What is GPS? - A Brief History and Breaking Down How GPS Devices Work

14 minute read

GPS, or Global Positioning System, is truly one of the most fascinating inventions in the world. 

Regarded as one of the most helpful, if not essential, devices in modern history, GPS as we know it has gone through a lot of improvements before becoming the crucial, wayfaring technology that we use today.

We won’t linger explaining the scientific details and bombard you with technicalities. Instead, we’ll break down the important questions without oversimplifying the science behind GPS and its features and functions.

In this guide, we will discuss what GPS is, how this technology came to be, how it works, and everything a regular driver and traveler needs to know about GPS, including important uses.

What is GPS? - A Brief History

GPS is mainly used for tracking a vehicle’s exact location, speed, and trajectory, as well as for navigating airplanes, ships, cars, trucks, and other vehicles.

We use GPS technology all the time but rarely do we ask ourselves who is responsible for this scientific contribution and how did they come to it. Before we go into details, let’s review some historical facts.

In the 60s, the U.S. Department of Defense paved the way to this new technology. Their staff of scientists developed the functional GPS or Global Positioning System, which was ultimately developed to assist the US military at the time.

Still, nothing would be accomplished today if it weren’t for the groundbreaking discoveries of a great 17th-century thinker.

What is GPS? - Sir Isaac Newton’s Posthumous Contribution

Science hotshot, apple enthusiast, and an all-round gentleman, Sir Isaac Newton was the first to doubt the Earth’s “perfect” sphere. It was the late 1600’s and he believed that our planet was an elliptical shape, or “slightly oval”, a statement which indirectly shaped the fundamentals of GPS, among other things.

The fact that the Earth wasn’t perfectly round, meant that the center of mass would be very difficult to find. Oval shaped forms require a lot of calculations and it was pretty complicated to get to the bottom of this, and that’s why the scientists of the past could only approximate the center.

Let’s just say that, if the earth is truly round, the satellites would have had easier jobs and simple trajectories to find, and ultimately GPS tracking would have been a whole lot easier. But, it doesn’t work that way.

Let’s take it even further back - Ptolemy. An Egyptian.

Known for his geocentric model of the cosmos, he believed that the movement of the heavenly bodies could be presented in mathematics. Ptolemy's earliest recorded works are on geographical position, and more importantly, he was the first to describe the idea of latitude and longitude.

There were some crucial observations and geometry research from the Chinese civilizations, as well as the Arabs and Byzantines who made some astounding discoveries. But Ptolemy was the first to understand and point out that to describe a sphere, one must figure out the radius and center point. Newton still needed to calculate and specify a center point when he learned that the radius to the poles was shorter than the radius to the equator of the earth.

The Byzantines and Arabs carried this knowledge through to the modern era, and there were Chinese observations to add to these works.

Besides the “how big is the Earth?” question, this has been one of the bigger mathematical problems that have been dizzying the greatest of minds throughout the ages.

What is GPS? - Sputnik, the Doppler Effect, NAVSTAR, and the World Geodetic System

Now let’s fast forward to the 60s.

GPS has its origins way back in the era when the first Sputnik, along with other satellites that were sent to orbit, was used by scientists to calculate their movement via a specific range finder, as their exact trajectories were affected by gravity.

The scientists were able to pinpoint the satellite’s movement with the help of small radio signal shifts also known as the Doppler Effect. In the 60s, the US Navy used this type of satellite navigation experiment to pinpoint submarines that carried nuclear weaponry. The method was so efficient, they could pinpoint the exact location within just a matter of minutes!

The Department of Defense, way back in the 70s, vouched for the design of a better and more stable satellite system, capable of worldwide navigation. The research gathered by the Navy scientists ensured the creation and improvement of the navigation system.

The 24 GPS Satellites Orbiting the Earth

The reason why GPS still remains as one of the most brilliant designs of ingenuity, is because somebody thought it was a good idea to navigate our ways with the use of satellites.

The first constellation of 24 satellites was launched in 1994, but before that occured, the first-ever GPS satellite was launched in 1978, just 5 years before Reagan authorized the modernized usage. The GPS satellites are referred to as NAVSTAR, all thanks to Bradford Parkinson. We will discuss his contribution to GPS technology later on.

