Impact of Intense Geomagnetic Storm on NavIC Signals Over Indore

TL;DR

This study investigates how an intense geomagnetic storm on September 8, 2017, affected NavIC satellite signals over Indore, revealing significant scintillations and degradation in signal quality impacting navigation accuracy.

Contribution

First analysis of geomagnetic storm effects on NavIC signals at the Indore region, highlighting ionospheric scintillations and their impact on navigation performance.

Findings

S4 index exceeded 0.5 during storm hours

Carrier-to-noise ratio degraded during geomagnetic disturbance

Positional accuracy of NavIC was affected during the storm

Abstract

Intense geomagnetic storms can have a strong impact on the signals (termed ionospheric scintillations) emitted by any global navigation satellite system (GNSS). The paper reports the first studies of scintillations at the Indore region on the NavIC signals due to the impact of the intense geomagnetic storm event reported on September 8, 2017, at 0151 and 1304 UT. The variation of the planetary indices as well as the DST index which dropped to a value of -124 nT on September 8, 2017, indicates the occurrence of an intense geomagnetic storm on September 8, 2017. The observations presented are carried out at Indore, which is located at the equatorial anomaly crest. The S4 index measurements of colocated GNSS receiver showed values of 0.5 or above on the disturbed day between 15 and 18 UT. The analysis presented clearly signifies the degradation of the carrier to noise measurements of the NavIC L5 signal during the same time, which in turn affected the positional accuracy of NavIC, an important consideration for performance.