What is GPS ?/Elements of GPS / Its uses / How does its work /

 What is GPS ?

Global Positioning System;(GPS), formerly known as Navstar GPS, is a satellite navigation system owned by the U.S. government and operated by the U.S. Space Force. It is a type of Global Navigation Satellite System (GNSS) that can provide geolocation and time information to GPS receivers anywhere on or near the earth, where the sight of four or more GPS satellites is not obstructed. Obstacles such as mountains and buildings can block relatively weak GPS signals.

Three elements of GPS 

GPS is made up of three different kinds of component, which are also known as segment,

Which work together and give information and location.

1. Space (satellites) - Satellites orbiting the earth send signals to users about geographic location and time of day.

2. Ground control -  The control section is composed of a ground monitoring station, a main control station and a ground antenna. Control activities include the monitoring and operation of space satellites and transmission monitoring. There are measuring stations on almost every continent in the world, including North and South America, Africa, Europe, Asia, and Australia.

3. User equipment -  GPS receivers and transmitters, including clocks, smart phones, and telematics equipment.

How does GPS work ?

GPS use  a technique called trilateral surveying. Trilateration is used to calculate position, speed, and altitude, and collect signals from satellites to generate position information. It is often confused with triangulation, which is used to measure angle rather than distance.

The signals sent by satellites orbiting the earth are read and interpreted by GPS devices located on or near the surface of the earth. The GPS device must be able to read the signals of at least four satellites to calculate your location.

Each satellite in the network orbits the earth twice a day, and each satellite broadcasts a unique signal, orbital parameter and time. GPS equipment can read the signals of six or more satellites at the same time.

Satellites emit microwave signals, which are received by the GPS device and used to calculate the distance from the GPS device to the satellite. Since GPS devices only provide distance information from one satellite, a single satellite cannot provide an accurate location. Satellites do not transmit angle information, so the position of the GPS device can be anywhere on the surface of the sphere.

When a satellite sends a signal, it creates a circle whose radius is measured by the GPS device to the satellite.

When we add a second satellite, it creates a second circle, and its position shrinks to one of the two points where the circle intersects.

Finally, with the aid of the third satellite, you can determine the location of the device because it is located at the intersection of the three circles.

However, we live in a 3D world, which means that each satellite forms a sphere, not a circle. The intersection of the three spheres produces two intersections, so choose the point closest to the earth.

As the device moves, the radius (distance to the satellite) changes. Changing the radius will create a new sphere, giving us a new position. We can use this data in conjunction with satellite weather to determine speed, distance to destination, and estimated time of arrival.

What are the uses of GPS ?

GPS is a powerful and reliable tool for companies and organizations in many different industries. Investigators, scientists, pilots, captains, first responders, mining and farm workers are just a small number of people who use GPS every day. ... They use GPS information to create accurate maps and surveys, make accurate time measurements, track location or location, and navigate. GPS can always work in almost all weather conditions.

> Most common uses of GPS 

1. Tracking - Equipping your company’s vehicles with a GPS vehicle tracking system is a great way to track vehicles and their employees. This not only contributes to the safety of employees, but also enables them to handle company values ​​responsibly.

2. Location - GPS technology provides you with the easiest way to reach your destination. You can also easily set the current coordinates and share with your contacts. This is easier than using a map to find the location. The same is true for vehicles using GPS vehicle positioning systems, which is useful when GPS vehicles are stolen.

3. Navigation - With GPS devices, navigation becomes easier. Provide important information, such as the distance to a specific location and the shortest route. Based on the GPS map, you can view and travel based on topographic features.

4. Mapping - creating maps of the world.

5. Timing - Allow accurate time measurement.

History of GPS 

For thousands of years, humans have used the sun, moon, stars and later sextants to practice navigation. GPS is an achievement achieved by space age technology in the 20th century.

GPS technology has historically been used all over the world. The launch of the Russian Sputnik 1 satellite in 1957 opened up the possibility of geolocation, and the US Department of Defense soon began to use it for underwater navigation.

In 1983, the US government provided GPS to the public, but it is still tracking the available data. It was not until 2000 that companies and the public could use GPS, which eventually paved the way for the further development of GPS. ...