Gone are the days of pulling over to the side of the road to locate and unfold a map the size of Rhode Island. GPS has become a household term, one that even preschoolers likely understand. It helps you get from Point A to Point B without having to perform illegal U-turns or (worse yet) stop to ask for directions. It's available in our cars, on our phones, and in our school buses. It has become a necessity when traveling, one that we likely take for granted.
What is GPS exactly?
GPS (Global Positioning System) is a space-based satellite navigation system that provides location and time information. And it can accomplish all that despite weather conditions. That's right...if you are anywhere on or near the Earth (which most of us usually are) where there is an unobstructed line of sight to four or more GPS satellites, you can be located. It's a pretty amazing technology.
How does it work?
It's all about satellites. A GPS receiver calculates its position by precisely timing the signals sent by GPS satellites high above the earth. Each satellite continually transmits messages that include the time the message was trasmitted and the satellite position at the time of message transmission. The receiver uses the messages it receives to determine the time of each message and compute the distance to each satellite using the speed of light.
Where did this amazing technology come from?
Not surprisingly, GPS stemmed from the government, as it has been used to provide critical capabilities to military, civil and commercial users around the world for years. In fact, GPS was developed in 1973 to overcome the limitations of previous navigation systems. (Prior to that time, the Pentagon launched TRANSIT, a system of more than a dozen satellites creating the first positioning system for the Navy.) The U.S. Navy and Air Force combined their navigation systems to create a Defense Navigation Satellite System (also known as NAVSTAR), which became the GPS system we know and use today.
Thus, GPS was created and realized by the U.S. Department of Defense and was originally run with 24 satellites. (Bradford Parkinson, Roger Easton and Ivan Getting are credited with the invention.) It became fully operational in 1994, but the government put it under Select Availability as a security measure, preventing other countries from receiving the information.
The U.S. Government ordered the military to stop scrambling select data from the Department of Defense satellites in 2000. This change made the data freely available to the public, and entrepreneurs took it from there.
By 2007, the U.S. Government announced plans to eliminate Select Availability altogether by building GPS satellites without it. In 2010, the U.S. Air Force implemented a new 24 3 GPS configuration that improves satellite visibility and decreases loss of service.
For consumers and the economy alike, GPS has been a huge win. According to a recent article in the Harvard Business Review, GPS has added approximately $90 billion in value to the U.S. economy in 2011 alone. (Wow!)
So, the next time you use your smartphone to access coupons from nearby grocery stores or have your runner's watch lead you on a new route back home, you can thank the U.S. Department of Defense - and the Clinton administration for helping GPS become a household brand name.
(Infographic Credit: BrickhouseSecurity.com)