How The GPS System Came To Be

The design of GPS is based partly on similar ground-based radio navigation systems, such as “LORAN” and the “Decca Navigator” developed in the early 1940s, and used during World War II.
The first satellite navigation system, “Transit”, used by the United States Navy, was first successfully tested in 1960. Using a constellation of five satellites, it could provide a navigational fix approximately once per hour.

The design of GPS is based partly on similar ground-based radio navigation systems, such as “LORAN” and the “Decca Navigator” developed in the early 1940s, and used during World War II.