Impact of Intense Geomagnetic Storm on NavIC Signals Over Indore

Abstract

Intense geomagnetic storms can have a strong impact on the signals (termed as ionospheric scintillations) emitted by any global navigation satellite system (GNSS). The paper reports the first ever scintillations at Indore region on the NavIC signals due to impact of the intense geomagnetic storm event reported on September 8, 2017 at 01:51 and 13:04 UT. The variation of the planetary indices as well as the DST index which dropped to 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 co-located GNSS receiver showed values ≥0.5 on the disturbed day between 15 and 18 UT. The analysis presented clearly signifies the degradation of carrier-noise measurements of NavIC L5 signal during the same time, which in turn affected the positional accuracy of NavIC, an important consideration for performance.

Systematic study of ionospheric scintillation over the indian low-latitudes during low solar activity conditions

“…It is engineered to provide positional accuracy information not only to the Indian users but also to the users within a 1500 km radius around its boundary, defined by a rectangular grid spanning from 30 o S to 50 o N in latitude to 30 o E to 130 o E in longitude (Mruthyunjaya and Ramasubramanian). The reliability of NavIC in exploring the upper atmosphere has already been demonstrated by (Mehulkumar and Shweta, 2018;Desai and Shweta, 2018;Ayyagari et al, 2020;Chakraborty et al, 2020a;Mukesh et al, 2020;Ravi Kumar et al, 2019;Rethika et al, 2015;Sharat et al, 2017;Chakraborty and Datta, 2021;Ayyagari et al, 2021;Sinha et al, 2019;Prajapati et al, 2021;Chakraborty and Datta, 2020;Ayyagari et al, 2019). The signal intensity and accuracy of NavIC satellites have recently been confirmed by (Sharma et al, 2019), to be reliable and used for ionospheric scintillation studies.…”