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Getting There: GPS continues to guide the way

December 17, 2018

Why do men have a reputation for never asking for directions, even when they’re lost? Is it because they’re macho, or just don’t like maps? Why do we enjoy the hunt over finding the prize?

Technology has made that debate moot with the invention of GPS — the Global Positioning System.

The history of GPS isn’t that old, but it is fascinating.

In 1973, the U.S. Department of Defense launched the first of a fleet of 31 satellites circling 12,550 miles above the globe. Each satellite has a built-in atomic clock, synchronized with the ground station and the other satellites. The satellites constantly transmit data about their time and location and GPS “receivers” (in your car and phone) pick up the signals from at least four satellites to compute your location.

The GPS system was initially only for military use. But after Korean Airlines flight 007 was shot down for straying into Russian airspace, President Ronald Reagan issued an order making the system available for civilians.

In 2000, President Bill Clinton enhanced the order, making GPS even more sensitive to your exact location. The most accurate GPS receivers (used on aircraft) can now pinpoint your location to within 3.5 meters.

That’s when commercialization took off, though the first portable GPS receivers weighed 1.5 pounds, could only run on batteries for two hours and cost $3,000.

Cellphone manufacturers started offering built-in GPS in the late 1990s. In 2002, the Federal Communications Commission mandated the system be built into cell towers to triangulate a user calling 911.

The U.S. military relies on built-in GPS to guide weapons to its targets. But the civilian benefits of this technology range from mapping to disaster relief. And, of course, self-driving cars.

Another popular commercial application of GPS is “fleet management.” Companies can monitor their employees’ movement with GPS-equipped vehicles.

Law enforcement also uses GPS. A commercial device called Stingray can ping any phone to determine its location. According to the American Civil Liberties Union, 75 law enforcement agencies in 27 states use Stingray. But in Connecticut, they first need a warrant.

Some countries, including Russia, members of the European Union, India and Japan, have their own GPS systems. Adding the Russian GLONASS system to our GPS can increase its accuracy to 2 meters. A separate Chinese GPS system, Beidou, will be operational globally by 2020.

But all of this tech is not foolproof. Homeland Security worries about GPS spoofing and jamming. Though prohibited by law, a $33 GPS jamming device has been used to interfere with location tracking at such sensitive locations as U.S. airports.

In an era when killer satellites can blast a GPS bird in outer space, some are concerned about our vulnerability during a war when zapping just four U.S. GPS satellites could cripple our system.

So as you head to grandma’s house for the holidays, you might just want to keep an old-school paper map in your glove compartment.

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