Title: Relative navigation to non-cooperative targets in LEO: achievable accuracy from radar tracking measurements
Authors: Ralph Kahle; Martin Weigel; Michael Kirschner; Sofya Spiridonova; Erin Kahr; Klemens Letsch
Addresses: German Aerospace Center (DLR), German Space Operations Center (GSOC), Oberpfaffenhofen, 82234 Wessling, Germany ' German Aerospace Center (DLR), German Space Operations Center (GSOC), Oberpfaffenhofen, 82234 Wessling, Germany ' German Aerospace Center (DLR), German Space Operations Center (GSOC), Oberpfaffenhofen, 82234 Wessling, Germany ' German Aerospace Center (DLR), German Space Operations Center (GSOC), Oberpfaffenhofen, 82234 Wessling, Germany ' Department of Geomatics Engineering, Schulich School of Engineering, University of Calgary, 2500 University Drive NW, T2N 1N4, Canada ' Fraunhofer Research Institute for High Frequency Physics and Radar Techniques (FHR), Fraunhoferstr. 20, 53343 Wachtberg, Germany
Abstract: Any future space debris removal or on-orbit servicing mission faces the problem of the initial relative orbit determination of the servicing satellite to the non-cooperative target. In this work, we analyze the relative navigation accuracy that can be achieved in low Earth orbit, by using ground-based orbit determination from radar tracking measurements for the target, and classical GPS-based orbit determination for the servicing satellite. The analysis is based on the radar tracking measurements obtained from a 10x10x34 cm small object at an altitude of 635 km. The results show that the relative orbit can be determined with accuracy down to 2 m (RMS) in the semi-major axis, and down to 20 m (RMS) in both the radial and normal separations. From the results, we derive requirements on radar-tracking campaigns.
Keywords: relative navigation; radar tracking; on-orbit servicing; space debris removal; non-cooperative targets; LEO; low Earth orbit; orbit determination; servicing satellites.
DOI: 10.1504/IJSPACESE.2014.060112
International Journal of Space Science and Engineering, 2014 Vol.2 No.1, pp.81 - 95
Received: 11 Jul 2013
Accepted: 18 Sep 2013
Published online: 13 May 2014 *