Eigenmode Prediction of the Schumann Resonances

The electromagnetic simulation of the Earth eigenfrequencies is covered, the so-called Schumann resonances. Comparisons to analytical and also measured results are presented, validating the approach. Similar numerical evaluations performed in time domain (finite-difference time-domain) and frequency domain (finite-element method) are also used for comparisons. The eigenmode resonances hereby computed do not need a source of excitation, unlike time-domain codes. A simple Earth model is evaluated (two concentric lossless metallic spheres), as well as one model with a ten-layer atmosphere finite conductivity profile, and also an oblate spheroid geometry. To the knowledge of the author, this is the first reported electromagnetic simulation of the earth Schumann eigenomodes, considering it a closed structure without need for excitation. The eigenmode analysis allows a simple and effective resonance frequency of not only the Earth but also other planets. Comparisons to available experimental data prove the effectiveness of the analysis.