From their findings, the Earth’s center of mass showed a precise location in relation to multiple points that are placed on the Earth’s surface.

The GPS use of these satellites relied on something called a trilateration system since GPS uses the three main factors of latitude, longitude, and altitude.

With the timed information, the receiver, or the GPS device, determines the user’s location and also calculates other measures like distance from A to B, trip duration, calculating the shortest path, heavy traffic areas, roadblock updates, etc.

After finalizing some projects, the Department of Defence finally launched NAVSTAR, or the first Navigation System with Timing and Ranging satellite, in 1978.

Afterwards, in 1984, we reached a general consensus to simply call the newfound system - ‘The World Geodetic System’. That year the world finally agreed on a specific center point that is today used by everyone.

These features also depend on the manufacturer of the GPS device, but we can safely say that a large number of GPS devices are fully updated and designed for ease of use and exceptional services.

There are GPS tracking devices with exceptional quality. Today, you’ve got sports wristwatches and devices that can do all kinds of stuff.

From then on, it has been way easier, and from that specific point, we can define the paths of satellites, and we can also approximate the spherical parameter of the Earth.

Scientific achievements aside, there’s still a certain lack of agreement over the question of who should be rightfully credited with the conception of GPS.

The People Involved in the Conception of GPS Technology

There have been several names of important scientists who are frequently mentioned as direct progenitors and contributors like Roger L. Easton, and Ivan Getting, crucially involved in the engineering and development of GPS.

At least three or four people are recognized as the crucial inventors and associates of the legendary project. But we can say for sure that Bradford Parkinson, an Air Force colonel at the time, is regarded as the chief architect of the Global Positioning System throughout the technology’s conception.

Parkinson was put in charge and assigned to revive an old military program called the 621B Space and Missile Systems Organization. Reportedly, the program provided altitude, latitude, and longitude for military navigation purposes. The original deployment of GPS was supposed to be a successor to the PNT (positioning, navigation, timing) requirements for the vehicles at the time.

Dr. Gladys West

We would also like to mention Dr. Gladys West, as one of the key figures in paving the way for the modernization of GPS technologies. Her recognition as an important contributor has been long-awaited, and disputed, mainly because of socio-political reasons.

A mathematician by default, she started working in 1956 in the United States Naval Weapons Laboratory, at the forefront of the Cold War space race era. Her job mainly involved a big part number crunching, data processing, as well as conducting extensive research on satellite navigation.

Dr. West was inducted into the Air Force Space and Missile Pioneers Hall of Fame in December 2018. She is responsible for programming an IBM 7030 computer to “deliver increasingly refined calculations for an extremely accurate geodetic Earth model, a geoid, optimized for what ultimately became the Global Positioning System (GPS) orbit” with the Air Force recognizing her contribution at the awards.

Ronald Reagan and Popularization of GPS

Initially, only the US military had access to GPS technology. The usage of GPS tracking underwent modernization as soon as President Ronald Reagan authorized it in 1983 after more than 250 people died on a Korean airliner after being brought down by Russian airplanes.

The tragedy was ruled an accident because the plane mistakenly went on course into Russian airspace. This prompted an immediate action, and President Reagan was the first to ‘greenlight’ GPS technology for civilian use.

GPS slowly but surely became a worldwide technology, used by many for navigation, and today there are 32 operational satellites on GPS duty. Today, GPS is used for more civil and commercial uses, as a multi-purpose, satellite-based radio navigation system that makes things easier for us all.

What is GPS? - How does GPS Work?

Here’s a TL;DR - there are 24 satellites that send info to the GPS device in your car so that your exact statistics regarding location, trajectory, and speed appear on the screen.

A unique system, the GPS uses microwave signal transmission from these 24 satellites orbiting the Earth. They pinpoint a receiver’s exact location, speed, and trajectory of movement.

Every satellite sends these signals and parameters so that the built-in GPS device on your car decodes the output and calculates the location of the satellite. The GPS receiver measures the exact distance to every satellite and calculates the amount of time it takes for the signal to reach the destination.

Surprisingly enough, less than 50 watts are needed for the transmitter to send signals, but GPS satellites also use solar energy and have backup batteries, in case of a solar eclipse!

