Propagation Modeling Over Irregular Terrain by the Improved Two-Way Parabolic Equation Method

The two-way split-step parabolic equation (2W-SSPE) method is improved to be able to model both forward- and backward-waves propagation over irregular perfectly electrical conducting (PEC) surfaces and irregular lossy surfaces with impedance boundary conditions (IBC). The discrete mixed Fourier transform (DMFT) is applied in both forward- and backward- direction to deal with IBC, and the boundary shift (BS) method is used to dispose of the irregular terrain effects. Numerical results obtained by the improved 2W-SSPE algorithm for several typical scenarios with different ground types are compared with those got by the previous 2W-SSPE method and the one-way parabolic equation method.