Effect of ionospheric irregularities on GPS signals during declining phase of solar cycle 23 at Bhopal

Frontiers of Physics and Plasma Science

Mansoori, Azad A.^1 ; Purohit, P.K.^2

Department of Electronics, Barkatullah University, Bhopal, MP

462026, India^1

National Institute of Technical Teachers' Training and Research, Bhopal MP

462002, India^2

关键词: Amplitude scintillation;    Correlation analysis;    Different sizes;    Equatorial anomaly;    Equatorial regions;    Geomagnetic conditions;    Geomagnetic storm;    Ionospheric irregularities;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/836/1/012043/pdf
DOI  :  10.1088/1742-6596/836/1/012043

来源: IOP

【 摘 要 】

The present investigation is dedicated to the evaluation of GPS performance under disturbed geomagnetic conditions at the equatorial region. When GPS signals encounter the ionospheric irregularities of different size developed during high geomagnetic or solar activity, they undergo rapid changes in their phase and amplitude, known as scintillations. We have studied the occurrence characteristics of scintillation events during geomagnetic storms of different intensity at the crest of equatorial anomaly station Bhopal (23.2N, 77.6E). To accomplish this study we have used two data sets: Disturbed Storm Time (Dst) index and Amplitude Scintillation (S4) index. The geomagnetic storm activity is characterized by the Dst index and the evaluation of GPS performance during disturbed geomagnetic condition is realized through S4 index. We have selected thirty one geomagnetic storms that occurred during the year 2004 and 2005. We then classified these geomagnetic storms and scintillation events into weak, moderate and intense and weak, moderate and strong according to Dst index and S4 index respectively. During all the storm events we observed a good number of scintillation events. We then performed the correlation analysis between the Dst index and S4 index, to find out the impact of storm intensity on the occurrence of scintillation events.