Study On Electromagnetic Compatibility Of Transmission Line Based On FDTD Method

With the development of electronic science and technology towards high-speed, wideband, high-sensitivity and miniaturization, the transmission lines of power and communication become more and more dense, PCB becomes smaller and the frequency of clock signal becomes higher. Therefore, the phenomenon of signal delay, distortion and crosstalk becomes more and more serious. These problems can be come down to the research of Multiconductor Transmission Lines (MTL). Hence, the theory of MTL plays an important role in analysis and prediction of electromagnetic compatibility (EMC) between equipment and system.Based on finite difference time domain (FDTD) method and the theory of MTL, the transmission line's transient response is analyzed through building model and simulating for MTL. Besides, combining of MATLAB and C++, the software for transient response analysis of multiconductor transmission lines is worked out.Firstly, theoretical Basis of subject research is introduced in this thesis, including basic principle of FDTD, numerical stability, absorbing boundary, Telegraph Equation, calculation of per unit length of parameters and so on. To analyze the simulation result conveniently and visually, this paper makes an introduction of crosstalk between lines based on the lumped parameter model. Then, transient responses of many kinds of MTL under different excitation sources are studied, through derivation of MTL iterative equations using the FDTD method and modeling of MTL. In the practical system, multiconductor transmission lines are often loaded by nonlinear devices, so a further research on multiconductor transmission lines loaded by nonlinear devices is done. In the last of the paper, the software for transient response analysis of multiconductor transmission lines is designed, which helps users obtain the simulation result effectively and provides valuable reference information for engineering design and prediction of EMC.