Origins of GPS

GPS stands for Global Positioning System, the world’s first man-made satellite navigation system. It was launched in 1978 by the US Department of Defense. During the cold war, GPS was used primarily for military purposes.

After the Korean Air Lines Flight 007 was shot down in 1983, President Ronald Reagan issued a directive making GPS available for free for civilian use, specially, for the aviation industry.

By 1996, President Clinton authorized Selective Availability phased out in NAVSTAR (Navigation Satellite Timing and Ranging), the official US government name for GPS. Selective Availability was used to limit GPS accuracy for civilian users. With Selective Availability out, civilians can now achieve 10 to 15 meters accuracy, compared to the previously available 100-meter accuracy. This is a major win for the manufacturers and marketers of GPS devices.

By the way, there is no set-up charges or subscription fees to use GPS! A GPS device receives signals and information transmitted by 24 satellites. They are arranged in their orbits that allow a GPS device to receive at least 4 signals at any given time. They are then turned into more user-friendly calculations in terms of latitude/longitude or location on a map, and then displayed on to the device.

My first experience with a hand-held Garmin GPS was last January, when my cousin, Ben Velez, lend me his unit while Cecile and I were going around the Big Apple. Yes, it was helpful and help get us to shopping places. Yes, technology works!

Photos courtesy of Google Images.

Please check my whole column (Meet Magellan) at
http://www.manilatimes.net/national/2008/jan/07