A Comparative Analysis of Ionospheric Effects on Indian Regional Navigation Satellite System (IRNSS) Signals at Low Latitude Region, Surat, India Using GDF and Nakagami-m Distribution

Abstract

Indian regional navigation satellite system (IRNSS) is our own navigation system designed to provide various navigational and timing services in Indian region. The present paper discusses ionospheric scintillation effects on IRNSS signals in Surat, (21.16°N, 72.68°E; Geomagnetic 12.90°N, 147.35°E) India, a low latitude station. Ionospheric scintillations are one of the major sources of errors in satellite communication which may results in loss of lock of with particular satellite causing discontinuity of satellite services. Ionospheric Scintillation is experienced by satellite signals when propagating through various layers of atmosphere in terms of random fluctuations in amplitude and phase of signals, and also causes ionospheric delay. The present analysis is done on 3rd October 2015 data for calculation of Ionospheric scintillation measuring parameters like total electron content (TEC) and Vertical TEC using IRNSS data. During this time only four satellites were launched from PRN 1 to 4 by Indian space research organization (ISRO). The comparative behavioral analysis of TEC variation is done using Gaussian distribution function (GDF) and Nakagami m (NGK) model distribution. The carrier to noise (C/N) ratio and elevation angle variations for satellite PRN numbers from 1 through 4 is also carried out. It is seen from comparative analysis that total electron content variations in this geographical location are more following the Nakagami distribution as compared with GDF. The results can be utilized further for developing model for analyzing variations in TEC in this region.