Abstract |
When designers design products, they will avoid the distortion of signal as possible. However, they sometimes may make input signal propagate in unusual form. For instance, military airplanes can be coated with special material on the body surface, and it cannot cause normal reflection and scattering when radiations touch on the body surface. Therefore, radars will not receive expected information to predict their movements. This special material is commonly known as invisible material, and anisotropic material is one of the choice of materials. FDTD is widely used in analysis of electromagnetic wave. Since there are a few disadvantages on the analysis of anisotropic material with Yee’s grid, Lebedev grid becomes famous because of its better results on the same issue. However, except the advantages, Lebedev grid may face a lot of trouble, such as bigger numerical distortion and complicated excitation. As a result, this thesis will provide a method which combines two kinds of grid that have been mentioned above to have both of their advantages and achieve higher accuracy and efficiency. Therefore, the issue of anisotropic material can be solved more efficiently and accurately. |