Analysis Of Electromagnetic Properties Of Time-domain Finite Difference Method For Random Media

Finite-difference time-domain method(FDTD)has attracted the attention of researchers in the field of computational electromagnetic due to its simple mathematical process and easy to get the wide frequency band information of the object.The conventional FDTD will introduce staircasing error in analysing curved objects.Conformal technique and subgridding technique are proposed to reduce the staircasing error.The finite-difference time-domain(FDTD)method is commonly used to evaluate the electromagnetic fields in atmospheric plasma studies.The traditional method analyzes the electromagnetic characteristics of plasma without considering the stochastic plasma electron density.So this paper uses a stochastic FDTD method based on the polynomial chaos expansion(PCE),the method uses Hermite basis function to expanse random variables and then uses the Galerkin method to test the base function,the mean value and variance of the output field are analyzed when the electron density is changed stochasticly.The accuracy depends on the number of the items.The precision grows with the items,but the consumption of memory and time is also higher.This paper analyzes the electromagnetic scattering characteristics of magnetized plasma using the predictor-corrector method.On the basis of this,a stochastic FDTD algorithm with polynomial chaos expansion is introduced.Then using conformal FDTD to analyze the electromagnetic properties of the random magnetized plasma model.And then.analyzes the electromagnetic scattering characteristics of unmagnetized plasma using the Runge-Kutta exponential time differencing(RKETD)FDTD method.Then the electromagnetic scattering characteristics of hypersonic targets are analyzed by conformal FDTD.At last,On the basis of this,a stochastic FDTD algorithm with polynomial chaos expansion is introduced.analyzing the electromagnetic scattering characteristics of hypersonic stochastic medium.