Date of Award


Document Type


Degree Name

Master of Science in Systems Engineering


Department of Systems Engineering and Management

First Advisor

John M. Colombi, PhD.


Improving Space Situational Awareness (SSA) remains one of the DoD’s top priorities. Current research at the Air Force Institute of Technology (AFIT) has shown that modeling and simulation of Geosynchronous Earth Orbit (GEO) SSA architectures can identify optimal combinations of ground and space-based sensors. This thesis extends previous research by expanding design boundaries and refining the methodology. A genetic algorithm examined this increased trade space containing 1022 possible architectures. Experimental trials that would have taken over 100 years on a desktop computer were completed in weeks using a high-performance computer containing over 125,000 cores. The results of the optimizer clearly favor 1.0-meter aperture ground telescopes combined with 0.15-meter aperture sensors in a 12-satellite polar GEO constellation. The 1.0-meter aperture ground telescopes have the best cost-performance combination for detecting Resident Space Objects (RSOs) in GEO. The polar GEO regime offers increased access to GEO RSOs since other orbits are restricted by the 40° solar exclusion angle. When performance is held constant, a polar GEO satellite constellation offers a 22.4% reduction in total system cost when compared to Sun Synchronous Orbit (SSO), equatorial Low Earth Orbit (LEO), and near GEO constellations. This methodology has much greater utility than simply GEO SSA architecture evaluation. Scripting and parallel high-performance computing opens the possibility of solving an entirely new class of problems of interest to the DoD. The results of this research can educate national policy makers on the benefits of various proposed upgrades to current and future SSA systems.

AFIT Designator


DTIC Accession Number