Experiences in implementation and use of the square root information filter/smoother for orbit determination

Abstract

Gerald J. Bierman designed an orbit determination square root information filter/smoother component for TRACE, a large orbital analysis program maintained and distributed by The Aerospace Corporation.This paper is a largely anecdotal account of what factors shaped implementation decisions, how the system was tested, how it has performed in practice, what niodifica tions have been made in response to requests from users, and how it stacks up today against our original goals and predictions.