The application of PE in the propagation of VLF wave in earth-ionosphere waveguide

This paper presents a new method for the calculation of VLF propagation in the earth-ionosphere waveguide using the parabolic equation (PE) method. The PE is commonly used to solve the problem of radio wave propagation within atmospheric ducts at high frequencies. The required initial field, refractive index, and boundary conditions for the calculation of the PE under the environment of the earth ionosphere waveguide are studied. Further, the path loss of VLF after long-distance propagation is simulated. Compared with the waveguide mode theory as well as other commonly used methods for the propagation calculation of VLF, the presented method is simpler.