Dynamic Demonstration Of Object Scattering Data On FDTD Algorithm

Electromagnetic analysis of target scattering has been widely used in military and civilian.It can analyze and process many specific conditions about target object in near-and far-field,which makes very important effects for major research, such as radar technology, physicaldetection and so on. This paper presents some applications about traditional finite-differenttime-domain (FDTD) method in target scattering analysis and introduces alternative directionimplicit-(ADI-) FDTD algorithm to deal with relevant problems in unconditional stability.According to Maxwell’s equations, numerical discrete differential treatments are handled inspatial and time domain, and Yee’s cells are constructed as the basic cell to simulateelectromagnetic field. The paper is considered the stability condition and numerical dispersion ofthe FDTD and discusses about the excitation setting in detail. As the limited computing region incomputer, electromagnetic waves can realize to prorogate in free space when absorbingboundary condition is given. Therefore, we analyze about Engquist-Majda absorbing boundarycondition, Mur’s absorbing boundary and coordinate-stretched perfectly matched layer in detail.For the far-field situation of target scattering, the fundamental theory about extrapolation fromnear-field to far-field is further explained, and then computing results about far-field can beobtained.ADI-FDTD and its matrix form have been discussed to simulate the3D-scattering examplesabout the different target structure. Visual programming software has been applied to dynamicdisplay which indicates electromagnetic waves propogating properties in time domain.