Results from the GPS Experiment on Equator-S

Abstract

An encouraging concept for position determination of geostationary satellites is the use of the Global Positioning System (GPS). Although the geostationary orbit is well beyond the orbits of the GPS Navstar satellites (i.e. 20 000 km), it is possible to use GPS - as demonstrated with the GPS experiment on board of the German Small Satellite Equator-S. The experiment data have significant impact for the future use of GPS receivers on-board geostationary satellites. In the past, GPS receivers have only been used well below the orbital altitude of the GPS satellites. The reception of GPS signals at greater altitudes has been demonstrated within the Equator-S GPS experiment. As part of this, GPS signals have also been received from the antenna side lobes of the GPS satellites. The maximum altitude where the GPS receiver provided measurements was about 61 000 km.