D. S. Kotik

Experimental study of low-frequency emission from a mobile ionospheric source

The results of an investigation of VLF radiation generated by a mobile ionospheric source are presented. Radiation at frequency F appears due to the operation of two powerful HF transmitters at frequencies f and f±F fed to two space-separated antennas. The intensity of the signals received at the ground depends on the location of the source with respect to the receiving point and is determined by the sign and value of the frequency shift F. The proposed model of the phenomena satisfactorily explains the experimental results.

RADIATION OF SUPERLUMINAL IRREGULARITIES ARTIFICIALLY CREATED IN THE LOWER IONOSPHERE

AbstractWe present the results of numerical simulation and physical experiments to verify the possibility of generating a virtual superluminal VLF source by HF ionospheric heating with a scanning beam.The detection of VLF emission was carried out for the source created in two ways:- by scanning the HF beam in opposite directions with different velocities and- by amplitude modulation of a stationary HF beam. The amplitude-frequency characteristics of signals obtained in the experiments show the possibility of radiation pattern control of the VLF emission excited by a scanning HF beam.

Vavilov-Čerenkov and Doppler effects from a superluminal radio-beam spot in the lower ionosphere

We present the results of experimental and numerical studies of the phenomenon of Vavilov-Čerenkov radiation by a superluminal radio-beam spot. We propose a technique aimed at experimental detection of normal and anomalous Doppler effects using the VHF “Sura” facility and the UTR-3 transmitter.