SAPIWI program has been developed to model atmospherics propagation in the Earth-ionosphere waveguide with non-uniform conductivity

The program makes it possible to model atmospherics propagation as electromagnetic wide-band signal though the natural Earth-ionosphere waveguide with inhomogeneities in 2-D waveguide section orthogonal to the Earth. Mathematical modeling is implemented on the basis of Maxwell equation. Inhomogeneities are set on the basis of ABC and PML principles. The software realizes numerical solution of the model by FD-TD method. A user can describe different models indicating the sampling interval of computational grid, simulation time, absorption region thickness, inhomogeneity region and degree, visualization parameters. The program makes it possible to record the result into a video file.