Orbit determination of TOPEX/POSEIDON and TDRSS satellites using TDRSS and BRTS tracking

TOPEX/POSEIDON (TP) orbits were computed from measurements taken by the US Tracking and Data Relay Satellite (TDRS) System (TDRSS). TP orbits can be computed from TDRSS tracking with an accuracy on the order of 10 cm in the radial direction and 20 cm in absolute position if the orbits of the TDRSs are known with high accuracy. Orbits of TDRSs can be determined with an estimated accuracy significantly better than 10 m in the radial direction, and 20 m in absolute position, if the high-accuracy TP orbits from SLR/DORIS tracking are used as constraints in orbit computations of the TDRSs, and use is made of TP tracking data by TDRSS. If the orbits of TP and the TDRSs are estimated together from both TDRSS tracking data and data acquired by the Bilateration Ranging Transponder (BRT) System (BRTS) and no a priori information is used, these accuracy levels are 25 cm and 2-5 m for TP, and 10 m and 20-30 m for the TDRSs, respectively. Orbits of the TDRSs can be computed with an accuracy of 10 m in the radial direction and 30-40 m in absolute position if only BRTS tracking data is used. Finally, maneuvers of TDRSs and TP have been estimated with high accuracy from BRTS and TDRSS tracking data. (C) 1997 COSPAR. Published by Elsevier Science Ltd.