How was the GPS created ?

Question

how was it invented

Answer 1

Why:  The military needed some method of accurately determining the position of their ships, planes, etc. along with targets.

How:  Someone who was real good at trigonometry figured out how to determine positions using triangulation and highly accurate timing information from satellites.

Answer 2

GPS is a re[palcement for LORAN (LOng Range Aid to Navigation) which is a terrestrial radio navigation system using low frequency radio transmitters that uses multiple transmitters (multilateration) to determine location and/or speed of the receiver. LORAN was an American development of the British GEE radio navigation system (used during World War II). While GEE had a range of about 400 miles (644 km), early LORAN systems had a range of 1,200 miles (1,930 km).

The basic idea to build up a navigation system using satellites already existed before World War II.  The first satellite navigation system, Transit, used by the United States Navy, was first successfully tested in 1960. The first experimental Block-I GPS satellite was launched in February 1978.

Answer 3

It was created by the US military as replacement for the Transit system, making it lighter and more accurate by using better technology and lighter receivers - as well as moving more intelligence into the receiver. It was already early in the project decided, that the costs can be cut by allowing mass production of the receivers and civil use.

For keeping the military accuracy secret, two codes are use: A public code sequence for the first frequency of the satellite (L1), and a secret code sequence for the second (L2).

Answer 4

The US military developed it as a means of navigation for ships and aircraft.

It was eventually made available to the public.

Answer 5

it was designed by army nerds in teh 1970s.

Answer 6

The GPS system consists of 24 continuously operating satellites - and these satellites each broadcast the same thing:  the time.  

Each satellite is basically a very accurate clock, each broadcasting the same time.  

To us on the ground, a GPS unit receives the signals, and, based on the slight difference in arrival time, calculates to within a few feet (depending on the unit, and the quality of the signal) WHERE you are.  

To determine a point in space, you need 3 coordinates.  By knowing how far away from three  other points you are, you can calculate *the* spot in space you're at.   At any one time, I believe there are 4 GPS satellites within line-of-site over just about any point of the Earth - from those satellites, your GPS unit deciphers what the difference in time codes are, and through some simple arithmetic, figures your location.