Vol. 1 No. 2 (2015): METODE FINITE-DIFFERENCE TIME-DOMAIN UNTUK ANALISI PROPAGASI GELOMBANG PADA BUMBUNG GELOMBANG PERSEGI DENGAN SISIPAN MATERIAL DIELEKTRIK ANISOTROPIK

One of the most popular techniques to solve electromagnetics problems numerically is using a finite-difference time-domain (FDTD) method. It has been successfully applied to an extremely wide variety of problems, such as scattering from metal objects and dielectrics, antennas, microstrip circuits, radio communications, and electromagnetic absorption. The main reason of method resides in the fact that the method itself is extremely simple, even for programming in a 3 dimensional (3D) system. In this thesis, analysis of wave propagation based on FDTD method for a rectangular waveguide which is loaded with anisotropic dielectric material which is numerically investigated. The wave equation and modes that appear in the waveguide are analyzed theoretically in which the results are applied to validate and verify the numerical result obtained from FDTD method. The result shows a good agreement between analytical and numerical results. On this thesis, FDTD method has also been used to extract the scattering paramter of anisotropic dielectric material loaded on a rectangular waveguide. The principal used to analyze the EM wave from FDTD simulation are wave orthogonality and discontinuity inside a waveguide cavity. To validate the result from FDTD method, another simulation with HFSS has been done. The results shows a good agreement with some difference on the S-parameter curve. The difference appears because the numerator on the equation to calculate the incident and reflection wave tend to become very small with the increase of the frequencies that are being calculated. Another source of the difference is the effect of higher mode that appears on the waveguide cavity, and also the irregularity of EM field when loaded with anisotropic material.