Informative Essay

How does a GPS work?



Have you ever thought about how a GPS works?   I was on a trip with my friend and she had one that she was using for directions.   It is an expensive, light weight, small, square shaped, and has fancy little pictures on the screen.   It also has an annoying little voice that talks to you while you are driving so you don’t have to be distracted by looking at it every two seconds to see where you have to turn.   Above is a picture of a GPS to show you what it looks like.   I thought it was the best thing that was ever invented.   So, I decided to do research on how they work.

A GPS is also know as Global Positioning System and is used for navigation.   Before GPS systems were invented people used compasses and maps
to navigate for hundreds of years.   In the article Brain and Harris wrote they stated that a GPS is made up of 27 Earth-orbiting satellites (howstuffworks.com).   The military developed the GPS for military navigation, and then the government opened up the satellites for civilian use in the 1980s.   A GPS receiver will tell you where you are and provide you with a route to your destination.   These days a GPS will provide directions, maps, traffic, weather, and points of interest.

Brian and Harris also stated that a GPS works by locating four or more satellites to gather information.   The information the device needs to gather is the location of the satellites and also the location of the device to determine the distance.   How this works is through a mathematical method called trilateration.   This method calculates your exact position also it can tell you how fast you are going and how long it will take you to reach your destination.   GPS receivers are very accurate on the calculations it makes (how stuff works.com).


This is a picture of the GPS satellites that orbit the Earth.

The basic GPS comes preloaded with maps that work from the information provided from the satellites.   You can download updated maps or... [continues]

Read full essay