This applet demonstrates the GPS (Global Positioning System).
To try this
simulation:
Move the helicopter by click-dragging the mouse. Notice how the helicopter's position is triangulated using the signals transmitted from nearby satellites.
What's Going On?
GPS is a network of satellites in orbit around the earth. These satellites transmit signals which allow GPS users to locate themselves anywhere on the earth. The GPS units provides latitude and longitude as well as the precise time. The applet shows the latitude and longitude of the helicopter.
There's More!
Advances in large scale integrated circuit technology allow a complex and computationally intense device to be reduced in cost and available to nearly everyone. Today you can purchase a GPS receiver that will fit in your pocket and will continually display your location. Coupled with a computer, the GPS system allows you to continually track direction of travel, speed, estimated time of arrival and almost any other navigational information you could require. GPS units have been used to track whales, find lost hikers, and locate friend and foe on the battlefield.
