GPS Units and What Makes Them Function

GPS is a system that is space based and is designed to work anywhere in the world in any type of weather conditions. The GPS system delivers velocity which is normally thought of as speed, navigation information and the correct time based on an atomic clock positioned in each GPS satellite. This system consists of at least twenty four satellites which orbit the earth at a height of twelve thousand miles and each one is tilted towards earth at a fifty five degree angle.

To get an accurate reading from the GPS system a receiver must lock onto four different satellites to get time, speed and location. Currently GPS provides signals to any civilian receiver world wide free of charge and usually accurate to within one meter accuracy. The military and government GPS systems are more accurate than civilian systems. Civilian systems are prevented from receiving government or military GPS information for security reasons.

The GPS data received for civilian use is both accurate and available at all times anywhere in the world. The GPS system provides accurate and available data cheaper and more reliably than any other system available to civilians anywhere in the world.

The GPS system is operated by the US Air Force. It is continually monitored for accuracy and reliability. The Air Force Space Command Space and Missile Systems Center is located at Los Angeles AFB in California. The GPS navigational system is maintained by the US Coast Guard for the civilian operational system.