Effects of Phase Scintillation on the GNSS Positioning Error During the September 2017 Storm at Svalbard

Abstract

In early September 2017, several space weather events triggered disturbed conditions of the near‐Earth space. The combination of two coronal mass ejection arrivals, associated with an X‐class flare, caused a strong geomagnetic storm on 7 and 8 September, thus inducing diffuse ionospheric phase scintillations on Global Navigation Satellite System (GNSS) signals. This work analyzes the effects and the actual impact of such phase scintillations on transionospheric Global Positioning System (GPS) signals and on related positioning accuracy. The research focuses in particular on high‐latitude GPS L1 data, recorded during a test campaign in Svalbard, Norway. The joint effect of satellites at low elevation and the exposure of ionosphere to the geospace forcing make navigation a critical task for such a challenging environment. Data analysis shows that the performance of carrier smoothing algorithms was affected by the presence of moderate and strong phase scintillation. It is shown in this study that positioning errors double when GPS signals affected by scintillation are used. This work shows that scintillations induce a considerable clustering effect on the smoothed positioning solutions; therefore, a methodology to automatically and autonomously detect the boundaries of the scintillation event is suggested according to such an high‐level effect. The use of software‐defined radio receivers for automatically capturing and processing GNSS data affected by scintillation is an added value to the analysis, as it offers the possibility to implement advanced signal processing techniques and a deeper observation of the impact of scintillations on the signals.

Survey on signal processing for GNSS under ionospheric scintillation: Detection, monitoring, and mitigation

“…The main limiting factor for the use of low‐cost mass‐market GNSS receivers for this purpose (i.e., to avoid high‐cost professional dedicated ISMR with very stable clocks and perfectly known position) is the clock‐induced phase errors. Considering the architecture proposed in Vilà‐Valls, Closas, and Curran (2017a), we show new results for a high‐latitude scintillation event, recorded in September 2017 over Longyearbyen, at the Svalbard Islands, Norway (Linty, Minetto, Dovis, & Spogli, 2018), using a customized receiver developed by the NavSAS group of Politecnico di Torino (Cristodaro et al., 2018). As a low‐cost receiver clock example, we consider a typical temperature‐compensated crystal oscillator (TCXO), for which we measured the clock‐phase‐induced errors.…”

“…Concerning amplitude scintillation, is chosen by many authors (Adewale et al., 2012; Aon, Othman, Ho, & Shaddad, 2015; Dubey, Wahi, Mingkhwan, & Gwal, 2005; Middlestead, 2017; Romero Gaviria, 2015); other works consider scintillation moderate in the range between 0.2 and 0.5 and strong above 0.5 (Jiao, Morton, Taylor, & Pelgrum, 2013a). Concerning phase scintillation, a common value is rad (Dubey et al., 2006; Linty, Minetto, Dovis, & Spogli, 2018). Sometimes, the same authors consider different thresholds depending on the type of study being carried out: 0.15 and 0.26 rad for amplitude and phase scintillation, respectively, to detect events potentially causing a considerable impact on GNSS measurement accuracy and reliability (Jiao, Morton, Taylor, & Pelgrum, 2013b), while 0.12 and 0.1 rad, for studies on the ionosphere irregularity (Jiao, Morton, Taylor, & Pelgrum, 2013a).…”

“…However, much of the improvement in positioning accuracy provided by modern receivers is due to their exploitation of carrier‐phase measurements. As a result, many modern receivers, and most notably high‐precision receivers, are extremely sensitive to ionospheric scintillation (Banville & Langley, 2013; Banville, Langley, Saito, & Yoshihara, 2010; Jacobsen & Dähnn, 2014; Linty, Minetto, Dovis, & Spogli, 2018; Prikryl, Jayachandran, Mushini, & Richardson, 2014).…”

A Controlled-Environment Quality Assessment of Android GNSS Raw Measurements

“…Code measurements are unambiguous but noisy; on the contrary, while carrier-phase measurements are much more precise but inherently ambiguous, and the process to solve for the integer ambiguity is non affordable by mass-market receivers [12]. An intermediate solution is based on the combination of code-and carrier-phase measurements through a process denoted carrier-smoothing filtering [18,19]. Let ρ(t) and Θ(t) be the code and carrier pseudorange, respectively.…”

A Study of SuperDARN Response to Co‐occurring Space Weather Phenomena

“…In recent times the availability of new data sets such as Super Dual Auroral Radar Network (SuperDARN) and GPS Total Electron Content (TEC) has provided excellent opportunities to further analyze the effects and impacts of space weather on HF absorption. TEC data sets were utilized by Linty et al (), Berngardt et al (), and Gonzalez‐Esparza et al () to analyze the impacts of solar flare and CME‐driven space weather phenomena on communication systems. Specifically, the studies used phase scintillation index, differential TEC, and rate of TEC index to characterize the impact of different space weather impacts on ionospheric propagation conditions.…”