Fast Generation and Tracking of GNSS Visibility and Dilution-of-Precision Regions Using Level Set Methods Nora E.H. Stack, University of California Los Angeles Walter Z. Cai, University of California Los Angeles Scott Manifold, University of California Los Angeles Ana C. Perez-Gea, University of California Los Angeles Sante R. Scuro, The Aerospace Corporation Joseph E. Papac, The Aerospace Corporation Yanina Landa, The Aerospace Corporation Jaime Y. Cruz, The Aerospace Corporation Paul D. Massatt, The Aerospace Corporation Frederick E. Fritzen, The Aerospace Corporation BIOGRAPHIES Nora E.H. Stack is a recent graduate in Mathematics from St. Mary’s College of Maryland. She will be pursuing a PhD in Applied Mathematics at the Colorado School of Mines beginning in the Fall of 2014. Walter Z. Cai is a recent graduate in Mathematics from Cornell University and will be pursuing an M.S. degree in computer science at UW-Madison in the Fall of 2014. Scott H. Manifold is a recent graduate in Mathematics from the University of California, Riverside and will be pursuing a PhD in Engineering Sciences and Applied Mathematics at Northwestern University in the Fall 2014. Ana C. Perez-Gea is a recent graduate in Applied Mathematics from the Mexico Autonomous Institute of Technology in Mexico City. She is currently a research assistant at the Center for Research and Teaching in Economics also in Mexico City. Sante R. Scuro is a Senior Member of the Technical Staff in the Navigation and Geopositioning Systems Department at The Aerospace Corporation. He has an M.S. degree in High Energy Physics from Texas A&M University. Joseph E. Papac is a Senior Member of the Technical Staff in the Structural Dynamics Department at The Aerospace Corporation. He has a doctorate in Mechanical Engineering from UC Santa Barbara. Yanina Landa is a Member of the Technical Staff in the Imagery Products and Exploitation Department at The Aerospace Corporation. She has a doctorate in Mathematics from UCLA. Jaime Y. Cruz is the Associate Director of the Navigation and Geopositioning Systems Department at The Aerospace Corporation. He has a doctorate in Geodesy from The Ohio State University. Paul D. Massatt is a Senior Engineering Specialist in the Navigation and Geopositioning Systems Department at The Aerospace Corporation. He has a doctorate in Applied Mathematics from Brown University. Frederick E. Fritzen is a Senior Engineering Specialist in the Navigation and Geopositioning Systems Department at The Aerospace Corporation. He has a doctorate in Mathematics from the University of Southern California. ABSTRACT With the advent of multi-Global Navigation Satellite Systems (GNSS), many organizations will need to be able to evaluate GNSS coverage efficiently. Satellite visibility regions and Dilution-of-Precision (DOP) calculations represent a natural application of level set interface representation and tracking methods. Nevertheless, level set analysis has yet to be examined with respect to computational satellite performance simulations. Undergraduate students from the UCLA Research in Industrial Projects for Students (RIPS) program combined their efforts with engineers from The Aerospace Corporation (Aerospace) to develop computationally efficient visibility regions and DOP displays using Level