Comparison of numerical and measurement methods of SAR of ellipsoidal phantoms with muscle tissue electrical parameters

Abstract

Purpose

The assessing of the specific absorption rate (SAR) of living organisms or phantoms is difficult to realize and this paper seeks to do this. SAR much more precisely describes the energy absorbed by biological objects than values of electric field strength (E [V/m]) or power density (S [W/m²]) measured at the point of exposition. However, for living objects the assessing of SAR is not an easy task by measuring methods or even in calculation evaluations. Numerical techniques, especially the finite‐difference time‐domain method (FDTD), offer different possibilities of calculations. The important problem with FDTD method introduced to lossy objects with complex shapes is that this method is not verified with the measuring data.

Design/methodology/approach

In this work the results of calculations and measuring data of ellipsoidal phantoms filled with specimen of electrical parameters like muscle tissue are presented. The calculations of SAR have been realized for two cases, e.g. for plane wave incident and for waveguide condition. Measurements for verifying the obtained data were done by waveguide method. The comparison of numerical (the package CONCERTO (Vector Fields Ltd)) and measurement methods were done at frequencies 900 and 1,800 MHz.

Findings

Calculations of SAR of lossy objects by FDTD method have been confirmed by measurements and analytical method of calculations. This documents that the package CONCERTO (Vector Fields Ltd) (Concerto User Guide) can be used for such calculations.

Originality/value

This paper presents the results of calculations of SAR of ellipsoidal phantoms filled with specimens of electrical parameters of equivalent muscle tissue.

Citation

Kubacki, R., Sobiech, J., Kieliszek, J. and Krawczyk, A. (2006), "Comparison of numerical and measurement methods of SAR of ellipsoidal phantoms with muscle tissue electrical parameters", COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, Vol. 25 No. 3, pp. 691-696. https://doi.org/10.1108/03321640610666853