A Study of Effects of Ionospheric Scintillation Intensity Using Gps Data at Low Latitudes

Abstract

Low latitude areas are highly exposed to the effects of ionospheric scintillations caused by the activities in the sun’s corona. Ionospheric scintillation occurs when there are rapid deviations in the signal amplitude or phase frequency as radio signals travel through areas of non-uniformity in the ionosphere. These changes cause adverse effects on Global Navigation and Satellite Systems (GNSS) by producing propagation impairment hence disturbing the satellite systems accuracy in positioning. When scintillations are stronger, satellite receivers can lose lock posing threats to GNSS applications and positioning. Scintillation effects worsen during solar maximum. The receiver-satellite geometry is poorly messed up when the effects of scintillations are higher. Due to the adverse effects posed by irregularities in the ionosphere, there is need to carry out research to study the extent to which scintillation effects can affect navigation tools and propose solutions to improving precision on positioning as well as receiver satellite geometry. This research work presents a detailed study of occurrence of scintillations in the region of Darwin, Australia, at latitude 12.4637° S, a low latitude area. Ionospheric data for Darwin from sws.bom.gov.au/aims are used to analyze the extent of scintillations for the period ranging between January 2020 and April 2021. Amplitude scintillation index and phase scintillation index are used to plot graphs using the gnuplot. The results from the graph show that scintillation is prevalent throughout the period of study, an indication that radio frequency signals passing through the ionosphere is affected adversely. Being a low latitude area, GPS stations located in this place, will need to be monitored for scintillation. Ground based GPS data receivers can be positions at angles that lower the receiver distance from the space satellites. Radio signals with scintillations will have to be corrected before they can give a clear signal for communication.