Traveling ionospheric disturbances generated due to periodic plasma heating by high-power high-frequency radiation

The results of observations of variations in the Doppler-frequency shift of electromagnetic radiation of decameter waves reflected from the ionosphere during the plasma modification by highpower radio-frequency radiation from the "Sura" facility and in reference days are presented. The distance from the facility to the diagnostic tools (Doppler radar) was about 1000 km. The traveling ionospheric disturbances corresponding to a delay time of about 50 min with respect to the time of switching high-power periodic radiation and a propagation velocity of 300-400 m/s were observed. The relative amplitude of the electron-density perturbations was 1-4 %, while their oscillation period amounted to tens of minutes. The parameters of the traveling ionospheric disturbances significantly depended on the "Sura" facility radiation mode.