학술논문

Variability in Specific Absorption Rate From Variation in Tissue Properties
Document Type
Periodical
Source
IEEE Journal on Multiscale and Multiphysics Computational Techniques IEEE J. Multiscale Multiphys. Comput. Tech. Multiscale and Multiphysics Computational Techniques, IEEE Journal on. 7:304-311 2022
Subject
Engineered Materials, Dielectrics and Plasmas
Fields, Waves and Electromagnetics
Components, Circuits, Devices and Systems
Computing and Processing
Mathematical models
Finite difference methods
Time-domain analysis
Three-dimensional displays
Standards
Uncertainty
Computational modeling
Biological effects of electromagnetic radiation
biological tissues
Monte Carlo methods
Specific absorption rate (SAR)
Stochastic finite difference time domain (S-FDTD) method
Language
ISSN
2379-8815
2379-8793
Abstract
This study evaluates the variance of specific absorption rate (SAR) due to expected variance in the dielectric properties of tissues in a 3D anatomical human head model exposed to a half-wave dipole antenna at 835 and 1900 MHz. Stochastic finite difference time domain (S-FDTD) is applied to calculate variations in the local SAR, and the 1- and 10-gram averaged SAR values. These are also compared at 835 MHz to variations found from Monte Carlo FDTD. It is found that for both frequencies dielectric property variance results in a variance of peak 1- or 10-gram SAR of approximately 30% to 55% of the mean SAR, depending on the frequency. These results show that to reach 95% confidence with the calculated SAR values for evaluating exposure guidelines, statistical variations in tissue electrical properties must be taken into account.