GPS stands for Global Positioning System that provides location, velocity and time synchronization based on a global satellite system.
We all heard of GPS at some point. Nowadays, GPS is everywhere and is being used in most of the modern applications that we use daily, such as smartphone and smartwatch.
It is a crucial technology that shapes the future and helps function multiple industries all around the world. Some businesses are more depended on it than others.
In this article, we will explain you what the GPS stands for and how the GPS technology functions.
What is GPS?
Global Positioning System (GPS) is a satellite-based navigation system that tells you where you are on Earth. GPS provides people with current positioning, navigation, and time services.
The purpose of GPS is to navigate us through one place to another. Global Positioning System is a free service that is owned and operated by the U.S. government.
Global Positioning System (GPS), originally Navstar GPS consists of three main segments: space, control and user segment.
Space segment – It consists of 24 satellites that transmit one-way signals that provide current GPS position and time of the satellite.
Control segment – It consists of monitoring and controlling stations that ensure of correct satellite behaviors, maintain health and status of the satellite constellation.
User segment – It consists of equipment called receiver that receives signals from the GPS satellites and calculates the user’s dimensional position and time.
There are several use cases of GPS, as well as multiple factors that influence the accuracy of GPS. Continue reading to find out more about it.
How does GPS work?
The whole satellite system consists of 24 satellites travelling around the globe. Those 24 satellites are located in 6 orbital planes, where each orbital plane consists of 4 satellites. Only 3 satellites are needed to produce a location on Earth, but 4th satellite is used to validate the accuracy of the information.
GPS works based on a technology called trilateration. Calculating location, velocity and elevation, trilateration collects signals from satellites to provide location information.
The information from satellites is defined by the GPS device. In order to calculate the location, the device needs to be capable of reading the signal from at least 4 satellites.
Each satellite in the network circles the earth twice a day, which means that a GPS device can read the signals from six or more satellites. Each satellite broadcasts a microwave signal, which is obtained by a GPS device (receiver), which then calculates the distance from the GPS device to the satellite.
When a satellite sends a signal, it doesn’t give a precise information, but creates a circle with radius, based on the measured distance from the GPS device to the satellite. By adding second satellite, we will have another circle, which creates two points where circles intersect. The third satellite creates another circle, which helps to determine the device’s location.
In other words, we live in a three-dimensional world, where satellites produce spheres instead of simple circles. Where three spheres intersect, the two points provide a precise information and the nearest point to the Earth is chosen as a final position. See the visual explanation below.
Key findings of GPS
These are the key findings of GPS:
- GPS stands for Global Positioning System
- Helps millions of people navigate everyday
- It consists of 24 orbiting satellites
- Owned and operated by the U.S. government
- Each GPS device can read the signals from six or more satellites
What is the GPS used for?
GPS has multiple use case variations. It is a very powerful tool that many businesses and industries could not simply function without it, such as Police & First Responders, Transportation, Construction, Mining and more.
GPS is typically used for:
Location: establishing a position
Navigation: Getting from point A to point B
Tracking: Monitoring of physical assets or people
Mapping: Building world maps
Timing: Making time measurements more precise
There are several factors that influence the accuracy of GPS, such as the number of satellites available, urban environment, the ionosphere and more. To go more in depth, common problems occur because of surrounding mountains, buildings, trees, heavy storms happening nearby and more.
The GPS accuracy has gotten way better than it used to be a couple of years ago and we expect it will only grow in its accuracy and reliability.
GPS is a crucial aspect in fleet management, as the units, drivers and fleet managers rely on precise vehicle data and positioning. AutoPi Asset Tracking solution is also quite dependent on the global positioning system.
The U.S. government made GPS publicly available in 1983, limiting users to control all data. Since 2000, general public has gained full access to the use of GPS.