Backscattering of radio waves by artificial irregularities of plasma in the lower ionosphere

Abstract

We present the results of the experiments on studying the mechanism of the appearance of artificial disturbances at the altitudes of the E region when a high-power wave is reflected in the ionospheric F layer. The ionosphere was disturbed for a few minutes by a high-power o-mode radio wave radiated by the transmitters of the "Sura" facility at frequencies 4.3 or 4.7 MHz. The disturbed region was sounded using a partial-reflection setup at a frequency of 2.95 MHz. The influence of the artificial disturbance on the probing signal at altitudes lower than the height of reflection of a high-power wave at 40-100 km was recorded on the basis of measurements of the altitude-time characteristics of the probing-signal amplitude. Possible mechanisms of the influence of the disturbance in the lower ionosphere on the probing radio waves are discussed.