Based On The Fdtd Method For Non-uniform Grid And Conformal Grid Technology,

With the development of high-performance computers, computational electromagnetism has been made a great progress in recent years. Among all the methods, the Finite-Difference Time-Domain (FDTD) method attracts more and more attention because of its features, and some FDTD-based simulation softwares have also been developed.The main works of this thesis are researches on the gradual non-uniform FDTD mesh generation technology, mesh auto-dissecting technology, grid conformal techniques. Concrete formulae of non-uniform FDTD algorithm are deduced. Data structures and classes of simulation modules and interface connecting kernel modules with input simulation interface and data posterior management are developed. Simulation project integration of function modules is complied, and an integrated all-purpose simulation software (GCEM Ver1.0) is accomplished.The main results are as follows:In Chapter 1, we introduce the background and summarize the merits and applications of the FDTD method. Then we introduce some popular FDTD softwares and show the meaning of this thesis.In Chapter 2, we present the principle of the algorithm, including its three key factors: the difference scheme, the stability condition and the Absorbing Boundary Condition (ABC).In Chapter 3, we elaborate the gradual non-uniform mesh technology and mesh auto-dissecting algorithm used in this program.In Chapter 4, we present PEC and dielectric conformal techniques and elaborate the conformal techniques used in this program.In Chapter 5, we introduce the design principle and flow chart of the simulation software and elaborate each function object module in the FDTD computation module. Then we integrate the three function modules, pre-management module, FDTD computation module and post-management module, into the simulation project and achieve the first edition of this simulation software (GCEM Ver1.0). Finally we simulate transmission problem in uniform medium transmission line, and explain the use of the software.In Chapter 6, the whole work of this thesis is concluded.