الفهرس 
SOLUTION OF MAXWELL’S EQUATIONS IN DIFFERENTOnly 14 pages are availabe for public view
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Abstract
With the wide spread usage of Cellular telephone (GSM) in EGYPT, many questions have arised about the influence of these telephones on the human tissues. In this research, we have studied the effect of transient electromagnetic fields on the human head. Both rectangular and cylindrical coordinates were considered with different signal shapes in order to study the effect of each signal at a particular frequency on the human head, and hence, the signal with minimum effect can de determined. Those signals are a half sine wave at 900 MHz, a Mexican hat signal multiplied by a half sine wave at 900 MHz and a Gaussian signal multiplied by a half sine wave at 900 MHz. This thesis consists of six chapters that cover the whole subject of interest.
In chapter one, we introduce the FDTD method as an efficient technique to solve Maxwell’s equations numerically in rectangular coordinates in any medium including isotropic media, inhomogeneous media with space dependent electrical parameters and media with time dependent electrical parameters. Also the Yee mesh showing the field components distributed on the three dimensional space is considered.
Chapter two is concerned with a careful study of the Finite Difference Time Domain technique to deal with dispersive media. Since the electrical parameters of these media vary continuously with frequency, the normal FDTD was not able to solve such problems. An algorithm called (FD)2 TD technique is introduced to deal with dispersive media. The vector difference equations in this case are reported.
In chapter three, we introduce two methods to truncate the computational domain. The first is the Mur Absorbing Boundary Conditions and second is the Retarded Time ¬Absorbing Boundary Conditions RT-ABC. Generally absorbing boundary conditions arc very important in FDTD computations. When they are used both the computational domain size and the computational time decrease. This enhances the efficiency of the computational process.
In chapter four, we introduce two models for the human head, namely, a homogeneous and a heterogeneous model. To illustrate the effect of wavelength to grid size ratio on the accuracy of the results, each of these two models is implemented.