Satellite Systems: Location Services and Telemetry

This chapter describes the most widely utilized commercial satellite navigation systems such as American global positioning system (GPS), Russian Global Navigation Satellite System (GLONASS) and European GALILEO. GLONASS is meant for both military use as well as for civilians. All the satellite navigation systems require complete or close to line of sight between sufficient amount of satellites and receiver in order to function, whereas the cellular systems can provide a rough estimate for the location even with blocking obstacles in the radio path, but with reduced accuracy of location. The satellite systems can also be utilized in many other tasks, including measurements of the weather and other events of the Earth. Also space investigation has an important role, which can be done via satellites for exploring the structure and phenomena of deep space. In general, the delivery of measurement data, that is, telemetry, is a major task of satellites.