Reconstruction of Ionospheric Electron Density Using Lightning-Generated Whistlers Based on Simulation and Observations

Electron density is a fundamental parameter characterizing the ionosphere. Multiple ground-based and space-based detection technologies are applied to detect ionospheric electron density using artificial electromagnetic waves, based on the ionospheric effects of reflection, refraction, incoherent scattering, and doppler shift on radio waves. Lightning-generated whistlers (LGWs) constitute a natural signal with a wide spatiotemporal distribution that can substitute for these artificial transmissions, achieving global ionospheric detection. This paper proposes a method for reconstructing ionospheric electron density profiles by comparing simulated and observed dispersion of LGWs. We develop an LGW propagation model based on the finite-difference time-domain (FDTD) algorithm, where the background electron density is derived from the International Reference Ionosphere (IRI) model. The dispersion of simulated whistlers is compared with satellite observations, and a modification factor is introduced to modify the background electron density based on the relationship between dispersion and electron density. The approach is applied to two events, and the electron density modification effect is assessed with independent data sources. The results show that the errors between the modified electron density and the true value in two events are reduced by 62.81% and 69.29%, respectively, confirming the efficacy of the proposed method.