volume | PIER Journals

Abstract

Based on the theory of ionospheric heating, with the self-consistent model in the low ionosphere, the Extremely-Low-Frequency (ELF) and Very-Low-Frequency (VLF) waves generated by modulated beat-wave ionospheric heating are analyzed theoretically. In the consideration of the stratified ionosphere, the magnetic fields generated by the equivalent ELF/VLF dipole source above thesea surfaceare studied by using the quasi-longitudinal approximation method.Taking the high latitude regions as an example, the variations of the electron temperature, the increments of Pedersen and Hall conductivities and the changing of the oscillating current densitywith the modulation frequency in beat-wave heating are numerically discussed. The distribution of the magnetic fields ispresented. It turns out that in high latitude regions, the efficiency of rectangular wave modulated heating ingenerating ELF/VLF wave is higher than that of modulated beat-wave heating, and the order of magnitude of the magnetic fields received above the sea surface is 10^-7 in beat-wave modulation.

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Dr. Hai-Ying Li

Dr. Jie Zhan

Prof. Zhen-Sen Wu

Dr. Pengfei Kong