Sometimes the GPS signal is blocked or delayed, and the technology is still being updated to perfection. This may happen on various occasions and instances. This includes factors like the atmosphere, tall buildings/tunnels, clock errors, orbital location errors, satellite reading errors, geometry shading, etc.

For more on GPS tracking devices and details of use, please refer to our guide here.

Does GPS Work Indoors?

GPS does NOT work well indoors. The signal still reaches the destination, but just barely, and that’s not enough for proper coordination.

While today’s GPS technology has reached new heights, and today’s more sensitive devices are able to receive the satellite signals with no problem, it’s still not accurate enough for the device to pinpoint the location.

Because of the thickness of the walls, and/or interception from other objects, the GPS signals are scattered and some fail to reach their destination.

Sometimes the error margin (in distance) of the GPS navigation systems is greater than the space itself, and this can cause many problems and miscalculations.

GPS Car Navigation Systems

The GPS devices that we’re using now are the GPS car navigation systems.

Some GPS devices combine the tech from satellites with interactive built-in maps and travel routes, and there are some products that can be updated with traffic information and interactive routing.

These GPS devices are also famously known for their automated voice activity, guiding your every turn. It’s usually a woman’s voice, and it’s designed to be quite calming.

Having to stare on your screen is dangerous. That’s why GPS devices have an automated voice control that instructs and navigates you while you keep your eyes on the road.

Staying Updated

There are GPS car navigation devices with system updates and data plans[c], under a certain manufacturer’s subscription.

The world is constantly changing, businesses come and go, new roads pop up, points of interest appear, gas stations, etc. This is why we need to have updates that are constantly maintained via GPS software and map updates.

Weather is also an important factor in GPS software. New GPS devices are in sync with the newest weather forecast applications and they keep you well informed. This is a very important feature which could prevent traffic accidents.

What Is GPS? - How Accurate Is It?

Today's GPS receivers are sophisticated enough to be very accurate, and this is owed to their multi-channel design, which almost instantly locks on to the location statistics.

Most GPS receivers maintain a tracking lock and have specific settings built for big cities, and this means areas where tall buildings are present. Tall buildings tend to affect some signals here and there, and this is why there are GPS receivers with pre-made settings, specially designed for cities. Goes without saying, GPS devices for ships are far more accurate - they’re out in the open seas!

The scientific community is constantly working on new ways to further improve the precision and accuracy of GPS technology. Today’s regular GPS receivers offer 10 to 15 meters of accuracy. Military-grade GPS devices that go up to tens of thousands of dollars can be even more accurate.

GPS Trackers Are Accessible Now More Than Ever

There are some correctional information software for GPS devices that are available which can improve accuracy up to one to two meters.

The software uses a process called DGPS (differential global positioning software), and it uses a second receiver at a static location to calculate specific points and correct the GPS measurements.

The subscription services for this are pretty expensive, but all in all, you don’t really need those two meters. There are brilliant GPS tracking devices that work perfectly, and won’t cost you a fortune.

The Commuter Hardwired GPS Tracker does the job just right, as well as The Recon 4G LTE Real-Time GPS Tracker, that boasts the best coverage in the USA. The tracker has real-time updates that tick every 10 seconds, so you won’t have to worry about accuracy or battery life. 

The Outlander Portable Real-Time GPS Tracker is a great choice too. If you have any questions, feel free to contact us.

If you are looking to buy a GPS tracking device, please read our guide to GPS trackers [e]so you know which features you need to keep your eyes on.

Final Words on GPS Technology

GPS has become a truly inseparable part of modern life. You can say that we’re almost dependent on its services.

Throughout modern times, it slowly crept up, as we use it mostly while driving and traveling. Even our cell phones use location services that are also dependent on satellites, which, in turn, are mainly used for GPS technology.

The idea behind this guide is clearing up important questions regarding GPS as well as explaining how it came about. The thing is, we use it, but we don’t know anything about it. This guide will help you solve that problem and fully explain to you what is GPS.

Compared to the early predecessors, today's GPS devices are quite compact and extremely accurate. As a global village, our destination has always been scientific progress. Thanks to the contributors, struggles, hard work, and the general-purpose, we now freely use GPS navigation systems to safely get to our own destinations.

For more information about our GPS tracking devices, please contact us at any time!

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