Authors:G. Miró, S. M. Radicella, B. A. De la Morena, and et al.
The effects of three geomagnetic storms on the ionospheric F region and the influence of the G condition on TEC estimates have been analysed by using ionospheric data from INTA El Arenosillo Atmospheric Sounding Station (37.1N, 353.3E) and GPS TEC measurements obtained at the IGS station of San Fernando (36.5N, 353.8E). The results stress the importance of these perturbations and the need of using edited ionograms.
Authors:V. E. Gherm, N. N. Zernov, S. M. Radicella, and et al.
The propagation model for signal fluctuations on transionospheric radio links previously developed by the authors has been further extended to be capable of describing some new applications e.g. spatial coherency of the field, or the time-correlation properties of level (log-amplitude) and phase fluctuations and their frequency spectra. In particular, the technique has been developed to also generate random time sequences of the level and phase of the field on transionospheric paths of propagation. Spatial coherency is of importance for differential GPS in the assessment of the additional fluctuational errors in rangefinding with respect to a reference GPS station whereas random time series are necessary for modelling the fluctuational Earth-satellite channel of propagation.