Positioning and Signal Strength Analysis of IRNSS and GPS Receiver in Plain Terrain along with Foliage Loss

Abstract

Navigation systems such as Global Positioning System (GPS) play a significant role in determining the user position. Similar to GPS, Indian Regional Navigation Satellite System (IRNSS) is a navigation system indigenously developed by India to meet the country's needs. Presently, six satellites are in orbit -three in inclined geosynchronous orbit and three in geostationary earth orbit. It is essential to evaluate and upgrade the performance of IRNSS continuously for various applications. One such assignment to characterize the performance of IRNSS is mapping of the Jain University global campus geographical area in Bengaluru. The area for mapping includes a terrain with different features such as plain fields, vegetation fields, power distribution substation, dense trees and a terrain with variation in altitude. The purpose of this study is to analyse the performance of both IRNSS and GPS with respect to carrier-to-noise ratio, altitude variation, satellite visibility and GDOP, and the corresponding observations are recorded and plotted with available maps.

Study of Azimuth Angle and Elevation Angle Variations of IRNSS/NavIC Signals

“…Ephemeris data is unique for every satellite. All the GNSS systems, GPS of The United States, GLONASS of Russia, GALILEO of Europe and BEIDOU of China [7], additionally there are regional navigation systems which are QZSS of Japan and India's very own IRNSS-use extremely accurate Rubidium or Cesium stable atomic clocks, with error probability of 1 second in every hundred million years, while receivers back on earth have crystal oscillators for providing time, these are chosen for economic reasons and are not synchronized with on board atomic clocks of the navigational satellites. This asynchronization reflects in calculated position and range.…”