Over the years, people have been using different techniques to navigate across the world. Traditionally, people used to depend on landmarks and stars to travel between different locations, while compasses and maps helped them from getting lost. The discovery of the Global Positioning System (GPS) made people no longer have to rely on these traditional positioning techniques to find their way around.
History of Global Positioning System (GPS)
GPS also is known as Navstar project started in the year 1973 and became fully operational in 1994. This system is funded and run by the United States Department of Defense. Originally, this system was intended for military purposes only but was made available to public use on completion of the project.
GPS consists of a network of 24 active satellites located nearly 20000 kilometres above the Earth’s surface. Each satellite broadcasts different signals which can be tracked by a GPS receiver on earth, which are then analyzed by the GPS receiver to determine its precise location. The signals operate in all weather conditions but can’t penetrate through solid objects, so GPS receivers perform best when they have a clear view of the sky.
GPS contains a control segment which has a system of tracking stations located around the world. The master control facility is located at Schriever Air Force Base in Colorado. It receivers come in all different shapes and sizes, are widespread and are affordable. Today, GPS receivers can be found in watches, phones, tablets, computers, cars and a wide variety of other devices. This segment consists of:
- A master control station
- An alternate master control station
- Six dedicated monitor stations
- Four dedicated ground stations
The GPS user segment has user segment and GPS receivers. These receivers transform SV signals into velocity, position and time estimates. It needs four satellites to measure the Four dimensions of X, Y, Z and time. GPS receivers are helpful in navigation, time dissemination, positioning and some other research. Navigation is the key function of GPS. it is useful for ships, aircraft and even ground vehicles.
Fast Facts on Global Positioning System (GPS)
- GPS became fully operational in 1994.
- It may be free for the public to use but it costs nearly 2 million dollars for the US government.
- GPS receivers can determine your position anywhere on the Earth. Including the oceans.
- A normal GPS satellite travels nearly 14000 km per hour.
- These signals can travel through most of the plastics, but cannot pass through wood and concrete.
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