the European Geostationary Navigation Overlay Satellite Service (EGNOS) is being built to augment the GPS and GLONASS satellite navigation systems so that they can be used for safety-critical applications such as aircraft navigation. GPS data will be collected by 34 Ranging and Integrity Monitoring Stations (RIMS) in 22 countries and sent every second to Master Control Centres (MCCs) in the UK, Germany, Spain and Italy for the addition of accuracy data. This augmented GPS data will then be transmitted via satellites, with support from several Navigation Land Earth Stations (NLES). EGNOS will allow its users to determine their position to within five meters, instead of about 20 meters at present.

VISIT THE OFFICIAL EGNOS SITE