No-one would have thought a century ago that, people of the future will be able to find their exact location on an unknown location without paper maps? Well, this tech revolution century certainly had made it possible. The name of the technology is GPS – Global Positioning System. I know all of you are familiar with this term. From your electronic device in the pocket to your mechanical cars, everywhere there is a huge application of GPS.
What is GPS?
GPS or Global Positioning System is a navigational system that is dependent on satellite signals to show an object’s location. GPS works by receiving signals from satellites orbiting the earth.
History of GPS
Have you heard about Doppler Effect? I hope yes. If not then let me explain to you in a nutshell. Suppose you are an observer, you are moving relative to a wave source, then the changing in frequency, and wavelength of the wave in accordance with the observer is Doppler Effect.
Now your question is that what Doppler Effect has to do with GPS Tracking? Well, it was the beginning of the GPS generation. In the Sputnik era, scientists were able to track the satellite with shifts in its radio signal using this Doppler Effect. In 1960, US Navy conducted satellite navigation experiment to track US submarine carrying nuclear missiles. However, in 1970, the Department of Defense (DOD) wanted a stable navigation system. Taking the concept from US Navy, DOD Launched its first navigation system satellite (NAVSTAR) in 1978 consisting of the 24-satellite system. However, the network was completely open to the public in the year 2000.
Let’s move forward and talk about the tracking process of GPS.
How does GPS work?
GPS system needs a minimum of 24 satellites for functioning, placed 12500 miles from the surface of the earth. Each satellite orbit the earth twice a day. However, let me tell you GPS is the navigation system of the USA consisting of 31 satellites. Similarly, the navigation and positioning system of other countries are India-NavIC (7 satellites); Russia-GLONASS (24 SATELLITES); China-BeiDou (22 satellites); European Union-Galileo(14 satellites). Therefore, the total 98 active satellites are orbiting the earth for navigation and positioning systems. However, to determine your location minimum of 3 satellites are required to be within radio contact above our horizon no matter where u are. Why 3 satellites? This is because of Trilateration.
What is Trilateration?
GPS receives signals from these 3 satellites letting you know where you are. Suppose the 3 satellites are named A, B & C.
Suppose satellite A can transmit signal within this circular range. But the receiver may not be in this range, they can be anywhere in the earth. Satellite B then come into use with its transmission range. But it’s still not accurate.
To become more sure we use the transmission range of third satellite C. The intersection of the range of these three satellites, tells the exact location of the receiver.
Come let ‘s get the real view.
However, you can see there are two regions of intersection. The first point-1 is in space. So except the astronauts, there is no possibility of the receiver to be present there. The second intersection is point 2 i.e. on earth. The full possibility of yours to be present there. These three satellites help to calculate the latitude and longitude. Other satellites can also come into play, i.e the fourth satellite to calculate the altitude. This is all about trilateration.
Nevertheless, this is not the end. GPS satellites don’t know the distance of the receiver. They just broadcast their own location and their current clock time. The clock time frequencies are made to run slower in the satellites because we know from the theory of relativity that farther we go from the earth surface faster the clock runs. This clock time frequency is monitored by the team in the base stations on earth.
The satellite transmits these signals in the form of radio signals, traveling at the speed of light. The receiver receives that clock time signal compares with its own time, then calculate the time delay and find the distance of the satellites from where the signal is being transmitted. Now calculating all the circular distances of the satellite, knowing the exact location of all the satellite will give us our own location.
So this was all about how GPS system works and how can we locate an object with the help of GPS system.
This tracking is done either by a GPS TRACKER which is a device or by an application like Google Maps in your mobile which locates with the help of cell phone towers. If it fails then only it activate the GPS.
GPS tracker is a device which runs on battery source with the help of a SIM card. This GPS tracker has a wild application in wildlife, law enforcement, protect kids, theft prevention, aircraft, military and many more. It can tell the exact location of the object or its past records. Moreover, it can also tell the speed of the object. It gives real-time access as well it keeps the past record. It can be monitored using the software.
However, GPS satellite services are free to use. Everyone use this free service and locate things & objects. But very few know the actual working of a GPS system. Eckovation is happy that u are eager to know about the GPS Tracking process. We will keep bringing this kind of interesting topics that you will be interested to know and share among others.
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