Sabtu, 25 September 2010

What Is "Super Wi-Fi"? [Super Wi-fi]

The FCC just cleared a path for a new generation of "Super Wi-Fi" technologies. Sounds great! But what the heck is Super Wi-Fi?

super wifi, wi-fiIt's not as though Super Wi-Fi is some entirely alien concept. For all intents and purposes, it's Wi-Fi! The same kind of wireless data transmission you use around your apartment or at the office or waiting in line at Starbucks. It's just much, much more powerful.

As John explained previously, pretty much all Wi-Fi activity takes place on the same 2.4GHz or 5GHz frequencies. For the first time in 25 years, though, the FCC has opened up a sizable new block of unlicensed spectrum, this time between 50MHz and 700MHz.

Ever since television went entirely digital, folks like Google have been lobbying, literally, to free up the airwaves between channels. The so-called "white spaces" would otherwise have been lying around unused or been subject to prohibitive regulatory precautions.

Unlike current Wi-Fi airwaves, whose reach can be measured in feet, the spectrum that would carry Super Wi-Fi would be able to travel for several miles because of that lower frequency. Through brick walls, even—something your Linksys really struggles with. You can also anticipate download speeds of 15Mbps to 20Mbps—about as fast as a cable modem.

Back in 2008, when the white space plan was first approved, the biggest concern was that using these airwaves for data transmission could interfere with TV signals. To mitigate those fears, white space devices will be required to query a special geolocation database, ensuring no signals are crossed.

The advantages are already apparent. Google, for instance, already has a trial running in a Logan, Ohio hospital that's giving first responders and the hospital grounds alike super-speedy broadband. Wilmington, NC uses white-space to send real-time feeds from traffic and security cameras. And eventually, you would potentially be able to access your home Wi-Fi from several blocks away.

So far, most of what we know about how the white space will be used is based on conjecture. There may be some proof-of-concept devices early next year at CES, and there may be more mass production of products in a year or two. But the first Super Wi-Fi projects are likely to be medical, municipal, large-scale. How long it takes for us to be always connected from anywhere and anything? That's up to the inventors and entrepreneurs to decide. [FCC (pdf)]

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