Annals of Geophysics, vol.69, 2026 (SCI-Expanded, Scopus)
IONOLAB-RAY is a modular ray-tracing toolbox that models electromagnetic wave propagation through a realistic, time-varying ionosphere represented by a three-dimensional voxel-based grid. Within each voxel, refractive indices are computed from the full Appleton-Hartree formulation, accounting for anisotropy, magnetic field effects, and collisions. The physical parameters of the ionosphere are derived from background ionospheric model, which can be assimilated with Total Electron Content (TEC) data, allowing for the near real-time updating of the statistical model to reflect current ionospheric conditions. The system simulates both ordinary and extraordinary propagation modes under varying geophysical conditions. Designed for global and near real-time operation, IONOLAB-RAY can be executed for any position on Earth and for varying ionospheric states. Its user-friendly interface supports multiple-run simulations, allowing users to analyze wave propagation under different scenarios and explore the influence of input parameters such as signal frequency, elevation, and azimuth angle. For each computed ray path, the toolbox determines key physical parameters – attenuation, phase and group velocity, and total propagation delay – and generates both virtual and real-height ionograms. Real-height ionograms, derived from actual ray trajectories, provide essential insights into true reflection altitudes and ionospheric structure. Through its flexibility, physical accuracy, and operational efficiency, IONOLAB-RAY serves as a powerful framework for ionospheric modeling, propagation analysis, and space environment studies.