Communication Devices in The 21st Century

GPS Systems and How They Work

Having an understanding of how GPS systems work will make you more appreciative of their complexity and make you less likely to balk at the cost.  GPS systems are added – and more often, standard – features in the latest cars, PDAs (Personal Data Assistants) and cell phones.  The succeeding paragraphs will endeavor to provide a simple overview of how GPS systems operate. If you need a more technical explanation, there are other articles on the web that address that.

The ABCs of GPS

Encircling our planet right now, you will find about 2500 satellites.  Not surprisingly, GPS satellites account for a great percentage of these.  I know that sounds impressive, but only about 36 of them are actually in operation. A large number consists of retired GPS satellites.  They constantly send a low-power radio signal to Earthly GPS receivers (not the other way around).  By obtaining a signal from three of these satellites, a GPS is capable of measuring the distance from each and determines a position based on that data.

GPS systems satellites are about seventeen feet across when their solar power panels are fully expanded.  They run on solar power and as extra insurance have backup batteries installed.  They generally survive ten years or longer if all goes well. The earliest satellite is from 1978.  That one goes around telling all the junior GPS satellites how challenging it was in his day and how easy the younger ones have it. Just a little satellite humor there.

But Seriously

So what devices qualify as GPS receivers?  It’s basically any device that is able to receive signals from GPS satellites.  There was in all probability a GPS receiver on that cruise ship you were on last summer, another in the taxicab you took to the airport last week and then there’s that Navigon 7100 GPS that your boss just bought for his car.  Portable GPS systems for public use are averaging around $300, give or take a few dollars.  Considering you didn’t have to pay to design and launch the satellite into space, $300 is a fairly reasonable price.

It’s the US government who picks up the tab for constructing the satellites and launching them into space. Your only job is to turn on your GPS system and enjoy the benefits it brings you. Hopefully now you have a better understanding of how your GPS system works the next time you switch it on.

and is filed under GPS. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.