Empirical analysis of user position for various conditions using gnss single frequency receiver

Abstract

Global Navigation Satellite System (GNSS) is a satellite-based navigation and spatial positioning system with global coverage. Out of the many satellite navigation systems developed, the best possible in practice is Global Positioning System (GPS) which is composed of a total of 24 satellites (21 operational and 3 backup). The accuracy of GPS can be improved by Satellite Based Augmentation System (SBAS). The Indian SBAS is GAGAN (GPS Aided GEO Augmented Navigation). It supports wide area or regional augmentation using additional satellite broadcast messages. GAGAN is a planned implementation of SBAS by the Indian government. It is a system to improve the accuracy of GNSS receiver by providing reference signals. In this work, experimental data is obtained from JUNO SA single frequency GPS/GAGAN receiver under various conditions such as during morning, afternoon, evening, open-sky, half-sky, heavy canopy and under portico (half open sky). The work is carried out at Department of Electronics & Communication Engineering (ECE), University College of Engineering (UCE), Osmania University (OU), Hyderabad (17.4135° N, 78.5287° E). The user position is obtained separately using standalone GPS and GAGAN. It is observed that the parameters such as Accuracy, PDOP (Positional Dilution Of Precision), HAE (height above ellipsoid), etc. differ under various environmental conditions such as during day/night, open sky/heavy canopy, within closed structures etc.