The Influence of the Lower Ionospheric Disturbances on the Operating Conditions of Navigation Satellite Systems

The study of the impact of ionospheric disturbances on the conditions of functioning of satellite communication and navigation systems and the development of methods to reduce this effect requires the development of methods for evaluating the parameters of ionospheric disturbances and their spatial and temporal distribution. Studies show that electron concentration disturbances, which can have a significant impact on the functioning of transionospheric radio channels, can occur both in the upper and lower ionosphere. At the same time, the methods of studying the dynamics of ionospheric disturbances in the lower ionosphere are not enough developed, and the interrelation of the lower and upper perturbations of the ionosphere is insufficiently studied. The aim of the work is an experimental study of disturbances of the upper and lower ionosphere in order to clarify the mechanisms of their relationship and study the spatiotemporal distribution of mid-latitude disturbances. The results obtained show that the contribution of the electron density disturbances in the D region to the total electron content of the ionosphere can be significant and considerably depends on the type of heliogeophysical processes