The Global Positioning System

Military Origins

The Global Positioning System (GPS) originated from military needs during the Cold War, aiming to enhance navigation accuracy for nuclear submarines. Gary Arndt explains that the first satellite navigation system, Transit, launched in 1960, provided location data with an accuracy of up to 200 meters, which was sufficient for military purposes but not ideal for precise navigation 1. The development of the Navstar system in 1973 marked a significant milestone, integrating various existing technologies to create a more reliable navigation system, initially intended for exclusive military use 1.

In 1973, a team in the Pentagon laid down a framework for a system that synthesized all of the various programs which currently existed and created a new system called Navstar.

--- Gary Arndt

The launch of satellites equipped with atomic clocks further enhanced the system's accuracy, setting the stage for the modern GPS we rely on today.

   

Civilian Expansion

The transition of GPS from a military tool to a civilian utility was catalyzed by a tragic event in 1983 when a Korean Airlines flight was shot down due to navigational errors. Gary Arndt notes that this incident led President Reagan to open GPS for civilian use, albeit with selective availability that limited accuracy for non-military users 1. This policy changed in 2000 when President Clinton ended selective availability, allowing civilians the same level of accuracy as the military, which significantly expanded GPS applications 1.

The next big advance in GPS occurred on May 1, 2000, when President Clinton ordered the end of selective availability.

--- Gary Arndt

The affordability of GPS technology has since increased, making it ubiquitous in modern devices, with the system relying on a constellation of satellites and ground stations to provide precise location data 2.