Tissue Parameters Influence on the Microwave Energy Absorption in Biological Objects

Abstract

This article is devoted to an investigation of electrophysicalparameters ofbiological tissue influence on 2. Numerical Method its absorption of microwave energy. The specific There are several methods for the computing the absorption rate (SAR) is the dosimetric quantity for electromagnetic field induced inside the biological objects. evaluation of microwave energy absorbed in biological One of the numerical methods, which makes a spatial tissue. Many parameters have effect on the SAR value, such discretization scheme of Maxwell's equations is FIT. It is as geometry of the part of the body, which is exposed to suitable method for computers and can solve various microwave energy, electrical parameters of body tissues, electromagnetic field problems in modeled situations that distance between the source ofenergy and surface ofbody, simulate real conditions. In contrast to some other geometry of the antenna etc. In this article, homogeneous numerical methods, FIT is applied to the integral form of spherical model of the human head is modeled in CST Maxwell's equations [1]: Microwave Studio program environment. The tissue parameters variation influence on SAR values is evaluated aB for 900 MHz, 1800 MHz and 2450 MHz frequencies JdEd=-df dA (1) utilized in communication, medical and other applications. AA A at fH.ds=||' +i 4rd (2) Keywords AA A t )( Microwaves, CST Microwave Studio, SAR, fjjdA =|PedV (3) modeling, biological objects. e av v

Finite Element Modeling of scattered electromagnetic waves for stroke analysis

“…1. The dielectric properties mainly the conductivity ( ) and the relative permittivity ( r ) for the different layers of the normal head at 1 GHz are got from a published data [5,6] and are presented in Table 1. Improved spatial resolution could be got at higher frequencies, however as the frequency increases the attenuation of the signal by the biological tissues also increase leading to reduced penetration depth.…”

“…The frequency dependence of the complex relative permittivity values governed by the Cole-Cole expression is given in (2) and the frequency dispersive nature of these biological tissues [6] due different frequencies ranging from 500MHz to 2GHz is shown in Fig.2 έ…”