Orbit Determination at a Single Ground Station Using Range Rate Data

Abstract

The solution of the spacecraft orbit determination problem is highly dependent upon the type of tracking data available at the ground station. Many algorithms exist for different types and combinations of tracking data. Well-funded tracking stations are typically able to supply six or more observed parameters simultaneously, enabling explicit solution of the orbit determination problem. The low-cost ground station under development at San José State University will initially be able to measure only Doppler shift as a function of time, thereby providing slant range rate as the single observable parameter. An algorithm enabling explicit solution of the orbit determination problem using range rate exclusively was not found, but orbit estimate improvement is still possible via differential correction. By utilizing a differential correction scheme in conjunction with a batch least squares estimator along with convergence improvements, the task of maintaining an acceptably accurate knowledge of the spacecraft orbit is made possible for a single ground station receiving a single measured parameter, even at higher levels of measurement noise and bias than those expected at the ground station.