What is GPS?

GPS is a satellite-based radio navigation system, initially developed in the early 1960s by the U.S. Department of Defense. GPS consists of a satellite constellation, a ground control network, and user equipment. The satellites broadcast the ranging signals and navigation data which the user equipment receives and computes into user position, velocity and time (PVT).

How does GPS work?

GPS receivers collect signals from satellites in view. They display the user's position, velocity, and time, as needed for their marine, terrestrial, or aeronautical applications. Some display additional data, such as distance and bearing to selected way points or digital charts. The GPS concept of operation is based upon satellite ranging. Users determine their position by measuring their distance from the group of satellites in space. The satellites act as precise reference points.

Do I need to subscribe to a service to use GPS?

No, the United States Department of Defense funds the satellite service with tax dollars. It is free to everyone.

Can I connect my GPS to my computer?

Yes, the vast bulk of modern GPS units allow users to connect to their computers through USB cables. Combined with the computer the GSP device can plot routes, sync maps, store data, along with many other tasks.

Who are the top manufacturers of GPS devices?

Garmin, Magellan, Navman, Hewlett Packard, Lowrance, Trimble, and TomTom are the major producers.