ABSTRACT
The first US satellite navigation system was launched by the Department of Defense (DoD) in 1978. It was then called NAVSTAR (short for “Navigation System with Timing and Ranging”), which became fully operational in 1993.1The primary reasons for the development of this system, which cost between $10 and $12 billion dollars to field, were precise weapon delivery and standardization of the use of navigation systems within the US military.2
