Online Resources: There are several descriptions/explanations of the Global Positioning System available online, including:

Books and Articles: There are many books and articles on GPS, including:

El-Rabbany, Ahmed (2002) Introduction to GPS, ARTECH House.
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Kaplan, Elliott (1996) Understanding GPS, ARTECH House.
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Tsui, J.B. (2000) Fundamentals of Global Positioning System Receivers, John Wiley and Sons.
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