GPS receivers
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world of nothing
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GPS,
technology
Study concludes that pigeons have a natural sort of GPS to locate. They are located based on the Earth's magnetic field.
Our ancestors had to resort to extreme measures to not get lost: they erected monumental landmarks, drew detailed maps and with great difficulty learning to read the stars in the sky.
Things are much, much easier today. For less than $ 100 you can buy a handheld device that tells you exactly where you are on Earth at any time. As long as you have a GPS receiver and a clear view of the sky will never be lost again.
In this article, we'll see how convenient these guides perform this amazing trick. As we shall see later, the Global Positioning System is vast, expensive and involves a lot of technique, but the basic concepts in action are pretty simple and intuitive.
When people talk about "a GPS," they usually mean a GPS receiver. The Global Positioning System (GPS) is actually a constellation of 27 satellites in orbit around the Earth (24 operational and 3 extras in case one fails). The U.S. military developed and implemented this satellite network as a military navigation system, but soon opened it up to others.
Each of these satellites solar-powered and weighing 3 to 4 billion pounds (approximately 1360 to 1814 kg) circles the globe at about 19,300 kilometers, making two complete rotations every day. The orbits are arranged so that at any time of day, anywhere on Earth, at least four satellites "visible" in the sky.
The function of a GPS receiver is to locate 4 or more of these satellites, determine the distance to each one and use this information to deduce its own location. This operation is based on a simple mathematical principle called trilateration. The trilateration in a three-dimensional space may seem a bit complicated, so start by explaining what is two-dimensional trilateration.
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