-body nanosensor networks