Abstract

The aim of the Navigation Overlay Service (NOS) payload (NOS P/L) is to provide an overlay function with supplementary services to the current operating GPS. This kind of services uses existing GEO telecommunications satellite to transmit overlay signals to provide improvement of accuracy, system’s integrity information, wide area differential corrections. This service will be provided, in Europe, by EGNOS (European Geostationary Navigation Overlay Service). A similar service, called WAAS (Wide Area Augmentation Service) will operate in U.S.A. Similar services are also provided in Japan with MT-SAT. The paper will present the architecture of the payload manufactured by Alenia Spazio and embarked on the ESA Artemis satellite.