October 11, 2012 by Nakul
Author: Shahbaaz Ahmed
Tracking anything and anyone was not an easy task without GPS. It is used by people to judge their locations in a digital frame. For most equipment, the accuracy is 100 to 10 meters .In a GPS system there is a space segment consisting of 27 satellites orbiting the earth(of which 3 are spare) ,the user(device to be tracked) and the control segment that consists of various devices for tracking.
The positioning is done by calculating the time taken to receive a signal from satellite to the user and back to the satellite .The satellites are placed in such a way that at any time there are four satellites above the horizon for any point on earth .Each satellite is designed in such a way that it continuously updates the changing position by itself .On the ground the user who is under the watch of three to four satellites bounces back the signals once received to all the satellites from which it had received signal then the result is provided in terms of longitudes and latitudes for the receivers(control segment) usually within 100 meters.
If all the 4 satellites signals can be received the receiver can figure out altitude as well as the geographic position. GPS system may also be used for the measurement of speed in cases where the user is moving.
To obtain the data more accurately more than one receiver are used and the data obtained is transmitted to the GIS (geographical information system). GIS is a computer based software capable of handling the various details on the receiver. GPS finds wide applications in each and every sense of life. One such application is tracking of mobile phones .GPS is very useful for tourists. Although maps are available, GPS is a live map which would be more accurate than an old printed one.
There are both 2d and 3d systems available in a GPS system .There are even attempts made for the further improvement such as GPS IIR(M), GPS IIF, and GPS III,including next generation operational control system(OCX). Overall the impact global positioning system has brought in modern technology is a magical one.