Sorry, Paul Simon, but this BusinessWeek article shows the process of elimination shopkick’s CTO went through to narrow down smartphone components which could help distinguish whether users of his app are inside an American Eagle Outfitter or the Old Navy down the block - “cellular radio, GPS, Wi-Fi, Bluetooth, accelerometer, magnetometer, camera, microphone.”
“The breakthrough—that inaudible messages could be pumped through speakers at a store and picked up by a phone—brought its own challenges. Modems transmitted over a phone line and never had to account for much echo. Sound waves change as they bounce off walls and displays in a store before reaching a phone. Emigh and his team eventually found ways to deal with echo and the various characteristics of each phone’s mic. But the technology worked only if a shopper stood still near the store’s entryway. “The one that we hadn’t thought about was Doppler shift,” he says, referring to how sound changes as subjects move. To overcome this hurdle, the team wrote an algorithm to compensate for movement.”
Photo Credit shopkick
This would be a good article if it were edited. Good insights.
Posted by: guild wars 2 gold sell | February 16, 2013 at 12:54 AM