Estimation of spatial structure of lower ionosphere with two-dimensional FDTD simulations

We performed a series of FDTD simulations with different types of electron density profiles in the lower ionosphere, and then confirmed characteristics of MF wave propagations in the lower ionosphere. According to sounding rocket experiments, we can only obtain an altitude profile of wave intensity, especially magnetic field intensity, by rocket observations. In this study, therefore, we are going to try to estimate spatial structure in the lower ionosphere by analyzing altitude profiles of magnetic field intensities of waves with various frequencies. Simulation results indicate that spatial structure in the lower ionosphere can be estimated by analyzing altitude profiles of different waves emitted from different wave sources with various frequencies.