WHAT IS GPS :
This is a radio navigation system associated with satellite. Which is operated by United States government. It is a global navigation satellite system. Which delivers geolocation and time information to the GPS receiver. This system is also called NAVSTAR (Navigation Satellite Timing & Ranging).
1973 in Department of Defense U.S. (US) GPS project was launched. And in 1995 it came into operation. This system was not available to the common citizens earlier, it was first used for the Army of the US. So when America made it available to citizens, then its quality was made available by reducing it. Later in May 2000 an accurate GPS system was made available to the public by Bill Clinton.
HOW DOES GPS WORKS :
The Global Positioning System (GPS) is a network of about 30 satellites, roaming in the orbit 20,000 km from Earth.
This system was originally developed by the US government.
Its US Army used for navigation.
But at this time any person can receive radio signal from GPS with the help of mobile or any GPS device.
To make accurate use of GPS, at any time you must have at least 4 satellites 'visible'.
Each of the satellites keeps transmitting signals of its position and current time information at regular time intervals.
These signals travel at some speed. (at light speed)
Your GPS receiver receives the signals, and calculates how far the satellite is based on how long it took for the message to reach the receiver.
Once it is informed that at least 3 satellites are far away from you, then the GPS device can find out what your location is.
And this process is called trilateration.
What is Trilateration
Look at the picture given here, imagine that you are somewhere on Earth, and you know how far you are from satellite A, it means that you are somewhere in the red circle.
And similarly you will know how far you are from satellite B and C.
And where these three circles intersect (meet), there is your location.
It has become a matter of 3 satellites, but the more satellites, the more Accuracy you will be able to know your location.
GPS USES :
- Location (to know your location)
- Navigation (to move from one place to another)
- Tracking (to track something or a vehicle)
- Mapping (to map the world)
- Timing (to know the exact time)
0 Comments