Global Positioning System

 The Global Positioning System, usually called GPS, is the Earth's only fully-functional satellite navigation system. A constellation of more than two dozen GPS satellites broadcasts precise timing signals by radio to electronic GPS receivers which allow them to accurately determine their location (longitude, latitude, and altitude above mean sea level) in real time, day or night, in any weather.

Since GPS was declared fully operational in 1993, it has become a vital global utility, indispensible for modern navigation on land, sea, and air around the world, as well as an important tool for map-making, and land surveying. GPS also provides an extremely precise time reference, required for some scientific research. A well known example concerns the study of earthquakes. For astronomical purposes GPS has an enormous importance because it is a very precise source for time information without which the interferometric studies, as well as those concerning double stars, planned in the Project would not be realizable. GPS combined with binaries listed in the fundamental catalogues enables significant improvements  of reference frames.

  Copyright 2006.  Faculty of mathematics Studentski trg 16, Belgrade, Serbia and Montenegro