How does a GPS Module Work

GPS is everywhere! You have probably used and benefitted from GPS. They are found in most of the smartphones, many new automobiles, and now even in smartwatches. It helps you to get where you want to go. These tiny devices can give your position and time simultaneously almost anywhere on the planet.

But what is GPS? In this guide, we will give an insight into what is GPS, how it works, and what are the applications of a GPS module.

What is GPS

GPS (Global Positioning System) is a satellite-based navigation system. It provides time and location-based information to a GPS receiver, located anywhere on or near the earth's surface. GPS works in all weather conditions.

The satellite system consists of a constellation of 24 satellites in six Earth-centered orbital planes, each with four satellites, orbiting at 13,000 miles (20,000 km) above Earth and traveling at a speed of 8,700 mph (14,000 km/h).

While we only need three satellites to produce a location on earth’s surface, a fourth satellite is often used to validate the information from the other three.

The GPs modules have become small over the years. These modules have tiny processors and antenna that receive data sent by the satellites and compute your position and time.

Working of GPS

GPS works through a technique called trilateration. Trilateration is the process of determining your position based on the intersection of spheres. When a receiver receives a signal from one of the satellites, it calculates its distance from the satellite considering a 3-D sphere with the satellite located at the center of the sphere. Once the receiver does the same with 3 other GPS satellites, the receiver then proceeds to find the intersection point of the 3 spheres to calculate it’s location. Used to calculate location, velocity, and elevation, trilateration collects signals from satellites to output location information.

The GPS module receives a timestamp from each of the visible satellites, along with data on where in the sky each one is located (among other pieces of data). From this information, the GPS receiver now knows the distance to each satellite in view. If the GPS receiver’s antenna can see at least 4 satellites, it can accurately calculate its position and time.

A single satellite broadcasts a microwave signal which is picked up by a GPS device and used to calculate the distance from the GPS device to the satellite. Since a GPS device only gives information about the distance from a satellite, a single satellite cannot provide much location information. Satellites do not give off information about angles, so the location of a GPS device could be anywhere on a sphere’s surface area.

When a satellite sends a signal, it creates a circle with a radius measured from the GPS device to the satellite.

When we add a second satellite, it creates a second circle, and the location is narrowed down to one of two points where the circles intersect.

With a third satellite, the device’s location can finally be determined, as the device is at the intersection of all three circles.

Applications of GPS

GPS is a powerful and dependable tool for businesses and organizations in many different industries. Surveyors, scientists, pilots, boat captains, first responders, and workers in mining and agriculture, are just some of the people who use GPS on a daily basis for work. They use GPS information for preparing accurate surveys and maps, taking precise time measurements, tracking position or location, and for navigation. GPS works at all times and in almost all weather conditions.

These are the main uses of GPS:

1. Location — Determining a position.

2. Navigation — Getting from one location to another.

3. Tracking — Monitoring object or personal movement.

4. Mapping — Creating maps of the world.

Parameters for Selecting the Right GPS Module

1. GPS Pulse Accuracy

This is the accuracy of the 1Hz pulse received from the GPS module or chipset.

2. GPS Sensitivity

The minimum level of the signal that allows a GPS receiver to acquire or track the GPS signal.

3. Acquisition sensitivity

Minimum level to successfully get GPS signal information while the system powers up the first time.

4. Tracking sensitivity

Minimum level to maintain location fix once it has been attained

5. Interface Type

When we use any GPS chipset or GPS module, then over some interface, we need to get the GPS packet information. That interface could be UART, I2C, SPI, etc.

6. Operating Supply Voltage

This is the voltage over which the GPS module or chipset works.

7. Operating Temperature Range

If using a GPS module for outdoor applications, then the minimum and maximum operating temperature range shall be checked.

This I hope you have learned about how exactly a GPS module works and what all things are required to keep in mind while buying a GPS module.

GPS with Antenna is the best GPS module you can get today. See more of these GPS modules as they are also compatible with Bluetooth. GPS with a compass is also a trending module of various GPS modules that can give you the exact position with 95% accuracy. Know more about these GPS modules.

Drone Frames is the one crucial component that keeps the GPS module safe while the drone is in the air. If you want to know more about the selection of Drone Frames Click Here.

Explore more such GPS modules and build your own project with it.

This blog was written in reference to the blogs published by Sparkfun and electronicwings.com