ELF Attenuation Factor Derived from Distance Dependence of Radio Wave Amplitude Propagating from an Artificial Source

Abstract

The distance dependence was used of the artificial extremely low frequency (ELF) radio signal measured in the Atlantic Ocean for establishing the attenuation rate at a particular frequency. We demonstrate that value obtained is in accord with the literature data, as well as with the model based on the Schumann resonance measurements. Deviations do not exceed the standard inaccuracy conditioned by the finite signal to noise ratio. The attenuation factor thus obtained might be used for testing models of the Earth - ionosphere cavity. Absolute calibrations of measurements provided the effective current moment of the field source.