volume | PIER Journals

Abstract

As ionosphere is one of the most prominent sources of error, ionospheric TEC and scintillation studies are necessary for improving the performance of a navigation system. In this paper, the behavior of the correlation coefficient (ρ) between Rate of TEC Index (ROTI) and amplitude scintillation index (S₄) over low latitude station Hyderabad (Latitude: 17.44° (deg.) N, Longitude: 78.74° (deg.) E) for different seasons is analyzed. Also, the analysis is extended for nearly same longitude stations like Trivandrum, Bangalore, Bhopal, Delhi and Shimla for the higher values of total K_p index for 60 days (most disturbed 5 days per month). For Trivandrum (lowest latitude station), it is observed that both S₄ and ROTI are high as compared to Bangalore, Bhopal, Delhi, and Shimla. It is found that there is a good correlation between the temporal variations of ROTI with S₄ after post sunset hours. The confidence intervals for computed correlation coefficients at 95% confidence level are also given.

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Dr. Neelakantham Alivelu Manga

Dr. Kuruva Lakshmanna

Professor Achanta Dattatreya Sarma

Dr. Tarun K. Pant