GPS System

Navigating the Globe with a GPS System
From Early Military use to more Widespread Acceptance

Better known as GPS, the global positioning system is a one-of-a-kind global satellite navigation system. An assemblage of greater than two dozen GPS system satellites can broadcast exact time signals to GPS system receivers and help them calculate their longitudinal, altitude and latitudinal locations at any time of the day or night and in any weather conditions. It is most useful in global navigation whether by sea or land or even air and is also useful for map making and land surveying.

A GPS system will provide very useful time reference that is an essential part of telecommunications and is also vital for scientific research for studying earthquakes and the like. The GPS system was first developed by the US Department of Defense and was called NAVSTAR GPS short for Navigation Signal Timing and Ranging GPS and a satellite constellation is under the control of the 50th Space Wing based at SchrieverAir Force Base. Even though maintaining a constellation of satellites is a very costly affair, it is available free of cost to civilian users as an act of public good.

By late 2005, the number of satellites was increased by incorporating new-generation technologically advanced GPS system satellites, which was capable of transmitting a second satellite signal called L2C for giving more accurate and reliable information. The future holds a lot of scope for more signals being added that can be of military use as well as increase the present coverage of L2C.

The Wide-Area Augmentation System is a very accurate GPS system signal that can reliably give signals with accuracies of up to within 2 meters for receivers that are compatible to receive these signals. There are also more improvements being made to further the accuracy of the signal to within 1 centimeter (or half an inch).

The military uses GPS systems for targeting different military weapons such as cruise missiles and precision guided munitions. Also, it can help in providing ground troops with better location information. There is much use of the GPS system in the field of navigation where it can be used in planes, cars and ships as well as in a PDA, car, personal computer and for the visually impaired. Surveyors use it for land surveys to locate boundaries.

With low cost GPS systems costing as little as US$90, hand held GPS receivers have found use in recreational hand held applications such as Geocatching that enables the user to travel to specific latitudinal and longitudinal positions to seek out objects that may have been stored by other Geocatchers. It is also available for use on airplanes though they cannot be used while the plane is taking off and landing.