Experimental study of meteorological parameters variation using HF-signal during solar proton events

This paper presents the statistical studies of the signal level variation processes which give some information about meteorological processes in the troposphere. Refractive index, which plays a significant role in radiowave propagation relates to the main meteorological parameters such as temperature, pressure and vapor pressure. To solve this problem, an experimental radio link from the telecommunication satellite was constructed, where more than 20 flare events are analyzed. After three days the received signal return to the normal, nonflare state. This fading can be connected to the phenomena of the interference between few signals originating at different sources like tropospheric inhomogeneouses and the satellite. These inhomogeneouses are linked to small scale fluctuation of refractive index. When analyzing time delays between beginnings of the solar flare and the flare distribution is possible to assume that solar flare products influencing on tropospheric parameters may be ultraviolet or X-rays or high energy solar photons. The first two appear in the Earth´s atmosphere in 8-9 minutes after the flare begins, whereas the latter appears near Earth´s space in 1-2 hours after the solar flare beginning. So, the tropospheric inhomogeneouses linked to tropospheric inhomogeneities can play a significant role in UHF (ultra-high frequency) radiowaves propagation. Thus the experimental result concludes that tropospheric inhomogeneouses disappear from 48 to 72 hours after the beginning of the solar flare where the high energy solar proton density comes back to the previous level.