A GPS, or Global Positioning System, is a satellite-based navigational system. It is comprised of 24 satellites that the U.S. Department of Defense placed in orbit, originally for military operations. In the 1980s the U.S. government opened up the system for civilian use. Since that time Global Positioning Systems have become increasingly popular for numerous applications.
GPS works in any weather, in almost any location, and at any time. The only places where signals cannot be received are caves, tunnels, inside buildings, and under water. Using it does not require a subscription fee or setup charge-it's available free to anyone who wants to use it. GPS receivers are extremely accurate, often to within 15 feet or less.
The GPS consists of three parts: satellites that orbit Earth, control and monitoring stations on Earth, and receivers owned by users. GPS receivers pick up signals that satellites broadcast. The receiver provides latitude, longitude, altitude, and time.
Many automobiles now have built-in GPS. Some automotive GPS by Garmin and other manufacturers contact emergency assistance, while other systems also provide location and direction information.
Occupational applications of GPS continue to multiply. It has increased the efficiency and decreased the cost of surveying by reducing site setup time and dramatically improving accuracy. Foresters and farmers use GPS. Geologists, biologists, and other scientists use it for its precision timing capability and for accurate position information. Commercial fisherman, and professional mariners use GPS.
Drivers and dispatchers use it to improve customer service and fleet tracking. It is an essential tool for public safety, emergency response, and disaster relief. In the air, GPS improves pilot communication, navigation, and hazard avoidance. GPS is revolutionizing space exploration.
Recreational uses of GPS navigation systems continue to expand. Hikers, hunters, snowmobilers, fishermen, and boaters use it. In fact, anyone who wants to keep track of where he or she is or figure out how to get from one place to another will find a GPS useful. Without GPS the worldwide activity of geocaching would not be possible. GPS has even improved the game of golf by telling golfers how far they have to hit their balls.
GPS receivers range from relatively small, portable, and affordable handsets for recreational use to an innovative technology developed by NASA for high Earth orbit missions. Enhanced technology is making GPS more available within heavy foliage environments. The increasing incorporation of GPS into cell phones improves emergency response and popularizes its technology.
The newest systems are both more sophisticated and more user friendly than earlier systems. Manufacturer support services enhance the accessibility and availability of the technology.
Manufacturers and distributors provide guidance on which GPS systems are best for specific applications. With many choices of GPS receivers now available, consumer reviews also inform purchases. The Internet is a powerful resource for information on its technology, applications, and equipment and for the purchase of new and refurbished receivers. Commercial, governmental, and scientific websites educate the public on this growing technology that will soon become part of everyday life.