Characterization of PDOP for Locating a Geostationary Satellite using TWSTFT Links

TWSTFT is one of the most accurate methods to compare and synchronize time scales between remote stations connected by a geostationary satellite. The high accuracy of the TWSTFT time measurement allows it to be used to locate a geostationary satellite. This results in a lower location uncertainty, which decreases the number of maneuvers made to avoid the debris collision. The Brazilian geostationary satellite (SGDC) and the time and frequency standards laboratories in Latin America could be used to improve the location of the SGDC with the TWSTFT links. The satellite location uncertainty is calculated using a geometry factor called PDOP. The results indicate that there is a way to accentuate the reduction of the PDOP and, consequently, decrease the location uncertainty of the geostationary satellite.