الفهرس 
Solution of Maxwells Equation in an Isqtropic Medium Using the Finite Difference TimeOnly 14 pages are availabe for public view
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Abstract
Dielectric resonators are now widely used to replace bulky and expensive metallic cavities in microwave circuit design. Recently, more attention has been focused on the study of the characteristic of dielectric resonators when used as radiators. The main disadvantage of using the dielectric resonators as radiating elements is the difficulty in mathematical analysis. Now and with the growth happened in the computers’ power associated with a big growth in the numerical algorithms for solving radiation problems, the Finite Difference Time Domain (FDTD) method has taken its chance to demonstrate its power in simplifying this problem. In this thesis, we shall use the FDTD method to solve the problem of the Dielectric Resonator Antenna (DRA) using different shapes of the antennas and different types of signals. This thesis consists of eight chapters covering the subjects connected to this problem. In chapter one, we introduce the FDTD as an efficient technique discovered by Yee in 1966 to solve Maxwell’s equations numerically in an isotropic medium, where the electrical parameters (µ, έ and σ) are independent of time and space, using rectangular coordinates. Yee could solve this problem by replacing the differential equations of Maxwell by a set of finite difference equations. Chapter two completes the work of Yee by expanding the method to solve Maxwell’s equations in anisotropic media where the electrical parameters (11, E and cr) are functions of time or space Chapter three is devoted to solve the main problem of the FDTD that is the absorbing boundary conditions (ABC), which simulates the extent of the problem’s. domain to infinity. We consider two kinds of absorbing boundary conditions. The first ABC is introduced by G. Mur and the other one is a modification of Mm’s, which is introduced by Z. P. Liao. In chapter four, we introduce two models to simulate the process of feeding signals to antennas in the FDTD method.