Date of Award

Spring 1-1-2016

Document Type

Thesis

Degree Name

Master of Science (MS)

First Advisor

Jeffrey S. Parker

Second Advisor

Dennis Akos

Third Advisor

Webster Cash

Abstract

Spacecraft operators can use a variety of observables to perform orbit determination throughout a mission. Currently the mission design community has an interest in both autonomous spacecraft operations and in crewed, cis-lunar space missions. Navigators are focusing on ensuring resiliency and redundancy for satellites in the event that a navigation system fails. A spacecraft navigation system that utilizes high definition television (HDTV) signals is explored in this thesis. Using HDTV signals as the source for navigation observables, a satellite navigator can perform orbit determination (OD), either as the primary navigation source or as a backup navigation system. HDTV signals provide strong orbital coverage due to their prevalence around the world. It is shown that due to the high transmission powers HDTV signals are broadcast the signals can be received by satellites out to cis-lunar environments. The ability to extract accurate timing information from the signals in real time is demonstrated at a low CPU resource draw through the implementation of field-programmable gate arrays (FPGA). With the timing extracted from the signals, simulations show that accurate OD for satellites in lunar distant retrograde and halo orbits can be performed using only HDTV signals. These simulations are performed using the DE431 planetary ephemeris, planetary gravity, and solar radiation pressure in both an extended Kalman filter and square root information filter. The full satellite state, range and range-rate biases, and spacecraft reflectance are all successfully estimated by the filters with the presence of errors in the models of the systems dynamics. Since these signals are broadcast around the world at all times, they provide a free signal source for a satellite to utilize at any time more navigation information is needed or a back-up navigation source is required.

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