Decade-scale GPS orbit evolution and third body perturbations

Abstract

As of mid-January, 2008, the GPS constellation consists of 31 active satellites, approximately equally divided between Block IIA and Block IIR configurations. Of these active satellites, a subset of the Block IIA satellites have been operating in the same orbit plane and slot loation for more than 10 years. This paper describes the general characteristics of GPS orbit evolution over more than 10 years, based on the high accuracy (decimeter level) ephemerides produced by the International GNSS Service (IGS). This paper examines the contributions of "third-body" luni-solar perturbations on the evolution of the orbits. Copyright © 2008 by the American Institute of Aeronautics and Astronautics, Inc.