A novel ultrawideband FDTD numerical modeling of ground penetrating radar on arbitrary dispersive soils

A novel two-dimensional (2-D) finite-difference time-domain algorithm for modeling ultrawideband pulse propagation in arbitrary dispersive soils is presented. The soil dispersion is modeled by general power law series representation, accounting for multiple higher order dispersive relaxation processes and ohmic losses, and incorporated into the FDTD scheme by using the fractional derivative operators. The dispersive soil parameters are obtained by fitting the reported experimental data. Moreover, dedicated uniaxial perfectly matched layer for matching dispersive media are derived and implemented in combination with the basic time-marching scheme. Examples are given to verify the numerical solution and demonstrate its applications. The proposed technique features a significantly enhanced accuracy in the solution of complex electromagnetic propagation problems typically encountered in geoscience applications.