Global Positioning System, popularly known as GPS, is one of the history’s most exciting and revolutionary developments, and new uses for it are constantly being discovered. GPS shows the position of any object exactly on earth, any time, in any weather and anywhere .The Global Positioning System consists of three parts space segment, control segment and user segment. The cost of maintaining the system is approximately US$ 400 million per year, including the replacement of ageing satellites. The GPS satellites, 24 in all, 11000 nautical miles above the earth, transmit signals that can be detected by anyone with GPS receiver. Using this receiver, we can be able to determine the location of the object with great precision usually of about several centimetres with the help of advanced technology.
Global navigation has demanded for the development of GPS. So, GPS is mostly being used for navigation. As a part of this, it is being used in hydrographic survey. For safe navigation, sufficient depth of water is required in any port. To determine the depth available in the Port area, hydrographic surveys are required to be conducted. The Global Positioning System has many more applications. These days GPS is finding its way into cars, boats, planes, construction equipment, movie making , farm machinery, even laptop computers . GPS is used to determine the routes for planes, ships, etc. GPS has many uses in both military and civilian life. Soon GPS will become almost as basic as the telephone, may be a universal utility system.
GPS is an intermediate circular orbit (ICO) satellite navigation system used for determining one’s precise location and providing a highly accurate time reference almost anywhere on Earth and in Earth orbit. The GPS was designed by and is controlled by the United States Department of Defence. About three crore people around the world are using GPS. The utilization of this system is increasing year by year due to increase in number of users of cell phones and vehicles. The availability of this system for utilization by all for free is leading to the future developments of this system.
Man has been trying to figure out a reliable way to tell where he is and to help himself locate where he was going. Early man probably used stones and twigs to mark the places and routes but these got washed out due to rain or snow. The problem became still worse when he started to explore oceans. This created the need for GPS. The principle behind the working of GPS is the measurement of distance between the receiver and satellites. The high frequency radio transmitters, high above the earth, sending a high frequency radio wave with a specific coded signal can cover a large area and still overcome much of the noise, encountered on the way to the ground. This forms one of the basic principles behind the development of GPS. Two GPS developers have received the National Academy of Engineering Charles Stark Draper prize year 2003. On February 10,1993, the National Aeronautic Association selected the GPS Team as winners of the 1992 Robert J. Collier Trophy, the most prestigious aviation award in the United States.