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Surprisingly, the system isn’t entirely wireless.
At this weekend’s Bank of America Chicago Marathon, approximately 45,000 runners–from world-class Kenyans to recreational enthusiasts–will affix a little computer chip to their shoes.
How exactly do these things work?
According to an article posted on the Chicago Sun Times’ Web site, the particular chip this year is called a “D-Tag”–short for RFID tag. It’s produced by a company from Evansville, Illinois, ChronoTrack Systems.
Race organizers have been using these tags since 1998. Technological advances have made the accessability of information even quicker. Last year, the marathon changed tag suppliers, which will improve the accuracy and availability even more.
The race timing system takes into account how long it takes for a runner to reach the start line.
“A person’s race does not begin until he or she hits the start line,” said Paul Farmer, director of information technology at Chicago Event Management Inc., which runs the marathon. “Before timing technology, no one knew actual start times for runners in large races.”
Contrary to popular belief, the system isn’t entirely wireless. Wireless communication isn’t 100% reliable and so officials use high-speed wire at the start, finish, and checkpoints along the way.
For More: Chicago Sun Times