Numerical Stability Analysis Of TM Wave Transmission Based On FDTD Method

In recent years, with the constant improvement in computer performance and the development of numerical theory, considerable progress has been achieved in computational electromagnetics. Among the informed methods, the Finite-Difference Time-Domain (FDTD) method has gained more and more attention and applications for its outstanding advantages.This paper firstly introduces the characteristics and applications of computational electromagnetic and FDTD method, and illustrates the feasibility of using FDTD for general electromagnetic simulation. Secondly, this paper gives a brief introduction to the basic principle of FDTD method, including the establishment and derivation of the basic equations, the numerical stability, the numerical dispersion and the absorbing boundary conditions etc. And the evaluation of the value of numerical dispersion caused by different space steps is carried out through simulation.Combined with the basic principles of FDTD method, this paper focus on constructing the program flow chart for simulation using FDTD method and carrying out the simulation of TM wave transmission in two-dimensional space using matlab 7.0 based on the reasonable excitation source choice and the absorbing boundary conditions set. The simulation animation vividly demonstrates the impact of selecting different time steps and space steps on the numerical stability. Through the comparative analysis of the simulation results, suggestions on how to choose the value of time steps and space steps are put forward. Furthermore, this paper summarizes the concrete steps for simulation using FDTD method.At last, the future plan about solving the specific problems in the electromagnetic compatibility field using FDTD method is presented.