Analysis of Angles-Only Hybrid Space-Based/Ground-Based Approach for Geosynchronous Orbit Catalog Maintenance

Abstract

Geosynchronous Equatorial Orbit (GEO) is critical to Earth communications, weather monitoring, and national defense. Orbit estimation of GEO objects is difficult due to physical constraints placed on ground-based tracking devices such as weather, object range, lighting conditions and tracking frequency restrictions. These constraints are commonly mitigated through the use of two-way signaling devices for cooperative GEO satellites. However, determining the position and velocity of uncooperative GEO satellites and/or objects is more challenging. The objective of this paper is to develop an efficient tool to quantify the increased orbit determination accuracy of objects in the GEO catalog when the Air Force Space Command Space Surveillance Network (AFSPC SSN) is augmented with space-based angles-only measurements from a sensor in a unique near-GEO orbit. To accomplish this, a linear covariance tool is developed and validated by Monte Carlo analysis over a range of problem parameters. It is shown that linear covariance analysis is an efficient approach in determining the covariance of the position and velocity estimation errors of an uncooperative GEO object. Additionally, the linear covariance tool is used to perform error budget analysis.