Precise Maneuver Calibration for Remote Sensing Satellites

Abstract

Orbit maintenance maneuvers are performed as necessary to maintain the spacecrafts trajectory to within a specified tolerance relative to a set of predefined reference orbital parameters as depicted by the mission objectives. After each executed maneuver, the rate of change in velocity is calibrated to deduce the thruster’s performance and to assist with future maneuver planning. For the GRACE mission, the maneuver performance can be independently deduced from the in-flight telemetry data and by processing the GPS navigation messages. Alternatively, one can also exploit the precise GPS observables for maneuver calibration. This precise calibration approach is implemented in the precise orbit determination and has been successfully demonstrated using the GPS data from the GRACE spacecraft. The analysis not only yields remarkable improvement and consistency in the calibration performance but also in the GPS measurement residuals and the reconstructed orbits of GRACE in the vicinity of the maneuver.