A robust estimation method in orbit improvement

Orbit improvement is studied via processing simulated optical data of 20 satellites. Using our criterion the fraction of outliers falls to less than 10% in most cases. Our method, which ensures the accuracy of orbit improvement, consists in using the Huber estimator twice, followed by iterating the Hampel estimator until convergence. The parameters C0 and C1 in the Hampel estimation may be given the fixed values of 2.2 and 3.6, while the value of C2 varies in a definite way with the size of the outlier considered.