General polynomial chaos‐based expansion finite‐difference time‐domain method for analysing electromagnetic wave propagation in random dispersive media

Abstract

A new approach for using polynomial chaos-based expansion finite-difference time-domain (PCE-FDTD) is presented to calculate the uncertainty of electromagnetic wave propagation in dispersive materials. Based on the bilinear transform method, this approach performs polynomial expansion on random electromagnetic fields by PCE-FDTD method. The proposed algorithm has a simple formulation and is very easy to extend to isotropic dispersive material. It has a general form for different types of random dispersive materials and can efficiently calculate the mean value and the SD of electromagnetic field components in a single run. Two examples of different dispersive media with two random variables are listed to show the generality of the algorithm, and a radar cross-section of a perfectly conducting cylinder coated by a layer of random plasma is illustrated as an example to show the practicability of the approach. The results are validated by comparing it with the Monte Carlo method.