GPS is the short form of Global Positioning System. Global positioning system (GPS) is a technology that utilizes the radio waves, satellites and various types of receivers to track a specific location.
By the use of satellite signals the GPS helps one to locate any place or provide one with the distance from one place to another. The satellite signals allow the GPS receivers to locate, calculate and display the correct speed and time information to the user.
The GPS automatically pick up our current location. GPS units come in small pocket sized hand-held models like that of our mobiles, tablets, watches, palmtops and they are also designed to use in cars for searching any place and also to find certain directions. GPS also provides us with all the route directions.
The United States, Department of Defense (DOD) have first coined the technology of the global positioning system, for military application. A GPS unit works off of a network of 24satellites that orbit the earth, 24 hours a day.
These satellites are solar powered machines that are coordinated in a manner that at least 4 GPS are accessible from any one location. A clear view of the sky is necessary for a GPS unit to work properly.
From among a constellation of 33 available satellites, the GPS works by capturing the signals from three or more satellites. GPS receivers use the principle of Trilateration to pinpoint the location.
GPS receiver converts the location, speed and time information in to a useful visual display format. Whichever weather condition may be, GPS always works correctly. However GPS signals can be blocked by dense forest, canyon walls or space wells, as such some locations may be there where we cannot find GPS navigation.
Imagine standing anywhere in the Earth with threesatellites above (say A, B and C). If we know how far we are from the Satellite A, then we are somewhere on the red circle. If we know how far we are from satellite B, then it is known that we are somewhere in the blue circle and we would do the same for satellite C. this is what is done by the GPS, although the GPS also can locate our positions if we were in the overlapping spheres.
The accuracy of the position increases by the number of satellites above us. The GPS needs an unobstructed view of the sky so it accurately gives information outdoor.
As we learned that GPS works off of using radio waves, these radio waves are electromagnetic energy which mean that they travel at the speed of light. The GPS receiver can figure out how far the signals have to arrive.
Basic GPS measurements yield only a position, neither speeds nor direction. Most of the GPS units can automatically derive velocity and direction of movement from two or more position measurements. The recent technologies is used to overcome the drawbacks that were faced earlier when in a dense forest or under canopy wall.