A parallel optimization 3D numerical ray-tracing method for the fast and accurate simulation of disturbed oblique ionogram

Abstract

A novel parallel optimization 3D numerical ray-tracing method is proposed in this paper. The method takes the geomagnetic field and the horizontal in-homogeneity of the ionosphere into account. It works in both O-mode and X-mode. High-frequency radiowaves and oblique ionograms are simulated by the method under three different plasma density models with travelling ionospheric disturbances and small-scale irregularities and without them. Both the parallel optimization algorithm (MultiStart) and the parallel traversal algorithm are used during the simulation, which allows multiple rays to be traced simultaneously to shorten the simulation time. The simulation results show the proposed 3D numerical ray-tracing method can sensitively and accurately capture the changes that geomagnetic field, travelling ionospheric disturbances, and small-scale irregularities bring to the high-frequency radiowaves and the oblique ionograms. It is a useful tool for restoring different oblique ionogram characteristics under various parameters on the plasma density models.