Application of FDTD Method in VLF Propagation Research

Electromagnetic waves in the very low frequency (3k-30kHz, VLF) band have the characteristics of low attenuation and good penetration performance during transmission. At the same time, the amplitude and phase of very low frequency electromagnetic waves are relatively stable. These characteristics have made very low frequency electromagnetic waves widely used in fields such as long-distance communication, lightning remote sensing, and global climate observation. In order to accurately simulate the propagation characteristics of VLF electromagnetic waves in the ionosphere, the FDTD method is currently mainly used for modeling and analysis. This article first introduces the historical evolution of FDTD method in studying VLF propagation, analyzes the established FDTD model, and finally provides a summary of certain reference values.