Traceable Assessment of the Absorbed Power Density of Body Mounted Devices at Frequencies Above 10 GHz

Authors: Chitnis N, Karimi F, Kühn S, Fallahi A, Christ A, Kuster N

Year: 2025 Sep

Category: Bioelectromagnetics, Experimental Dosimetry

Journal: Bioelectromagnetics

DOI: 10.1002/bem.70018

URL: https://onlinelibrary.wiley.com/doi/10.1002/bem.70018

Abstract

Overview

This study introduces a comprehensive and traceable experimental methodology to assess absorbed power density (APD) from body-mounted devices operating at frequencies above 10 GHz—a critical frequency range for modern wireless technologies, including 5G. The method combines:

  • ✔️ A specialized miniaturized probe
  • ✔️ A novel composite phantom simulating human skin properties
  • ✔️ Advanced reconstruction and calibration techniques
  • ✔️ Rigorous validation processes using reference antennas

Findings

The proposed solution has been validated primarily for 24 to 30 GHz, but is extendable to 10–45 GHz, ensuring broad utility in current and next-generation wireless device testing. Key achievements include:

  • 🔹 Development of a composite phantom with enhanced penetration depth, mimicking human skin’s reflection/transmission coefficients for both propagating and evanescent electromagnetic modes.
  • 🔹 Reliable measurement of induced electromagnetic fields (EMFs) using a broadband probe, with a wide dynamic range and high spatial resolution—essential for regulatory type approval of mobile devices.
  • 🔹 Probe calibration in a low-uncertainty, traceable setup.
  • 🔹 System validation using reference antennas, demonstrating expanded uncertainty below 1.6 dB for peak APD and 1.5 dB for peak spatial-averaged APD (psAPD).

Summary of Impact

  • 🌟 First traceable, broadband APD assessment method for 10-45 GHz, validated for practical device testing.
  • 🌟 Composite phantom design that accurately replicates real-world skin exposure conditions.
  • 🌟 Reference-antenna-based validation that ensures unbiased, instrumentation-agnostic evaluation across realistic exposure scenarios.

Conclusion

This work provides a robust foundation for type approval and qualification of body-mounted wireless devices in conformance with international safety standards. By enabling precise APD measurements, the method ensures greater confidence in assessing potential health risks from electromagnetic field (EMF) exposure due to devices operating at millimeter-wave frequencies. Notably, accurate and traceable exposure assessment is vital for understanding, monitoring, and mitigating the health risks connected to EMF exposure from wireless technology.

absorbed power density body-mounted devices 5G skin dosimetry electromagnetic fields exposure assessment wireless safety
← Back to Stats