The GPS project was started by the U.S. Department of Defense in 1973. The first prototype spacecraft was launched in 1978 and the full constellation of 24 satellites became operational … See more

The GPS satellites carry very stable atomic clocks that are synchronized with one another and with the reference atomic clocks at the ground control stations; any drift of the clocks … See more

While originally a military project, GPS is considered a dual-use technology, meaning it has significant civilian applications as well. See more

Problem statement
The receiver uses messages received from satellites to determine the satellite positions and time … See more

The GPS project was launched in the United States in 1973 to overcome the limitations of previous navigation systems, combining ideas … See more

The current GPS consists of three major segments. These are the space segment, a control segment, and a user segment. The See more

The navigational signals transmitted by GPS satellites encode a variety of information including satellite positions, the state of the internal clocks, and the health of the network. … See more