ABSTRACT
In recent decades demand has increased for mobile-satellite systems designed to provide global radio coverage and servicing using constellations of low-Earth-orbit (LEO) and medium-Earthorbit (MEO) satellites, which have been intensively utilized in the operation of global positioning systems (GPS), in particular. Under these conditions, signals are typically received at high elevation angles by a moving or stationary vehicle placed at ground surface. Only ionospheric-layered structures with irregularities developed within these layers can affect the propagate radio signals with information through ionospheric radio channels. Unlike land communication channels, ionospheric channels are highly statistical in nature, because coverage across hundreds of kilometers has to be considered in terms of the large variations encountered in wide areas, caused by a broad spectrum of ionospheric geophysical features and processes.
