Estimation of Dielectric Property for Biological Tissues by Multi-Frequency Approximation


Aydinalp C., Dilman I., Joof S., Yılmaz Abdolsaheb T., Çayören M., Akıncı M. N.

2023 International Applied Computational Electromagnetics Society Symposium, ACES-Monterey 2023, California, United States Of America, 26 - 30 March 2023 identifier

  • Publication Type: Conference Paper / Full Text
  • Doi Number: 10.23919/aces57841.2023.10114706
  • City: California
  • Country: United States Of America
  • Keywords: microwave material characterization, open-ended coaxial probes
  • Istanbul Technical University Affiliated: Yes

Abstract

This paper investigates a new method to calculate the dielectric property (DP) of biological tissues with the open-ended coaxial probes (OECP). The DP of tissues is a continuous function of frequency which can be represented with different dielectric relaxation models. Thus, the accuracy of DP measurements can be increased by enforcing such spectral continuity using the Cole-Cole model. A cost functional based on an admittance integral was calculated at the tip of the OECP. Then, Cole-Cole parameters ( epsilon_ infty, epsilon_s, tau, alpha and sigma) were applied into the admittance integral to solve a set of nonlinear equations. The OECP, biological tissues and calibration materials were simulated using Ansys HFSS simulation program from 0.5 to 6 GHz frequency range with 0.25 GHz steps (23 frequency points). Finally, the accuracy of results was compared with data obtained from literature.