  This work devotes to investigations of solar corona and solar wind plasma by
the method of radio probing with using of very long baseline interferometry
(VLBI). We performed the theoretical calculation of power spectrum of
interferometric response to radio source emission, passed through the turbulent
medium. Data of theoretical analysis are compared with results of international
VLBI experiments on investigations of solar wind plasma. The observations were
realized in 1998, 1999, 2000 with participation of radio telescopes, included
at Low Frequency VLBI Network (LFVN): Bear Lakes (RT-64, Russia), Puschino
(RT-22, Russia), Urumqi (RT-25, China), Noto (RT-32, Italy), Shanghai (RT-25,
China) and others. Preprocessing was carried out with using of S2 correlator at
Penticton (Canada). Post processing of experimental data was performed at RRI
(Russia) and was aimed to obtain value of solar wind velocity and index of
spatial spectrum of electron density fluctuations.
