It’s really tough to find people who use a smartphone but have never used GPS. Google Map is the most popular map if I compare with other, mapping services such as Hear, Apple Maps, WE Go or Microsoft Bing. Let’s discuss tody how GPS actually works.
Think you have lost in a new place you don’t know? There is an online mapping service to help you. Google maps say the distance from the surrounding environment to the distance of the specific destination and the traffic jam situation.
Apple Maps, Google Maps or other mapping services, Uber all are using a magical technology. And that is the Global Positioning System or GPS for short, which if not, you might have found Google Maps – but you couldn’t know exactly where.
To many, the word “Global Positioning System” sounds unfamiliar, but after saying “GPS” I do not expect anyone to look unfamiliar. Some phones also call it “location”. And nowadays, secondary students are also likely to have an idea about GPS because of the new curriculum.
But few people know how GPS works. However, I can guarantee that many people have curiosity. Have you ever wondered how GPS works? The purpose of this post is to satisfy your curiosity.
What is GPS (Global Positioning System)?
Whether or not you judge the merits of the naming, the Global Positioning System or GPS is actually an excellent system. More precisely, it is a system made with at least 24 satellites placed in the orbit of the earth. Of course, there are 3 more satellites as a backup – to avoid any kind of unexpected situation on the space! However, by some estimates, there are 32 satellites in GPS.
These satellites of GPS are not staying together. Rather, they are arranged at approximately equal distances (around 12000 miles in height) around the earth, so that all satellites cover and send signals to every part of the globe (even the deepest part of the Amazon forest). The whole network is set, keeping in mind that you will get at least 4 satellite with you.
Who owns the GPS? Who sent the GPS satellites?
Bangladesh became the owner of its own (Bangabandhu-1) communications satellite last year. There are many countries that do not have any satellite. So who sent such satellites to space for GPS? Who owns them? Google, Microsoft or NASA?
Very good question. Actually, the United States government owns these GPS satellites. Their defense department sent these satellites to space in 1970 for military use. Later in the eighties, they opened these satellites or the entire GPS system for use in all countries of the world or the common people. There are a total of 30 control rooms on Earth for the maintenance of GPS satellites, the main of which is located in Colorado Springs.
Despite previous technology, the common people rarely used GPS. On that time only aircraft, ships, fishing vessels or adventurers used this technology with GPS devices. But after the arrival of the smartphone, the small GPS chip was inserted inside the phone. And now GPS is using extensively in the combination of concepts like Google Map or Uber.
How GPS works?
The GPS chip that you have on your phone is a GPS signal receiver. It can capture signals coming from GPS satellites. This receiver chip does not transmit any information or transmit it to the satellite.
At the starting I mentioned about 24 satellites at the outset, those satellites actually transmit a kind of radio signal 24 hours a day and seven days a week. The GPS chip has the capability to capture that signal on your smartphone or car tracker. Nowadays the GPS chip available in the smartwatch even in the keyring.
GPS satellites have an atomic clock mounted, which gives very sharp time day to day. And you have a clock on your phone. The signals that satellites send are basically the time it takes to send the signal. It calculates the actual distance between the satellite and your phone, regardless of when the signal is received by your phone and when your phone has received that signal. From this distance, GPS basically determines your location
But there is a problem here. The problem is, you cannot position a second object with the distance of one thing to another. To get there, you need to take a distance, at least in terms of three things.
Learn GPS by a game!
An example will clear the issue. Let’s say your friend tells you on the phone that he is 1 kilometer (or more) directly from the Gate of Parliament House. If you listen only to this, you do not know where he really is. Because he could be 1 km away from Parliament House. That means, if a circle of radius of 1 km is imagined around the Parliament building, it can be anywhere along the circumference of the circle.
What if he says that he is staying at a distance of one and a half kilometers from the PM’s office at the same time? Then your position will become a bit clearer to you. Now if you imagine a circle of radius 1.5 km in the center of the Prime Minister’s Office, you will see that this circle intersects the previous circle at two points. That means your friend is on one of these two points. But you couldn’t find your friend’s location yet.
Now if your friend tells you that he is also 500 meters straight from Tejgaon railway station? Then you’re done. Now imagine a circle of radius 500 meters centering the Tejgaon railway station and see that all three circles intersect at only one common point. And that intersection is the Farmgate bus stop. And your friend is actually at the Farmgate bus stop. Isn’t it funny? This calculation is called trilateration.
A combination of GPS and digital maps
However, your GPS does not know the name of your location. It points out your coordinate point. It learns your two-dimensional position through two points, namely latitude, and longitude. You can express every point of the entire earth at some coordinate point. Names of two places may be one, but the coordinates will not be one. After these GPS coordinate points are plotted on a digital map of your phones such as Google Map, Bing Map or Apple Map, you can understand where you are located. This plotting works by mapping apps, such as Google Maps.
GPS also works in this system. Your phone’s GPS chip detects itself at the same distance from the 3-4 GPS satellites. Normally with three GPS satellites signal your location out of your phone as in the example above. This way, the more satellite signals you get, the more your location will be more accurate. This system works best under the open sky because it is convenient to get satellite signals.
Does GPS go without internet?
In fact, there is no obligation on your phone to have an Internet connection to receive GPS signals. You only need the Internet to download a graphical map. So if you download any part of Google Map for offline use then you can see your own location by turning on GPS without internet.
If America Turns Off GPS?
GPS is just a system of location detection. Apart from GPS, there are other alternative methods of knowing the location. But they are not so prevalent, they are not as powerful as GPS.
As I said before, the United States government owns GPS. Although they have made it open to the whole world, they can turn it off if they want (in situations like war).
So Russia has developed a system like GPS which they named GLONASS. Nowadays you can see in smartphone specification Location: A-GPS with GLONASS. This means that the phone can detect a location on both US GPS and Russian GLONASS systems.
Again, mobile phone service companies may know your location based on how far your phone is from a tower. In the same way, location can determine using WiFi network.
Hope this post “How GPS Works” helped you a lot to know how GPS works. Let us know your feedback in the comment section.