Improving the Coverage of Earth Targets by Maneuvering Satellite Constellations

Satellite constellations around Earth can be used for observing and/or communicating with targets on the surface. This research mainly addressed maneuvering existing satellite constellations in order to improve coverage of multiple targets over a timespan of 30 to 120 days. However, designing new satellite constellations can also be addressed by using a portion of this research regarding coverage estimation. This research identified a direct relationship between a satellite's orbital geometry and the coverage provided by that satellite. This is accomplished by (1) identifying the view of the satellite orbit from an inertial sphere centered on the Earth, and (2) utilizing information from all the orbital views across the target's inertial latitude on order to arrive at lower and upper bounds on coverage. Altering a satellite orbit also alters the coverage that it provides. Gauss' variational equations were used to find maneuvering strategies that effect maximal changes in orbital geometry. These distinct maneuvering strategies were then complied into a list that will be used in the subsequent optimization.