Date of Award


Document Type


Degree Name

Master of Science in Electrical Engineering


Department of Electrical and Computer Engineering

First Advisor

Alan L. Jennings, PhD.


The Global Positioning System (GPS) constellation provides ranging information that delivers inexpensive, high precision positioning for terrestrial users. Satellites in Low Earth Orbit (LEO) can use an onboard GPS receiver resulting in meter-level navigation solution accuracy. There are limitations to using GPS for positioning for satellites above LEO. The number of GPS satellites who's signal can be received decreases as the receivers altitude approaches that of the GPS constellation. Above the GPS constellation, the available GPS signals for ranging will originate from satellites on the opposite side of Earth. This research calculates the available GPS signals to the receiver and determines the expected position error, while considering the effects from a low signal to noise ratio, poor geometry, and signal shift caused by high relative velocity.

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DTIC Accession Number