Slashdot has reported a Business Week story By Otis Port — “Any technology can be a two-edged sword. Cell phones are a good example. They’re clearly a great convenience, even a life-saving tool during natural disasters and medical emergencies. And they should save many more lives under the Federal Communications Commission’s enhanced 911 mandate, which requires that cell phones relay their precise locations to 911 operators.
Yet some people are appalled that their cell phone will always give away where they are. That makes it possible to compile a “road map” of a user’s movements. So imagine the outcry when privacy worriers learn that cell-phone systems can be used to locate and track a car, boat, or plane — even if no one inside is carrying a wireless phone. But outcry or not, the technology seems certain to be deployed, given its myriad civilian and military applications.
The technology is called Celldar, from “cellular” plus “radar.” Under development since 1997 at Roke Manor Research Ltd (SI ). in Romsey, England, it differs from conventional radar in several key respects. When radar tracks planes for air traffic controllers — or maps the surface of Venus from a space probe — the same set of equipment both sends out radio signals and picks up the returning echoes. So computers can easily calculate an object’s distance and relative size based on how long it takes the returning signals to bounce back and how strong they are.”
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