Application of TDRSS in Chinese Space TT&C

Tracking and Data Relay Satellite Systems(TDRSS),which feature high coverage and data transmission capability,have become a key part of space TTC(Tracking,Telemetry and Command) networks.The role of TDRSS is more and more significant in improvement of China's space TTC networks and enhancement of their TTC capability for LEO(Low Earth Orbit) and MEO(Medium Earth Orbit) spacecraft with establishment and development of China's own TDRSS.The application demands of China's space TTC missions for TDRSS are analyzed based on the characteristics of TDRSS.An approach is proposed for application of TDRSS in TTC for launch vehicles,spacecraft orbit injection,manned spaceflights and routine management of in-orbit spacecraft.A summary of key technologies is given for TTC for launch vehicles,spacecraft orbit injection and LEOP(Launch and Early Orbit Phase),spaceship return phase and multi-access links.