Abstract. The analysis of errors in the
determination of electron density in the daytime ionosphere of Venus based on
the results of radio occultation and an assessment of the prospects for
obtaining more accurate information about the properties of its ionosphere from
the data of completed and planned missions are presented. The study was
performed on the basis of the data of the Venus-9,-10,-15,-16 satellites and
the simulation of the occultation experiment. According to the radio occultation experiments of completed missions,
the vF2, vF1, vE, vD regions are identified in the daytime ionosphere of Venus,
indicating the stratified structure of the ionosphere due to prevailing
physical processes that are analogous to the processes in the terrestrial
ionosphere layers F2, F1, E, D. Electron density calculations are based on the
integration of data distorted by broadband noise. The simulation of the
experiment showed that the error in determining the electron density in
different regions of the ionosphere is different. The main source of error
in the method of radio occultation is interplanetary plasma on
the radio communication path if its influence on the parameters of the radio
wave significantly exceeds the fluctuations in the amplitude, phase and
frequency of the radio wave caused by the limited stability of the equipment
and the low energy potential of the radio link. It is established that in the
region of vD there will always be a maximum effect of factors that impair the
reliability of the information on the ionosphere. To study the processes
responsible for dynamic changes in the atmosphere-ionosphere system, it is
necessary to increase the energy potential of the radio link in the planned
mission of Venera-D. As a result, improved methods of data analysis will allow
obtaining new information about Venus with good accuracy.
Keywords: radio wave propagation,
occultation of ionosphere, fluctuations in frequency and power of radio waves.
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