Formation Flight for Close Satellites With GPS-Based State Estimation Method

This article focuses on the specification of satellite relative state estimations with an Extended Kalman filter (EKF) using the target and tracker satellite positioning derived from the Newton Raphson Method (NRM). Although not true in real applications, it is assumed that the system dynamic model and measurements are correct in state estimations with EKF approximation. In this study, target and tracker satellite initial condition values have been taken from simulation data. Orbital states are Keplerian orbital parameters, and Global Positioning System (GPS) receiver values are the Earth-Centered Inertial (ECI) reference frame. The Pseudo-ranging approach has been used to find the positions of the target and tracker satellites. The random errors have also been considered for the actual distance between the target and tracker satellites. In this study, satellite relative state vectors have been estimated with an analyzed scenario which the target and tracker satellites localization have been estimated individually.