From the thesis abstract: "Recent evidence suggests that there are increasing levels of maritime activity in the Arctic Circle which requires new methods for meeting the Arctic maritime information needs of the United States and allies. Information needs are particularly acute in the most critical areas of the Arctic for the United States such as the U.S. Exclusive Economic Zone. Because the Arctic environment is inhospitable to lower atmosphere intelligence, surveillance, and reconnaissance methods with which to gather information, space-based surveillance such as synthetic aperture radar sensors are likely the best way to meet ever-increasing Arctic information needs. Modeling and Simulation was employed to determine a practical constellation design of space-based radars to remotely sense the totality of the Arctic Circle and the portion of the U.S. Exclusive Economic Zone that lies within it. Analysis of single orbital plane, Walker, and custom constellation designs determined that a constellation of three sensors strikes a balance between coverage and efficiency for Arctic surveillance. A constellation of radar sensors in sun-synchronous orbits with ascending node spacing of 50 degrees apart achieved optimality in coverage time, efficiency, and consistency in sequential 24-hour intervals."
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