HOW GPS WORKS | WORKING PRINCIPLES OF GLOBAL POSITIONING SYSTEM WITH EXAMPLE - Anna University Internal marks 2018
What is GPS?
GPS stands for "Global Positioning System". Now it has total of 27 satellites to provide position. Among that only 24 satellites are used and the remaining 3 are in stand by mode. For the working of GPS, it require at least three GPS satellites. The GPS device in your hand will receive signal from 3 or more satellites to find the exact location .GPS works in the basis of triangulation.
Let we see one small example that will help you to understand the positioning concept of GPS.

Example:

Consider that you are standing some where with a map, but you don’t know where you are standing .So you asked a person that "where am I ?" .He said that, you are 200 k.m from Chennai. So you can be any where in a 200 k.m circle. You are a genius so you took the map and drew a circle, say 200c.m.
 Working of GPS - Example
Another person said, you are 150 k.m from trichy. So you drew another one circle. Now the two circles will overlap and you can be anywhere in the overlapped part.
 Working of GPS - Example
The third person said, you are 300 k.m from ooty. And finally you drew another one circle which will give your current position.
 Working of GPS - Example
Like the same, in actual gps system also, the device in your hand will receive signals from 3 or more gps satellites and plot the areas like the above and finds your current position.

 Working of GPS
To find your position the gps unit on your hand and gps satellite should have same time. The gps device has an atomic clock. When your device receives a signal from a satellite, first it will automatically resets its internal clock to the satellites time and then the satellite will transmit a pseudo random code. The gps unit will find your position based on the time it took to reach the gps unit.

Content submitted by:
M.Lordson Roy.
(Bethlahem Institute of Engineering)

To publish your valuable contents in StudentsBlog100 website , mail your contents to "Studentsblog100@gmail.com" .