Features of generation and propagation of the extremely low frequency waves excited in the ionosphere under the powerful HF radioemission influence

The experimental results of the extremely low frequency emission characteristics excited in the outer ionosphere under the ionospheric plasma heating by high-latitude EISCAT facility are presented. The experiments have been conducted in the period of 2006-2010 yr. using two main schemes of extremely low frequency generation including the impact of the heating facility amplitude modulated emission and two unmodulated pump waves with the frequency detuning. In-situ measurements of the plasma wave disturbances were performed at the outer ionosphere heights using on-board equipment of DEMETER microsatellite. In work the spatial, amplitude and spectral characteristics of the generated extremely low frequency emissions are determined. It is shown that the characteristic size of the extremely low frequency emission is about 400-600 km along the trajectory of the DEMETER microsatellite. The registration area spatial position is determined by both the applied generation scheme and the background plasma density distribution. The extremely low frequency emission electric field strength at the Earth’s outer ionosphere heights is 50-330 μV/m.