Analysis of Amplitude Scintillation and Positioning Error of IRNSS/GPS/SBAS Receiver for Heavy Rainy Days

Abstract

Indian Regional Navigation Satellite System (IRNSS) was developed for providing positioning, velocity and timing information to Indian users within the error of 10 m. Amplitude scintillation is the rapid fluctuations in amplitude of navigation signal due to small scale irregularities in electron density presents in ionosphere. Strong scintillation can degrade the accuracy of navigation system and generate the errors in precise positioning services. S4 index is the statistical measurement of amplitude scintillation which reflects scintillation event. The characteristics of amplitude scintillation on IRNSS/SBAS/GPS receiver with all seven satellites during heavy rainy days at the low altitude station IITRAM, Ahmedabad are investigated. The raw data are collected from the IRNSS/GPS/SBAS receiver with L1, L5 and S band at the Ahmedabad city with average altitude of 53 m in Gujarat. Here, real time monitoring system for amplitude scintillation and positioning error is designed for all three bands. S4 values for three bands are calculated and analyzed to define the scintillation event for the period of 14 days. The position errors of heavy rainy days are also found. This study also focuses on time duration over which the carrier to noise ratio acquires zero value, effect of elevation angle of satellite on carrier to noise ratio and ionospheric delay. We found that L1 band suffers more from scintillation compare to L5 and S band. Day to day investigation of amplitude scintillation is carried out here. The results of this investigation would be utilized for understanding of amplitude scintillation effect during rainy weather condition in low altitude station.

KEYWORDS:

• Amplitude scintillation
• Carrier to noise ratio
• GPS
• Ionospheric delay
• IRNSS/NavIC
• Positioning error
• PVT
• S4 index

Supplemental data

Supplemental data for this article can be accessed at https://doi.org/10.1080/03772063.2021.1886608

Additional information

Notes on contributors

Mitchell Prajapati

Mitchell S. Prajapati received the Bachelor of Engineering degree in electronics and communication from Saurashtra University in 2005. She received master's degree with specialization in communication system engineering from Gujarat University in 2009. Presently, she is pursuing PhD in Electrical Engineering from the Institute of Infrastructure Technology Research and Management at Ahmedabad. Her research area is in the field of satellite navigation systems. She has a teaching experience of fifteen years. Presently she is working as a lecturer in Department of Electronics and Communication Engineering at Government Polytechnic, Vadnagar.

Abhishek Rawat

Abhishek Rawat received his Bachelor of Engineering in electronics and communication engineering (2001), Master of Technology in microwave and MM (2006) and PhD in smart antenna arrays (2012). He has worked as assistant professor in the Department of Electronics and Communication Engineering, at Samrat Ashok Technological Institute, Vidisha, Madhya Pradesh, India. Currently, he is associated with Institute of Infrastructure Technology Research and Management (IITRAM), (A deemed University under the Government of Gujarat) Ahmedabad, Gujarat, India as assistant professor in Electrical Engineering Department. He received young scientist award at 2007 by Madhya Pradesh Council of Science and Technology (MPCOST), Bhopal, MP. Dr Rawat, as senior member IEEE, has published more than 70 articles in international journals, books, book chapters, national and international conference proceedings. He has four published Indian patents and is currently involved in the field trials of the Indian Regional Navigation Satellite System (IRNSS) receiver of Space Application, Center (SAC), Indian Space Research Organization (ISRO) as institute coordinator. IITRAM is also associated with project e-Yantra (A project of Indian Institute of Technology, Mumbai under the MHRD, Government of India), which is also handled by him. He is also working as Co-coordinator of Design Lab at IITRAM and reviewed many international journal papers. One research project “Smart Antenna Design” was also conducted during 2009–2012 under the MPCOST, Bhopal, India. His research interests include satellite navigation systems, satellite communications, advanced communication systems, antenna design, cognitive robotics and peripheral security etc.Email: [email protected]

Divyash Kumbhani

Divyash Kumbhani is currently pursuing BTech in the Department of Electrical Engineering of Institute of Infrastructure Technology Research and Management. He completed academic research projects in satellite communication and biomedical signal processing domain. He has experience of programming, data analysis, machine learning, deep learning and healthcare signal processing. Email: [email protected]