optical wireless
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Chinese scientists demonstrate 2Mbps internet connection over LED
LED data transmission used to be all the rage -- we fondly remember beaming Palm Pilot contacts via IrDA. Then we got omni-directional Bluetooth and building-penetrating WiFi, and put all that caveman stuff behind us. But now, scientists the world over are looking to bring back line-of-sight networking, and the latest demonstration has Chinese researchers streaming video to a laptop with naught but ceiling-mounted blue LEDs. The Chinese Academy of Sciences claims to have realized a 2Mbit per second internet connection that transmits data simply by modulating the flicker of the little diodes, and imperceptibly enough to have them serve as room lighting as well. Like Boston University before them, the Chinese scholars see short-range LED networks controlling smart appliances. It's not quite the gigabit speed you'd get from laser diodes, but this way you'll get more mileage out of those expensive new bulbs, eh?
Another optical wireless experiment shows us that LEDs will beam your future downloads
Beaming data with light is hardly a new thing, but lately we've seen a number of attempts at making it rather more usable and, more interesting, rather more speedy. We're starting to get the feeling that those maybe/maybe not dangerous microwave-based systems have had their days numbered. The latest to beam bits with blinkenlights is a team at the Fraunhofer Institute for Telecommunications in Germany, which will be showing its stuff at the always happenin' Optical Fiber Communication Conference and Exposition in two weeks. The team was able to use a commercial LED and get an impressive 230Mb/s transfer rate, which doesn't compare to the gigabit Penn State managed or 500mb/s Siemens pulled off, but those were done using rather more specialized hardware (like the Siemens rig pictured above). It's interesting stuff, and we're looking forward to see the commercial applications for this tech, but we do have one nagging question: what if you want to surf in the dark?
Penn State's optical wireless tech does gigabit, bounces off walls
We love our WiFi, but it's far from perfect. Speed depends greatly on conditions, magnetic waves don't always play nicely with sensitive equipment, and the ability for someone to drive by and steal your precious infos is always disconcerting. Researchers at Penn State have what they believe is a better solution: light. The team uses laser diodes to convert data signals to light, then photo diodes on the other end to convert it back to data, a system that (unlike others we've seen) doesn't require direct line of sight as the light will bounce off of walls -- except those painted black (sorry goths). Data access could easily be constrained within a single room or, if it was needed elsewhere, wired relays could bring it through walls. Speeds at this point are already at the 1Gb/sec range, twice what Siemens was able to manage a few weeks ago, and enough for wireless transmission of high-definition video. Someday your Wiimote and remote might not be the only things beaming back at ya in the living room.
