A space navigation system is a system of satellites that provide autonomous geo-spatial positioning with global coverage. It allows small electronic receivers to determine their location (longitude, latitude, and altitude) to high precision (within a few metres). United States NAVSTAR Global Positioning System (GPS) and the Russian GLONASS are global operational GNSSs. China’s Beidou navigation system, European Union’s Galileo positioning system and India’s IRNSS are examples of regional navigation system.
The basic purpose behind any space based navigation system is to identify the location of an object on earth and gathering information about it in real time. In some cases, it may provide speed and direction of an object moving on surface of Earth. Such navigational systems are useful both for civilian and military purposes. Many more new civilian applications are being invented. For Example, tracking endangered species in particular area, determining Earth’s movement after earthquake besides it convention usages in terrestrial, Aerial and Marine Navigation, Disaster Management, Vehicle tracking and fleet management, Integration with mobile phones, mapping and Geodetic data capture etc.
Indian Regional Navigation Satellite System (IRNSS), a constellation of seven satellites required to provide a regional navigational coverage under the control of Govt. Of India. While GPS/GLONASS/Galileo/COMPASS are meant for global operations and have provisions (or have plans) for about 26 to 35 satellites each.
