How the Ionosphere Affects Positioning Solution Using Terrestrial and Satellite Navigation Systems?

Abstract

The Earth’s ionosphere, a dispersive medium, is an atmospheric layer that lies typically between 50 and 1,000 km of altitude. The physical parameters of ionosphere have a direct influence on propagation delay (Satellite Navigation Systems – SNS) and on a radio waves propagation (Terrestrial Radionavigation Systems – TRNS), that both cause significant user’s position error and additionally in the case of TRNS the lack of the position sometimes. The most frequently used solutions to this problem, as the dual–frequency receivers which permit the calculation of ionosphere-free pseudorange, model of the ionosphere with eight coefficients transmitted in navigation message or differential mode with pseudorange corrections (SNS) and different corrections to the measurements as SWC and ASF in Loran C system (TRNS) are described in this paper. The detailed relations and equations concerning ionospheric delay are presented also.