V.V. Demyanov, V.V. Kiryushkin, D.A. Cherepanov

During geomagnetic storms the strong scintillations of transionospheric UHF radio signal are produced by dispersion of signal on small-scale ionospheric disturbances. The occurrence of such disturbances at the middle latitudes is caused by expansion of auroral oval during a geomagnetic storm. The basic contribution to scintillations of transionospheric UHF radio signal is introduced by perturbations of electronic concentration with sizes of the first Fresnel zone (150-250 m). The phase carrier measurements of GPS signals are the most sensitive to changes of geomagnetic conditions. During the tracking loss of control loop of phase the navigation receiver is switched to a mode of search and capture of the GPS signal. At this time the radionavigation parametres obtained on the navigation signal of corresponding satellite are absent. At this paper the technique of experimental estimation of a possible range of sudden changes of absolute value and speed of a phase carrier increase of GPS navigation satellites signals in the conditions of effect of geomagnetic disturbances is developed. The obtained experimental results are the serious reason to revise more carefully the mechanism of influence of geomagnetic disturbances of the environment on a quality of functioning of global navigation satellite systems (GNSS). The variant of realization of GNSS receiver adaptation to influence of adverse gelio-geophysical factors is offered. In a normal mode the tracking measuring instrument operates only with use the control loop of phase with a narrow band of capture. When the phase and peak scintillations are found out the capture band extends to adapt for the new conditions of navigation signal reception.