Recent Advances in Numerical Simulation of Propagation of EM Waves in the Earth's Ionosphere

Abstract

EM wave propagation in the magnetoactive terrestrial ionosphere was investigated by numerical methods, and associated software was developed. Two principal functions were realized: ray tracing and ionogram synthesis. For the first time, reference-standard models, including the International Reference Ionosphere (IRI) 2012, World Magnetic Model 2010, and World Geodetic System 1984, have been globally implemented for every component of the propagation medium, and fully manipulatable 3-D visualization was enabled in a study utilizing the bicharacteristic method. An assimilation model of the ionosphere was also used along with IRI. The focus was on the unveiling of multiskip long-range propagation effects. Effective numerical algorithms for solving the bicharacteristic system that allow rapid insight into an extremely large-scale EM problem and enable quasi-real-time operation were discussed. The simulation in the presence of abnormal locally increased or decreased electron density in the ionosphere of natural or artificial occurrence was considered. Experimental ionograms obtained by an ionosonde were compared to numerically synthesized ones.