Impact of ionospheric scintillation on GNSS receiver tracking performance over Latin America: Introducing the concept of tracking jitter variance maps

摘要

Scintillations are rapid fluctuations in the phase and amplitude of transionospheric radio signals caused by small-scale ionospheric plasma density irregularities. In the case of Global Navigation Satellite System (GNSS) receivers, scintillations can cause cycle slips, degrade the positioning accuracy and when severe enough can even lead to complete loss of signal lock. This study presents for the first time an assessment of GNSS receiver signal tracking performance under scintillating conditions, by the analysis of receiver phase lock loop (PLL) jitter variance maps. These maps can potentially assist users when faced with such conditions; a potential application envisaged for these maps would be in the form of a tool to provide users with information about “current (or expected, if some sort of prediction can be developed in follow on research) tracking conditions” under scintillation; another possibility would be to use the technique described by Aquino et al. (2009) to mitigate against the effects of ionospheric scintillation. In this paper these maps were constructed for scintillation events that were observed in the field during 9–11 March 2011 over Presidente Prudente (22.1°S, 51.4°W, dip latitude ∼12.3°S) in Brazil, a location close to the Equatorial Ionisation Anomaly (EIA) crest in Latin America. Results show that the jitter variances estimated for all the simultaneously observed satellite-to-receiver links during the premidnight hours on 9 and 11 March 2011 increase during the enhanced scintillation levels, indicating the likelihood for cycle slips, loss of signal lock, and degraded accuracy in the observations.