Ionospheric scintillations computation using real-time GPS observations

Abstract

The following paper presents the results of quasi-real-time determination of the values of phase scintillations indices at the period of ionospheric disturbances that occurred as a consequence of the Sun flares observed on March 7 and 9, 2012. Double-frequency observations with 1-second measurement interval from the EPN (EUREF Permanent Network) network sites located at high latitudes were used for the analysis. To determine the phase scintillations it is necessary to apply data filtering in order to separate the trend of low frequencies (e.g. satellite motion) from high frequency oscillations (e.g. scintillations). Elimination of low frequency components of the signal using moving average was proposed in the research. This approach was conditioned by the necessity to apply an optimum method of filtering for quasi-real-time calculations. The scintillation parameters were calculated by means of three different algorithms and the results were compared. Additionally, relations between changes of the parameters and the ROTI index, describing the temporal changes of TEC, and the decrease of positioning accuracy at the analyzed sites were searched.