Analysis for Influence and Geometry of GPS/Galileo System

Lee, Jae-One

Journal of Navigation and Port Research 2005;29(8):763-770.
Published online October 31, 2005.

GPS/Galileo 시스템의 기하구조 및 영향 분석

이재원

Analysis for Influence and Geometry of GPS/Galileo System

Jae-One Lee

Abstract

Global Navigation Satellite System(GNSS) has become an indispensable tool for providing precise position, velocity and time information for many applications like traditional surveying and navigation etc. However, Global Positioning System(GPS), which was developed and is maintained and operated by the U.S. Department of Defence (DoD), has monopolized the world industry and market, and hence there exists the situation that most of GNSS users absolutely depend upon the GPS. In order to overcome the monopoly, some countries, such as Russia. Japan and European Union (EU), have developed their own GNSSs, so-called GLONASS, JRANS and Galileo systems. Among them, the most prospective system in near future is EU’s Galileo system scheduled to launch in 2008. This research has focused on the next generation GNSS system based on GPS and Galileo system with developing a GNSS simulation software, named as GIMS2005, which generates and analyzes satellite constellation and measurements. Based on the software, a variety of simulation tests have been carried out to recognize limits of GPS-only system and potential benefits of integrated GPS/Galileo positioning. Geometry simulation results have showed that comparing with GPS-only case, the number of visual satellites, Dilution of Precision (DOP) values, internal reliabilities and external reliabilities.

Key Words: GPS;Galileo;Geometry;DOP;Reliability