ABSTRACT
This chapter discusses Global Navigation Satellite System (GNSS), how it works, its potential uses and some of the issues that lie between the new status of the two existing systems and their implementation as full civil aviation global satellite navigation systems. International Civil Aviation Organization (ICAO) has given the generic term: GNSS to the concept of navigation by satellite. The ICAO concept is quite definite in its preference of GNSS for navigation, seeing it as providing independent on-board position determination, and being a key feature of future Communication, Navigation, Surveillance - Air Traffic Management systems. Satellite navigation presents opportunities for standardized worldwide civil aviation operations using a common navigation receiver and for significant improvements in safety, capacity, service flexibility and operating costs. The ground monitoring stations transmit information to one or more master stations which derive the health status of the satellite signals and integrate information into a composite integrity signal.
